Archives

2025 ⁷¹⁰

August ⁵⁶

Find Largest Subset of Compatible Jobs (Interval Scheduling)

August 11, 2025 · 3 min · daily-coding-problem ·

Find Largest Consecutive Integer Range in Array

August 11, 2025 · 4 min · daily-coding-problem ·

Optimal Array Rounding with Sum Preservation

August 10, 2025 · 19 min · daily-coding-problem ·

Distributed Wikipedia Crawler System Design

August 10, 2025 · 30 min · daily-coding-problem ·

Crossword Grid Validation

August 10, 2025 · 23 min · daily-coding-problem ·

Word Sense Disambiguation Algorithm

August 10, 2025 · 19 min · daily-coding-problem ·

Soundex Algorithm Implementation

August 10, 2025 · 15 min · daily-coding-problem ·

Ternary Search Tree Implementation

August 10, 2025 · 14 min · daily-coding-problem ·

Lexicographically Smallest String with K-Position Moves

August 10, 2025 · 13 min · daily-coding-problem · Last updated: Aug 10, 2025

Maximum Edge Removal for Even Subtrees

August 10, 2025 · 11 min · daily-coding-problem ·

Maximum Word Packing on Board

August 10, 2025 · 18 min · daily-coding-problem ·

Closest pair of points

August 10, 2025 · 16 min · daily-coding-problem · coordinate-geometry · point · pair_tuple · divide-n-conquer · Last updated: Aug 11, 2025

Next Bigger Integer with Same Number of 1-Bits

August 10, 2025 · 13 min · daily-coding-problem · Last updated: Aug 10, 2025

Uniformly Shuffle Linked List Nodes

August 10, 2025 · 13 min · daily-coding-problem ·

Ways To Form Max Heap

August 10, 2025 · 6 min · heap · interviewbit · daily-coding-problem · Last updated: Aug 16, 2025

PageRank Algorithm Implementation

August 10, 2025 · 16 min · daily-coding-problem ·

Count Pairs with Given Sum and XOR

August 10, 2025 · 14 min · daily-coding-problem ·

Minimum Flips to Separate X and Y

August 10, 2025 · 11 min · daily-coding-problem ·

2-CNF Boolean Satisfiability Problem

August 10, 2025 · 16 min · daily-coding-problem ·

Stable Marriage Problem

August 10, 2025 · 14 min · daily-coding-problem ·

Implement Elo Rating System

August 10, 2025 · 16 min · daily-coding-problem ·

Construct Cartesian Tree from Sequence

August 10, 2025 · 12 min · daily-coding-problem ·

Minimize Maximum Mouse Distance to Holes

August 10, 2025 · 8 min · daily-coding-problem ·

Approximate Median in Sub-linear Time

August 10, 2025 · 12 min · daily-coding-problem · Last updated: Aug 10, 2025

8-Puzzle Solver

August 10, 2025 · 16 min · daily-coding-problem ·

Find Coin Denominations from Change Count

August 10, 2025 · 10 min · daily-coding-problem ·

Minimum Radio Tower Broadcast Range

August 10, 2025 · 7 min · daily-coding-problem ·

Find Peak in Rotated Sorted Array

August 10, 2025 · 7 min · daily-coding-problem · Last updated: Aug 10, 2025

Minimize Cost to Remove Gaps Between People

August 10, 2025 · 10 min · daily-coding-problem ·

BST Floor and Ceiling

August 10, 2025 · 9 min · daily-coding-problem ·

Bloom Filter Implementation

August 10, 2025 · 12 min · daily-coding-problem ·

Election Voting Machine Monitor

August 10, 2025 · 11 min · daily-coding-problem ·

Water Plant Infrastructure Optimization

August 9, 2025 · 11 min · daily-coding-problem ·

Bartender Drink Optimization

August 9, 2025 · 12 min · daily-coding-problem ·

Stone Pyramid Construction

August 9, 2025 · 12 min · daily-coding-problem · Last updated: Aug 9, 2025

Dodgeball Team Division

August 9, 2025 · 14 min · daily-coding-problem ·

Qux Color Transformation

August 9, 2025 · 11 min · daily-coding-problem ·

Kaprekar’s Constant Calculator

August 9, 2025 · 11 min · daily-coding-problem ·

Website Similarity Analysis

August 9, 2025 · 14 min · daily-coding-problem ·

Pythagorean Triplet Detection

August 9, 2025 · 9 min · daily-coding-problem ·

Binary Search Without Multiplication, Division and Bit-shift Operations

August 9, 2025 · 10 min · daily-coding-problem · binary-search · array · search · constraints · Last updated: Aug 9, 2025

Chess King Check Detector

August 8, 2025 · 17 min · daily-coding-problem · chess · matrix · game-theory · simulation ·

Step Word Anagram Generator

August 8, 2025 · 11 min · daily-coding-problem · string-processing · anagrams · hash-map · sorting · Last updated: Aug 10, 2025

Sentence Validation Stream Processor

August 8, 2025 · 13 min · daily-coding-problem · string-processing · validation · stream-processing ·

Prune Unary nodes to form Full Binary Tree

August 7, 2025 · 19 min · binary-tree · tree-traversal · recursion · tree-transformation · Last updated: Aug 7, 2025

Egyptian Fraction

August 6, 2025 · 14 min · mathematical-algorithm · number-theory · fraction · euclidean-algorithm · greedy · Last updated: Aug 7, 2025

External Sorting of integers

August 6, 2025 · 23 min · daily-coding-problem · external-sorting · divide-and-conquer · merge-sort · memory-management · algorithms · Last updated: Aug 7, 2025

Three-Word Additive Cryptarithmetic Solver

August 6, 2025 · 25 min · daily-coding-problem · backtracking · constraint-satisfaction · mathematical-puzzle · permutation · Last updated: Aug 7, 2025

Check if words chain to form a circle

August 6, 2025 · 12 min · algorithms · daily-coding-problem · graph · dfs · backtracking · eulerian-path · Last updated: Aug 7, 2025

Maximum of Two Numbers Without Conditionals

August 6, 2025 · 8 min · algorithms · daily-coding-problem · bit-manipulation · math · no-conditionals · Last updated: Aug 6, 2025

Prime Generator

August 6, 2025 · 7 min · algorithms · daily-coding-problem · generator · iterator · prime-numbers · sieve · math · Last updated: Aug 6, 2025

Maximum Weight Spanning Tree

August 4, 2025 · 9 min · graph · mst-minimum-spanning-tree · daily-coding-problem · maximum-spanning-tree · Last updated: Aug 4, 2025

Minimum and Maximum in an array with Optimal Comparisons

August 4, 2025 · 9 min · array · divide-and-conquer · optimization · daily-coding-problem · Last updated: Aug 4, 2025

Point in Polygon

August 4, 2025 · 19 min · geometry · computational-geometry · ray-casting · daily-coding-problem · Last updated: Aug 4, 2025

Symmetric N-ary Tree Detection

August 4, 2025 · 8 min · tree · k-ary-tree · symmetry · recursion · daily-coding-problem · Last updated: Aug 4, 2025

Blackjack Optimal Strategy with Known Card Sequence

August 4, 2025 · 15 min · daily-coding-problem · game-theory · dynamic-programming · optimization · Last updated: Aug 10, 2025

July ¹⁴¹

Minimum Insertion OR Deletion Steps to Make a String Palindrome

July 24, 2025 · 8 min · string · palindrome · dynamic-programming · Last updated: Jul 25, 2025

Minimum Deletion Steps to Make a String Palindrome

July 24, 2025 · 7 min · longest · dynamic-programming · palindrome · Last updated: Jul 25, 2025

Closest Equal Element Queries

July 1, 2025 · 4 min · array · binary-search · hash-table · leetcode · Last updated: Aug 2, 2025

Check If Digits Are Equal in String After Operations I

July 1, 2025 · 4 min · combinatorics · leetcode · math · number-theory · simulation · string · Last updated: Jul 3, 2025

Check If Digits Are Equal in String After Operations II

July 1, 2025 · 6 min · combinatorics · leetcode · math · number-theory · string · Last updated: Jul 6, 2025

Choose K Elements With Maximum Sum

July 1, 2025 · 5 min · array · heap-priority-queue · leetcode · sorting · Last updated: Jul 4, 2025

Concatenated Divisibility

July 1, 2025 · 9 min · array · bit-manipulation · bitmask · dynamic-programming · leetcode · Last updated: Jul 26, 2025

Count Beautiful Numbers

July 1, 2025 · 9 min · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Count Beautiful Splits in an Array

July 1, 2025 · 5 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Count Cells in Overlapping Horizontal and Vertical Substrings

July 1, 2025 · 4 min · array · hash-function · leetcode · matrix · rolling-hash · string · string-matching · Last updated: Aug 2, 2025

Count Connected Components in LCM Graph

July 1, 2025 · 7 min · array · hash-table · leetcode · math · number-theory · union-find · Last updated: Aug 2, 2025

Count Covered Buildings

July 1, 2025 · 4 min · array · hash-table · leetcode · sorting · Last updated: Aug 2, 2025

Count Mentions Per User

July 1, 2025 · 11 min · array · leetcode · math · simulation · sorting · Last updated: Aug 2, 2025

Count Non-Decreasing Subarrays After K Operations

July 1, 2025 · 17 min · array · leetcode · monotonic-queue · monotonic-stack · queue · segment-tree · sliding-window · stack · Last updated: Jul 26, 2025

Count Numbers with Non-Decreasing Digits

July 1, 2025 · 11 min · dynamic-programming · leetcode · math · string · Last updated: Aug 2, 2025

Count Partitions with Even Sum Difference

July 1, 2025 · 3 min · array · leetcode · math · prefix-sum · Last updated: Aug 2, 2025

Count Paths With the Given XOR Value

July 1, 2025 · 4 min · leetcode · Last updated: Aug 2, 2025

Count Special Subsequences

July 1, 2025 · 5 min · array · enumeration · hash-table · leetcode · math · Last updated: Aug 2, 2025

Count Substrings Divisible By Last Digit

July 1, 2025 · 5 min · dynamic-programming · leetcode · string · Last updated: Aug 2, 2025

Design Spreadsheet

July 1, 2025 · 5 min · array · design · hash-table · leetcode · matrix · string · Last updated: Jul 26, 2025

Design Task Manager

July 1, 2025 · 9 min · design · hash-table · heap-priority-queue · leetcode · ordered-set · Last updated: Aug 2, 2025

Digit Operations to Make Two Integers Equal

July 1, 2025 · 5 min · graph · heap-priority-queue · leetcode · math · number-theory · shortest-path · Last updated: Aug 2, 2025

DNA Pattern Recognition

July 1, 2025 · 5 min · database · leetcode · Last updated: Aug 2, 2025

Eat Pizzas!

July 1, 2025 · 5 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Equal Sum Grid Partition I

July 1, 2025 · 4 min · array · enumeration · leetcode · matrix · prefix-sum · Last updated: Aug 2, 2025

Equal Sum Grid Partition II

July 1, 2025 · 4 min · array · enumeration · hash-table · leetcode · matrix · prefix-sum · Last updated: Aug 2, 2025

Fill a Special Grid

July 1, 2025 · 7 min · array · divide-and-conquer · leetcode · matrix · Last updated: Jul 8, 2025

Find Closest Person

July 1, 2025 · 4 min · leetcode · math · Last updated: Aug 2, 2025

Find Followers Count

July 1, 2025 · 2 min · sql · database · leetcode · Last updated: Jul 23, 2025

Find Invalid IP Addresses

July 1, 2025 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Find Minimum Cost to Remove Array Elements

July 1, 2025 · 7 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Find Mirror Score of a String

July 1, 2025 · 6 min · hash-table · leetcode · simulation · stack · string · Last updated: Aug 2, 2025

Find Most Frequent Vowel and Consonant

July 1, 2025 · 5 min · counting · hash-table · leetcode · string · Last updated: Aug 2, 2025

Find Product Recommendation Pairs

July 1, 2025 · 5 min · database · leetcode · Last updated: Aug 2, 2025

Find Products with Three Consecutive Digits

July 1, 2025 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Find Products with Valid Serial Numbers

July 1, 2025 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Find Special Substring of Length K

July 1, 2025 · 5 min · leetcode · string · Last updated: Aug 2, 2025

Find Students Who Improved

July 1, 2025 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Find Sum of Array Product of Magical Sequences

July 1, 2025 · 10 min · array · bit-manipulation · bitmask · combinatorics · dynamic-programming · leetcode · math · Last updated: Aug 2, 2025

Find the Largest Almost Missing Integer

July 1, 2025 · 6 min · array · hash-table · leetcode · Last updated: Jul 26, 2025

Find the Lexicographically Largest String From the Box II

July 1, 2025 · 6 min · leetcode · string · two-pointers · Last updated: Aug 2, 2025

Find the Minimum Amount of Time to Brew Potions

July 1, 2025 · 7 min · array · leetcode · prefix-sum · simulation · Last updated: Jul 26, 2025

Find the Most Common Response

July 1, 2025 · 5 min · array · counting · hash-table · leetcode · string · Last updated: Aug 2, 2025

Find the Number of Copy Arrays

July 1, 2025 · 5 min · array · leetcode · math · Last updated: Aug 2, 2025

Find Valid Emails

July 1, 2025 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Find Valid Pair of Adjacent Digits in String

July 1, 2025 · 4 min · counting · hash-table · leetcode · string · Last updated: Aug 2, 2025

Find X Value of Array I

July 1, 2025 · 5 min · array · dynamic-programming · leetcode · math · Last updated: Aug 2, 2025

Find X Value of Array II

July 1, 2025 · 5 min · array · leetcode · math · segment-tree · Last updated: Aug 2, 2025

First Letter Capitalization II

July 1, 2025 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Frequencies of Shortest Supersequences

July 1, 2025 · 4 min · array · bit-manipulation · enumeration · graph · leetcode · string · topological-sort · Last updated: Aug 2, 2025

Fruits Into Baskets II

July 1, 2025 · 5 min · array · binary-search · leetcode · segment-tree · simulation · Last updated: Aug 2, 2025

Fruits Into Baskets III

July 1, 2025 · 11 min · array · binary-search · leetcode · ordered-set · segment-tree · Last updated: Aug 6, 2025

Implement Router

July 1, 2025 · 7 min · array · binary-search · design · hash-table · leetcode · ordered-set · queue · Last updated: Aug 2, 2025

Length of Longest V-Shaped Diagonal Segment

July 1, 2025 · 10 min · array · dynamic-programming · leetcode · matrix · memoization · Last updated: Aug 2, 2025

Lexicographically Smallest Generated String

July 1, 2025 · 8 min · greedy · leetcode · string · string-matching · Last updated: Aug 2, 2025

Longest Common Prefix of K Strings After Removal

July 1, 2025 · 16 min · array · leetcode · string · trie · Last updated: Aug 7, 2025

Longest Palindrome After Substring Concatenation I

July 1, 2025 · 8 min · dynamic-programming · enumeration · leetcode · string · two-pointers · Last updated: Aug 7, 2025

Longest Palindrome After Substring Concatenation II

July 1, 2025 · 20 min · dynamic-programming · leetcode · string · two-pointers · Last updated: Aug 7, 2025

Longest Palindromic Subsequence After at Most K Operations

July 1, 2025 · 12 min · dynamic-programming · leetcode · string · Last updated: Aug 7, 2025

Longest Special Path

July 1, 2025 · 8 min · array · depth-first-search · hash-table · leetcode · prefix-sum · tree · Last updated: Aug 2, 2025

Longest Special Path II

July 1, 2025 · 9 min · array · depth-first-search · hash-table · leetcode · prefix-sum · tree · Last updated: Aug 2, 2025

Longest Subsequence With Decreasing Adjacent Difference

July 1, 2025 · 5 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Make Array Non-decreasing

July 1, 2025 · 4 min · array · greedy · leetcode · monotonic-stack · stack · Last updated: Aug 2, 2025

Manhattan Distances of All Arrangements of Pieces

July 1, 2025 · 11 min · combinatorics · leetcode · math · Last updated: Aug 2, 2025

Maximize Active Section with Trade I

July 1, 2025 · 10 min · enumeration · leetcode · string · Last updated: Aug 2, 2025

Maximize Active Section with Trade II

July 1, 2025 · 6 min · array · binary-search · leetcode · segment-tree · string · Last updated: Aug 2, 2025

Maximize Amount After Two Days of Conversions

July 1, 2025 · 12 min · array · breadth-first-search · depth-first-search · graph · leetcode · string · Last updated: Aug 2, 2025

Maximize Subarray Sum After Removing All Occurrences of One Element

July 1, 2025 · 4 min · array · dynamic-programming · leetcode · segment-tree · Last updated: Aug 2, 2025

Maximize Subarrays After Removing One Conflicting Pair

July 1, 2025 · 6 min · array · enumeration · leetcode · prefix-sum · segment-tree · Last updated: Jul 26, 2025

Maximize the Distance Between Points on a Square

July 1, 2025 · 9 min · array · binary-search · greedy · leetcode · Last updated: Aug 2, 2025

Maximize the Minimum Game Score

July 1, 2025 · 6 min · array · binary-search · greedy · leetcode · Last updated: Aug 2, 2025

Maximum Amount of Money Robot Can Earn

July 1, 2025 · 8 min · array · dynamic-programming · leetcode · matrix · Last updated: Aug 2, 2025

Maximum and Minimum Sums of at Most Size K Subarrays

July 1, 2025 · 6 min · array · leetcode · math · monotonic-stack · stack · Last updated: Aug 2, 2025

Maximum and Minimum Sums of at Most Size K Subsequences

July 1, 2025 · 6 min · array · combinatorics · dynamic-programming · leetcode · math · sorting · Last updated: Aug 2, 2025

Maximum Area Rectangle With Point Constraints I

July 1, 2025 · 8 min · array · binary-indexed-tree · enumeration · geometry · leetcode · math · segment-tree · sorting · Last updated: Aug 2, 2025

Maximum Area Rectangle With Point Constraints II

July 1, 2025 · 9 min · array · binary-indexed-tree · geometry · leetcode · math · segment-tree · sorting · Last updated: Aug 2, 2025

Maximum Coins From K Consecutive Bags

July 1, 2025 · 6 min · array · binary-search · greedy · leetcode · prefix-sum · sliding-window · sorting · Last updated: Aug 2, 2025

Maximum Containers on a Ship

July 1, 2025 · 3 min · leetcode · math · Last updated: Aug 2, 2025

Maximum Frequency After Subarray Operation

July 1, 2025 · 4 min · array · dynamic-programming · enumeration · greedy · hash-table · leetcode · prefix-sum · Last updated: Aug 2, 2025

Maximum Number of Distinct Elements After Operations

July 1, 2025 · 4 min · leetcode · Last updated: Aug 2, 2025

Maximum Product of Subsequences With an Alternating Sum Equal to K

July 1, 2025 · 9 min · array · dynamic-programming · hash-table · leetcode · Last updated: Aug 2, 2025

Maximum Product of Two Digits

July 1, 2025 · 5 min · leetcode · math · sorting · Last updated: Aug 2, 2025

Maximum Profit from Valid Topological Order in DAG

July 1, 2025 · 7 min · array · bit-manipulation · bitmask · dynamic-programming · graph · leetcode · topological-sort · Last updated: Aug 2, 2025

Maximum Score of Non-overlapping Intervals

July 1, 2025 · 14 min · array · binary-search · dynamic-programming · leetcode · sorting · Last updated: Aug 8, 2025

Maximum Subarray Sum With Length Divisible by K

July 1, 2025 · 5 min · array · hash-table · leetcode · prefix-sum · Last updated: Aug 2, 2025

Maximum Subarray With Equal Products

July 1, 2025 · 6 min · array · enumeration · leetcode · math · number-theory · sliding-window · Last updated: Aug 2, 2025

Maximum Sum of Edge Values in a Graph

July 1, 2025 · 6 min · depth-first-search · graph · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Maximum Sum With at Most K Elements

July 1, 2025 · 4 min · array · greedy · heap-priority-queue · leetcode · matrix · sorting · Last updated: Aug 2, 2025

Maximum Unique Subarray Sum After Deletion

July 1, 2025 · 7 min · array · greedy · hash-table · leetcode · Last updated: Jul 25, 2025

Maximum Weighted K-Edge Path

July 1, 2025 · 9 min · dynamic-programming · graph · hash-table · leetcode · Last updated: Aug 2, 2025

Merge Operations for Minimum Travel Time

July 1, 2025 · 8 min · array · dynamic-programming · leetcode · prefix-sum · Last updated: Aug 2, 2025

Minimize the Maximum Edge Weight of Graph

July 1, 2025 · 9 min · binary-search · breadth-first-search · depth-first-search · graph · leetcode · shortest-path · Last updated: Aug 2, 2025

Minimum Cost Good Caption

July 1, 2025 · 7 min · dynamic-programming · leetcode · string · Last updated: Aug 2, 2025

Minimum Cost to Divide Array Into Subarrays

July 1, 2025 · 7 min · array · dynamic-programming · leetcode · prefix-sum · Last updated: Aug 2, 2025

Minimum Cost to Make Arrays Identical

July 1, 2025 · 4 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Minimum Cost to Reach Every Position

July 1, 2025 · 5 min · array · leetcode · Last updated: Jul 26, 2025

Minimum Deletions for At Most K Distinct Characters

July 1, 2025 · 4 min · counting · greedy · hash-table · leetcode · sorting · string · Last updated: Aug 2, 2025

Minimum Increments for Target Multiples in an Array

July 1, 2025 · 5 min · array · bit-manipulation · bitmask · dynamic-programming · leetcode · math · number-theory · Last updated: Aug 2, 2025

Minimum Operations to Convert All Elements to Zero

July 1, 2025 · 6 min · array · greedy · hash-table · leetcode · monotonic-stack · stack · Last updated: Aug 2, 2025

Minimum Operations to Make Array Elements Zero

July 1, 2025 · 6 min · array · bit-manipulation · leetcode · math · Last updated: Aug 2, 2025

Minimum Operations to Make Array Sum Divisible by K

July 1, 2025 · 5 min · array · leetcode · math · Last updated: Aug 2, 2025

Minimum Operations to Make Character Frequencies Equal

July 1, 2025 · 6 min · counting · dynamic-programming · enumeration · hash-table · leetcode · string · Last updated: Aug 2, 2025

Minimum Operations to Make Columns Strictly Increasing

July 1, 2025 · 4 min · array · greedy · leetcode · matrix · Last updated: Aug 2, 2025

Minimum Operations to Make Elements Within K Subarrays Equal

July 1, 2025 · 7 min · array · dynamic-programming · hash-table · heap-priority-queue · leetcode · math · sliding-window · Last updated: Aug 2, 2025

Minimum Pair Removal to Sort Array I

July 1, 2025 · 5 min · array · doubly-linked-list · hash-table · heap-priority-queue · leetcode · linked-list · ordered-set · simulation · Last updated: Aug 2, 2025

Minimum Pair Removal to Sort Array II

July 1, 2025 · 5 min · array · doubly-linked-list · hash-table · heap-priority-queue · leetcode · linked-list · ordered-set · simulation · Last updated: Jul 26, 2025

Minimum Time to Break Locks I

July 1, 2025 · 7 min · array · backtracking · bit-manipulation · bitmask · dynamic-programming · leetcode · Last updated: Jul 23, 2025

Number of Unique XOR Triplets I

July 1, 2025 · 5 min · array · bit-manipulation · leetcode · math · Last updated: Aug 2, 2025

Number of Unique XOR Triplets II

July 1, 2025 · 4 min · array · bit-manipulation · enumeration · leetcode · math · Last updated: Aug 2, 2025

Paint House IV

July 1, 2025 · 8 min · array · dynamic-programming · leetcode · Last updated: Jul 26, 2025

Path Existence Queries in a Graph I

July 1, 2025 · 6 min · array · binary-search · graph · hash-table · leetcode · union-find · Last updated: Aug 2, 2025

Path Existence Queries in a Graph II

July 1, 2025 · 9 min · array · binary-search · graph · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Permutations IV

July 1, 2025 · 12 min · array · combinatorics · enumeration · leetcode · math · Last updated: Aug 2, 2025

Properties Graph

July 1, 2025 · 7 min · array · breadth-first-search · depth-first-search · graph · hash-table · leetcode · union-find · Last updated: Aug 2, 2025

Reschedule Meetings for Maximum Free Time I

July 1, 2025 · 6 min · array · greedy · leetcode · sliding-window · Last updated: Aug 2, 2025

Reschedule Meetings for Maximum Free Time II

July 1, 2025 · 14 min · array · enumeration · greedy · leetcode · Last updated: Jul 10, 2025

Reverse Degree of a String

July 1, 2025 · 3 min · leetcode · simulation · string · Last updated: Aug 2, 2025

Select K Disjoint Special Substrings

July 1, 2025 · 7 min · dynamic-programming · greedy · hash-table · leetcode · sorting · string · Last updated: Aug 2, 2025

Separate Squares I

July 1, 2025 · 4 min · array · binary-search · leetcode · Last updated: Aug 2, 2025

Separate Squares II

July 1, 2025 · 6 min · array · binary-search · leetcode · line-sweep · segment-tree · Last updated: Aug 2, 2025

Shortest Matching Substring

July 1, 2025 · 4 min · binary-search · leetcode · string · string-matching · two-pointers · Last updated: Aug 2, 2025

Shortest Path in a Weighted Tree

July 1, 2025 · 7 min · array · binary-indexed-tree · depth-first-search · leetcode · segment-tree · tree · Last updated: Aug 2, 2025

Smallest Index With Digit Sum Equal to Index

July 1, 2025 · 2 min · array · leetcode · math · Last updated: Aug 2, 2025

Smallest Number With All Set Bits

July 1, 2025 · 2 min · bit-manipulation · leetcode · math · Last updated: Aug 2, 2025

Smallest Palindromic Rearrangement I

July 1, 2025 · 3 min · counting-sort · leetcode · sorting · string · Last updated: Aug 2, 2025

Smallest Palindromic Rearrangement II

July 1, 2025 · 1 min · combinatorics · counting · hash-table · leetcode · math · string · Last updated: Aug 2, 2025

Smallest Substring With Identical Characters I

July 1, 2025 · 9 min · leetcode · Last updated: Jul 27, 2025

Smallest Substring With Identical Characters II

July 1, 2025 · 7 min · leetcode · Last updated: Aug 2, 2025

Stock Price Fluctuation

July 1, 2025 · 6 min · data-stream · design · hash-table · heap-priority-queue · leetcode · ordered-set · Last updated: Aug 11, 2025

Subsequences with a Unique Middle Mode I

July 1, 2025 · 7 min · leetcode · Last updated: Aug 2, 2025

Substring Matching Pattern

July 1, 2025 · 5 min · leetcode · string · string-matching · Last updated: Aug 2, 2025

Subtree Inversion Sum

July 1, 2025 · 6 min · array · depth-first-search · dynamic-programming · leetcode · tree · Last updated: Jul 26, 2025

Sum of Good Numbers

July 1, 2025 · 4 min · array · leetcode · Last updated: Jul 26, 2025

Sum of K Subarrays With Length at Least M

July 1, 2025 · 5 min · array · dynamic-programming · leetcode · prefix-sum · Last updated: Jul 26, 2025

Sum of Variable Length Subarrays

July 1, 2025 · 4 min · array · leetcode · prefix-sum · Last updated: Aug 2, 2025

Transform Array by Parity

July 1, 2025 · 3 min · array · counting · leetcode · sorting · Last updated: Aug 2, 2025

Transformed Array

July 1, 2025 · 4 min · array · leetcode · simulation · Last updated: Aug 2, 2025

Unique 3-Digit Even Numbers

July 1, 2025 · 3 min · array · enumeration · hash-table · leetcode · recursion · Last updated: Aug 2, 2025

Unit Conversion I

July 1, 2025 · 4 min · breadth-first-search · depth-first-search · graph · leetcode · Last updated: Aug 2, 2025

Zero Array Transformation IV

July 1, 2025 · 7 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Zigzag Grid Traversal With Skip

July 1, 2025 · 5 min · array · leetcode · matrix · simulation · Last updated: Aug 2, 2025

June ⁷¹

Design a 3D Binary Matrix with Efficient Layer Tracking

June 30, 2025 · 3 min · leetcode · Last updated: Aug 2, 2025

Design an Array Statistics Tracker

June 30, 2025 · 4 min · binary-search · data-stream · design · hash-table · heap-priority-queue · leetcode · ordered-set · queue · Last updated: Aug 2, 2025

Find Circular Gift Exchange Chains

June 30, 2025 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Longest Common Prefix After at Most One Removal

June 30, 2025 · 4 min · leetcode · string · two-pointers · Last updated: Aug 2, 2025

Longest Team Pass Streak

June 30, 2025 · 2 min · database · leetcode · Last updated: Aug 2, 2025

Make a Positive Array

June 30, 2025 · 2 min · array · greedy · leetcode · prefix-sum · Last updated: Aug 2, 2025

Maximize Profit from Task Assignment

June 30, 2025 · 2 min · array · greedy · heap-priority-queue · leetcode · sorting · Last updated: Aug 2, 2025

Maximize Score After Pair Deletions

June 30, 2025 · 2 min · array · greedy · leetcode · Last updated: Aug 2, 2025

Maximum Coin Collection

June 30, 2025 · 2 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Maximum Students on a Single Bench

June 30, 2025 · 2 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

Minimum Operations to Make Subarray Elements Equal

June 30, 2025 · 9 min · array · hash-table · heap-priority-queue · leetcode · math · sliding-window · Last updated: Jul 26, 2025

Minimum Runes to Add to Cast Spell

June 30, 2025 · 10 min · array · breadth-first-search · depth-first-search · graph · leetcode · topological-sort · Last updated: Jul 26, 2025

Minimum Threshold for Inversion Pairs Count

June 30, 2025 · 5 min · array · binary-indexed-tree · binary-search · leetcode · segment-tree · Last updated: Aug 2, 2025

Minimum Time to Break Locks II

June 30, 2025 · 4 min · array · depth-first-search · graph · leetcode · Last updated: Jul 23, 2025

Minimum Time to Visit All Houses

June 30, 2025 · 4 min · array · leetcode · prefix-sum · Last updated: Aug 2, 2025

Minimum Unlocked Indices to Sort Nums

June 30, 2025 · 6 min · array · hash-table · leetcode · Last updated: Jul 26, 2025

Multiply Two Polynomials

June 30, 2025 · 2 min · array · leetcode · math · Last updated: Aug 2, 2025

Permutations III

June 30, 2025 · 4 min · array · backtracking · leetcode · Last updated: Aug 2, 2025

Phone Number Prefix

June 30, 2025 · 3 min · array · leetcode · sorting · string · trie · Last updated: Jul 26, 2025

Range XOR Queries with Subarray Reversals

June 30, 2025 · 11 min · array · binary-tree · leetcode · tree · Last updated: Jul 15, 2025

Subsequences with a Unique Middle Mode II

June 30, 2025 · 5 min · array · combinatorics · hash-table · leetcode · math · Last updated: Aug 2, 2025

Team Dominance by Pass Success

June 30, 2025 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Unit Conversion II

June 30, 2025 · 7 min · array · breadth-first-search · depth-first-search · graph · leetcode · math · Last updated: Aug 2, 2025

Calculate Score After Performing Instructions

June 30, 2025 · 5 min · array · hash-table · leetcode · simulation · string · Last updated: Jul 1, 2025

Find Time Required to Eliminate Bacterial Strains

June 30, 2025 · 5 min · array · greedy · heap-priority-queue · leetcode · math · Last updated: Aug 2, 2025

Find Subsequence of Length K With the Largest Sum

June 28, 2025 · 4 min · array · hash-table · heap-priority-queue · leetcode · sorting · Last updated: Aug 2, 2025

Longest Subsequence Repeated k Times

June 27, 2025 · 9 min · backtracking · counting · enumeration · greedy · leetcode · string · Last updated: Aug 2, 2025

Kth Smallest Product of Two Sorted Arrays

June 25, 2025 · 9 min · array · binary-search · leetcode · Last updated: Aug 2, 2025

Sum of k-Mirror Numbers

June 23, 2025 · 7 min · enumeration · leetcode · math · Last updated: Jul 31, 2025

Divide a String Into Groups of Size k

June 22, 2025 · 5 min · leetcode · simulation · string · Last updated: Aug 2, 2025

Minimum Deletions to Make String K-Special

June 21, 2025 · 6 min · counting · greedy · hash-table · leetcode · sorting · string · Last updated: Jun 28, 2025

Maximum Manhattan Distance After K Changes

June 20, 2025 · 5 min · counting · hash-table · leetcode · math · string · Last updated: Jul 31, 2025

Partition Array Such That Maximum Difference Is K

June 19, 2025 · 4 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Divide Array Into Arrays With Max Difference

June 18, 2025 · 4 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Count the Number of Arrays with K Matching Adjacent Elements

June 17, 2025 · 8 min · combinatorics · leetcode · math · Last updated: Jul 31, 2025

Maximum Difference Between Increasing Elements

June 16, 2025 · 4 min · array · leetcode · Last updated: Aug 2, 2025

Max Difference You Can Get From Changing an Integer

June 15, 2025 · 7 min · greedy · leetcode · math · Last updated: Aug 2, 2025

Maximum Difference by Remapping a Digit

June 14, 2025 · 5 min · greedy · leetcode · math · Last updated: Aug 2, 2025

Maximum Difference Between Adjacent Elements in a Circular Array

June 12, 2025 · 3 min · array · leetcode · Last updated: Aug 2, 2025

Maximum Difference Between Even and Odd Frequency II

June 11, 2025 · 14 min · enumeration · leetcode · prefix-sum · sliding-window · string · Last updated: Jun 28, 2025

Maximum Difference Between Even and Odd Frequency I

June 10, 2025 · 5 min · counting · hash-table · leetcode · string · Last updated: Aug 2, 2025

Using a Robot to Print the Lexicographically Smallest String

June 6, 2025 · 6 min · greedy · hash-table · leetcode · stack · string · Last updated: Aug 2, 2025

Analyze Organization Hierarchy

June 4, 2025 · 6 min · database · leetcode · Last updated: Jul 3, 2025

Analyze Subscription Conversion

June 4, 2025 · 5 min · database · leetcode · Last updated: Aug 2, 2025

Apply Substitutions

June 4, 2025 · 4 min · array · breadth-first-search · depth-first-search · graph · hash-table · leetcode · string · topological-sort · Last updated: Aug 2, 2025

Assign Elements to Groups with Constraints

June 4, 2025 · 4 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

Find the Lexicographically Largest String From the Box I

June 4, 2025 · 5 min · enumeration · leetcode · string · two-pointers · Last updated: Aug 2, 2025

Angle Between Hands of a Clock

June 4, 2025 · 8 min · leetcode · math · Last updated: Aug 10, 2025

Ant on the Boundary

June 3, 2025 · 4 min · array · leetcode · prefix-sum · simulation · Last updated: Aug 2, 2025

Amount of Time for Binary Tree to Be Infected

June 3, 2025 · 7 min · binary-tree · breadth-first-search · depth-first-search · hash-table · leetcode · tree · Last updated: Aug 2, 2025

Ambiguous Coordinates

June 3, 2025 · 7 min · backtracking · enumeration · leetcode · string · Last updated: Aug 2, 2025

Distribute Candies Among Children III

June 3, 2025 · 4 min · combinatorics · leetcode · math · Last updated: Aug 2, 2025

Distribute Candies Among Children I

June 3, 2025 · 4 min · combinatorics · enumeration · leetcode · math · Last updated: Aug 2, 2025

Distribute Candies

June 3, 2025 · 3 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

Maximum Candies You Can Get from Boxes

June 3, 2025 · 6 min · array · breadth-first-search · graph · leetcode · Last updated: Aug 2, 2025

Alternating Groups 3

June 2, 2025 · 5 min · array · binary-indexed-tree · leetcode · Last updated: Aug 2, 2025

Alternating Groups 1

June 2, 2025 · 3 min · array · leetcode · sliding-window · Last updated: Aug 2, 2025

Alternating Digit Sum

June 2, 2025 · 3 min · leetcode · math · Last updated: Aug 1, 2025

Alphabet Board Path

June 1, 2025 · 4 min · hash-table · leetcode · string · Last updated: Aug 2, 2025

All Divisions With the Highest Score of a Binary Array

June 1, 2025 · 5 min · array · leetcode · Last updated: Aug 2, 2025

All Elements in Two Binary Search Trees

June 1, 2025 · 3 min · binary-search-tree · binary-tree · depth-first-search · leetcode · sorting · tree · Last updated: Aug 2, 2025

Alert Using Same Key-Card Three or More Times in a One Hour Period

June 1, 2025 · 4 min · array · hash-table · leetcode · sorting · string · Last updated: Aug 2, 2025

Advantage Shuffle

June 1, 2025 · 3 min · array · greedy · leetcode · sorting · two-pointers · Last updated: Aug 2, 2025

Adjacent Increasing Subarrays Detection II

June 1, 2025 · 5 min · array · binary-search · leetcode · Last updated: Aug 2, 2025

Adjacent Increasing Subarrays Detection I

June 1, 2025 · 4 min · array · leetcode · Last updated: Aug 2, 2025

Adding Two Negabinary Numbers

June 1, 2025 · 4 min · array · leetcode · math · Last updated: Jul 31, 2025

Add Minimum Number of Rungs

June 1, 2025 · 3 min · array · greedy · leetcode · Last updated: Aug 2, 2025

Add Edges to Make Degrees of All Nodes Even

June 1, 2025 · 7 min · graph · hash-table · leetcode · Last updated: Aug 2, 2025

Account Balance After Rounded Purchase

June 1, 2025 · 3 min · leetcode · math · Last updated: Jul 31, 2025

Abbreviating the Product of a Range

June 1, 2025 · 6 min · leetcode · math · Last updated: Jul 31, 2025

Distribute Candies Among Children II

June 1, 2025 · 4 min · combinatorics · enumeration · leetcode · math · Last updated: Aug 2, 2025

May ²⁷¹

1-bit and 2-bit Characters

May 30, 2025 · 2 min · array · leetcode · Last updated: Aug 2, 2025

24 Game

May 30, 2025 · 4 min · array · backtracking · leetcode · math · Last updated: Aug 2, 2025

4 Keys Keyboard

May 30, 2025 · 3 min · dynamic-programming · leetcode · math · Last updated: Aug 2, 2025

3Sum With Multiplicity

May 30, 2025 · 4 min · array · counting · hash-table · leetcode · sorting · two-pointers · Last updated: Aug 2, 2025

Maximize the Number of Target Nodes After Connecting Trees II

May 29, 2025 · 7 min · breadth-first-search · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Maximize the Number of Target Nodes After Connecting Trees I

May 28, 2025 · 6 min · breadth-first-search · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Divisible and Non-divisible Sums Difference

May 27, 2025 · 4 min · leetcode · math · Last updated: Jul 31, 2025

Largest Color Value in a Directed Graph

May 26, 2025 · 4 min · counting · dynamic-programming · graph · hash-table · leetcode · memoization · topological-sort · Last updated: Aug 2, 2025

Find Words Containing Character

May 24, 2025 · 2 min · array · leetcode · string · Last updated: Aug 2, 2025

Find the Maximum Sum of Node Values

May 23, 2025 · 10 min · array · bit-manipulation · dynamic-programming · greedy · leetcode · sorting · tree · Last updated: Aug 2, 2025

Print all unique substrings of a given string

May 21, 2025 · 7 min · Last updated: Aug 2, 2025

Print all substrings of a given string

May 21, 2025 · 3 min · Last updated: May 29, 2025

0-1 Knapsack Problem

May 21, 2025 · 16 min · dynamic-programming · Last updated: Aug 2, 2025

Airplane Seat Assignment Probability

May 21, 2025 · 2 min · array · brainteaser · dynamic-programming · leetcode · math · probability-and-statistics · sorting · two-pointers · Last updated: Aug 2, 2025

All Paths from Source to Target

May 21, 2025 · 4 min · backtracking · breadth-first-search · dag-directed-acyclic-graph · depth-first-search · graph · leetcode · Last updated: Aug 2, 2025

Array of Doubled Pairs

May 21, 2025 · 3 min · array · greedy · hash-table · leetcode · sorting · Last updated: Aug 2, 2025

Array With Elements Not Equal to Average of Neighbors

May 21, 2025 · 3 min · array · binary-search · breadth-first-search · depth-first-search · greedy · leetcode · math · matrix · recursion · sorting · union-find · Last updated: Jun 3, 2025

Assign Mice To Holes

May 21, 2025 · 2 min · greedy · Last updated: Aug 16, 2025

Best Position for a Service Centre

May 21, 2025 · 16 min · array · coordinate-geometry · depth-first-search · geometry · leetcode · math · randomized · tree · Last updated: Aug 1, 2025

Bomb Enemy

May 21, 2025 · 10 min · array · dynamic-programming · leetcode · matrix · Last updated: Aug 2, 2025

Breaking an integer into the sum of pairwise distinct positive integers

May 21, 2025 · 3 min · greedy · max-min · coursera · Last updated: Jun 9, 2025

Bulb Switcher

May 21, 2025 · 6 min · brainteaser · hash-table · leetcode · math · Last updated: Aug 1, 2025

Button with Longest Push Time

May 21, 2025 · 4 min · array · leetcode · Last updated: Aug 2, 2025

Can Make Palindrome from Substring

May 21, 2025 · 5 min · array · binary-search · bit-manipulation · database · dynamic-programming · greedy · hash-table · heap-priority-queue · leetcode · math · prefix-sum · sorting · string · todo · trie · Last updated: Aug 2, 2025

Car Pooling

May 21, 2025 · 8 min · array · heap-priority-queue · leetcode · prefix-sum · simulation · sorting · Last updated: Aug 2, 2025

Car Refuelling Algorithm

May 21, 2025 · 3 min · car-refuel · greedy · Last updated: Jun 4, 2025

Celebration Party

May 21, 2025 · 5 min · greedy · Last updated: Aug 2, 2025

Cellphone base covering

May 21, 2025 · 9 min · Last updated: Aug 2, 2025

Check If a String Contains All Binary Codes of Size K

May 21, 2025 · 6 min · bit-manipulation · bits · breadth-first-search · depth-first-search · graph · hash-function · hash-table · leetcode · rolling-hash · string · string/binary · topological-sort · Last updated: Aug 2, 2025

Check if a string contains an anagram of another string

May 21, 2025 · 3 min · string · string-algo · anagram · Last updated: Aug 2, 2025

Circus tower sorting

May 21, 2025 · 8 min · ctci · sorting · dynamic-programming · lcs-longest-common-sequence · Last updated: Aug 2, 2025

Climbing Stairs - At most m steps

May 21, 2025 · 9 min · Last updated: Aug 2, 2025

Coin Change - Count Number of Ways of representing Amount given Finite supply of denominations

May 21, 2025 · 11 min · recursion · dynamic-programming · coin · count · Last updated: Aug 2, 2025

Coin Change with Fewest Number of Coins Given Finite Supply

May 21, 2025 · 12 min · Last updated: Aug 2, 2025

Construct Quad Tree

May 21, 2025 · 12 min · array · divide-and-conquer · divide-n-conquer · leetcode · matrix · tree · tree/quad · Last updated: Jul 29, 2025

Construct Target Array With Multiple Sums

May 21, 2025 · 13 min · array · bit-manipulation · counting · database · design · hash-table · heap-priority-queue · leetcode · sliding-window · sorting · string · Last updated: Aug 2, 2025

Count All Valid Pickup and Delivery Options

May 21, 2025 · 3 min · combinatorics · dynamic-programming · leetcode · math · string · todo · Last updated: Aug 2, 2025

Count Different Palindromic Subsequences

May 21, 2025 · 12 min · dynamic-programming · leetcode · string · todo · Last updated: Aug 2, 2025

Count number of ways to fill an n x 4 grid using 1 x 4 tiles

May 21, 2025 · 3 min · dynamic-programming · count · Last updated: Aug 2, 2025

Count Numbers with Unique Digits

May 21, 2025 · 3 min · backtracking · dynamic-programming · leetcode · math · todo · Last updated: Aug 2, 2025

Count reverse pairs in two individually sorted parts of an array

May 21, 2025 · 7 min · array-algo · sorted-array · Last updated: Aug 2, 2025

Count Sorted Vowel Strings

May 21, 2025 · 11 min · combinatorics · count · dynamic-programming · leetcode · math · maths · Last updated: Aug 2, 2025

Count The Repetitions

May 21, 2025 · 7 min · dynamic-programming · leetcode · string · todo · Last updated: Aug 2, 2025

Count Vowels Permutation

May 21, 2025 · 5 min · array · counting · dynamic-programming · greedy · leetcode · matrix · simulation · string · Last updated: Aug 2, 2025

Critical Connections in a Network

May 21, 2025 · 9 min · array · biconnected-component · binary-search · breadth-first-search · concurrency · counting · database · depth-first-search · graph · greedy · hash-table · heap-priority-queue · leetcode · math · matrix · sorting · Last updated: Aug 8, 2025

Data Stream as Disjoint Intervals

May 21, 2025 · 6 min · binary-search · design · leetcode · ordered-set · todo · Last updated: Jul 31, 2025

Decode a string to all valid interpretations

May 21, 2025 · 4 min · backtracking · Last updated: Jun 12, 2025

Decrypt Word with cumulative ASCII shift

May 21, 2025 · 5 min · pramp · Last updated: Jul 24, 2025

Delete Columns to Make Sorted III

May 21, 2025 · 5 min · array · dynamic-programming · leetcode · string · Last updated: Aug 2, 2025

Design Snake Game

May 21, 2025 · 9 min · array · design · hash-table · leetcode · queue · simulation · todo · Last updated: Aug 2, 2025

Design Twitter (Data Structure Design)

May 21, 2025 · 7 min · design · design/data-structure · hash-table · heap-priority-queue · leetcode · linked-list · Last updated: Aug 2, 2025

Design Underground System

May 21, 2025 · 5 min · design · design/data-structure · hash-table · leetcode · string · Last updated: Aug 2, 2025

Detect Cycle in Directed Graph

May 21, 2025 · 10 min · graph/cycle · graph/directed · Last updated: Aug 9, 2025

Detect Cycle in Undirected Graph

May 21, 2025 · 13 min · daily-coding-problem · graph · depth-first-search · breadth-first-search · graph/undirected · union-find · Last updated: Aug 9, 2025

Detonate the Maximum Bombs

May 21, 2025 · 8 min · array · binary-search · breadth-first-search · data-stream · depth-first-search · design · dfs · geometry · graph · hash-table · heap-priority-queue · leetcode · math · monotonic-stack · ordered-set · prefix-sum · simulation · sliding-window · stack · string · two-pointers · Last updated: Aug 2, 2025

Dice Roll Simulation

May 21, 2025 · 12 min · array · concurrency · database · dynamic-programming · hash-table · leetcode · Last updated: Aug 2, 2025

Distinct Subsequences II

May 21, 2025 · 5 min · dynamic-programming · leetcode · string · todo · Last updated: Aug 2, 2025

Distribute Repeating Integers

May 21, 2025 · 7 min · array · backtracking · bit-manipulation · bitmask · data-stream · design · dynamic-programming · hash-table · leetcode · Last updated: Jul 31, 2025

Divide Chocolate

May 21, 2025 · 6 min · array · binary-search · leetcode · Last updated: Aug 2, 2025

Earliest Possible Day of Full Bloom

May 21, 2025 · 5 min · array · binary-search · breadth-first-search · counting · database · dynamic-programming · greedy · heap-priority-queue · leetcode · math · matrix · prefix-sum · simulation · sorting · string · Last updated: Aug 2, 2025

Find All Good Strings

May 21, 2025 · 9 min · database · dynamic-programming · hash-table · leetcode · math · string · string-matching · todo · Last updated: Aug 2, 2025

Find Critical and Pseudo-Critical Edges in Minimum Spanning Tree

May 21, 2025 · 10 min · array · breadth-first-search · depth-first-search · graph · hash-table · leetcode · math · minimum-spanning-tree · number-theory · sorting · strongly-connected-component · tree · union-find · Last updated: Aug 2, 2025

Find if there is a path between two vertices in a directed graph

May 21, 2025 · 9 min · breadth-first-search · ctci · depth-first-search · dfs · bfs · graph · directed-graph · Last updated: Aug 6, 2025

Find K Pairs with Smallest Sums

May 21, 2025 · 5 min · array · duplicates-algo · heap-priority-queue · leetcode · pair_tuple · Last updated: Jul 19, 2025

Find k Smallest Numbers from a million numbers

May 21, 2025 · 4 min · k-smallest-largest · selection · quickselect · heap · large-data-set · Last updated: Aug 15, 2025

Find largest 1M numbers in 1B numbers

May 21, 2025 · 14 min · ctci · todo · duplicates-algo · map-reduce · quicksort · partition · Last updated: Jul 23, 2025

Find Minimum Time to Finish All Jobs

May 21, 2025 · 6 min · array · backtracking · bit-manipulation · bitmask · breadth-first-search · counting · database · dynamic-programming · game-theory · graph · greedy · hash-table · leetcode · math · matrix · memoization · minimum-spanning-tree · sorting · topological-sort · union-find · Last updated: Aug 2, 2025

Find Original Array From Doubled Array

May 21, 2025 · 4 min · array · greedy · hash-table · hashing · leetcode · sorting · Last updated: Aug 2, 2025

Find the Kth Largest Integer in the Array

May 21, 2025 · 7 min · array · divide-and-conquer · heap-priority-queue · leetcode · quickselect · sorting · string · Last updated: Jul 20, 2025

Find the median in a row-wise sorted 2D matrix

May 21, 2025 · 7 min · array · matrix · array-algo · median · Last updated: Jul 19, 2025

Find the Nth Largest Element in a Rotated Sorted Array

May 21, 2025 · 6 min · search · rotate · rotated-array · rotated-sorted-array · Last updated: Aug 2, 2025

Find the Shortest Superstring

May 21, 2025 · 14 min · array · bit-manipulation · bitmask · dynamic-programming · leetcode · string · interviewbit · Last updated: Aug 18, 2025

Flatten 2D Vector

May 21, 2025 · 4 min · array · design · iterator · leetcode · todo · two-pointers · Last updated: Aug 2, 2025

Form Largest Integer With Digits That Add up to Target

May 21, 2025 · 6 min · array · database · dynamic-programming · geometry · hash-table · leetcode · math · sliding-window · sorting · string · string-matching · todo · two-pointers · Last updated: Aug 2, 2025

Fractional knapsack problem

May 21, 2025 · 8 min · greedy · Last updated: Aug 2, 2025

Freivald’s Algorithm for Matrix Product Verification

May 21, 2025 · 2 min · matrix · randomized · verification · named-algo-ds/algo · Last updated: Aug 15, 2025

Frog Jump

May 21, 2025 · 12 min · array · dynamic-programming · leetcode · todo · Last updated: Aug 2, 2025

Frog Jump II

May 21, 2025 · 4 min · array · binary-search · counting · greedy · hash-table · heap-priority-queue · incomplete · leetcode · matrix · search/binary · simulation · sorting · Last updated: Aug 2, 2025

Furthest Building You Can Reach

May 21, 2025 · 10 min · array · greedy · heap-priority-queue · leetcode · Last updated: Aug 2, 2025

Greatest Sum Divisible by Three

May 21, 2025 · 4 min · array · breadth-first-search · counting · database · depth-first-search · dynamic-programming · geometry · greedy · heap-priority-queue · leetcode · linked-list · math · matrix · recursion · sorting · stack · todo · two-pointers · union-find · Last updated: Aug 2, 2025

Guess Number Higher or Lower II

May 21, 2025 · 6 min · dynamic-programming · game-theory · leetcode · math · Last updated: Aug 2, 2025

Hotel Reviews

May 21, 2025 · 4 min · interviewbit · trie · string · sorting · Last updated: Aug 16, 2025

Identify the Largest Outlier in an Array

May 21, 2025 · 7 min · array · counting · enumeration · hash-table · leetcode · Last updated: Aug 2, 2025

Increasing Decreasing String

May 21, 2025 · 6 min · counting · hash-table · increasing · leetcode · string · todo · Last updated: Aug 2, 2025

Insert Delete Search and GetRandom in Constant Time 1 - Dupes not allowed

May 21, 2025 · 5 min · array · design · design/data-structure · hash-table · leetcode · math · randomized · Last updated: Aug 2, 2025

Insert Delete Search and GetRandom in Constant Time 2 - Duplicates allowed

May 21, 2025 · 5 min · array · design · design/data-structure · hash-table · leetcode · math · randomized · Last updated: Jul 27, 2025

Integer Break

May 21, 2025 · 8 min · dynamic-programming · integer · leetcode · math · maths · todo · Last updated: Aug 2, 2025

Integer Partition Algorithm

May 21, 2025 · 11 min · todo · recursion · dynamic-programming · partition · Last updated: Jun 17, 2025

Iterator for Combination

May 21, 2025 · 6 min · array · backtracking · combination · design · design/data-structure · iterator · leetcode · queue/priority · string · Last updated: Jul 29, 2025

Job Sequencing Problem

May 21, 2025 · 14 min · disjoint-set · greedy · Last updated: Aug 2, 2025

Jump Game 7

May 21, 2025 · 7 min · array · dynamic-programming · game-theory · leetcode · math · prefix-sum · sliding-window · string · Last updated: Aug 2, 2025

K-Concatenation Maximum Sum

May 21, 2025 · 6 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Karatsuba Fast Multiplication

May 21, 2025 · 8 min · divide-n-conquer · todo · numerical-algo · multiplication · Last updated: Aug 2, 2025

Karger’s algorithm for Minimum Cut

May 21, 2025 · 2 min · graph-cut · min-cut · graph · named-algo-ds/algo · Last updated: Aug 15, 2025

Kth Ancestor of a Tree Node

May 21, 2025 · 6 min · binary-search · breadth-first-search · depth-first-search · design · dynamic-programming · leetcode · tree · Last updated: Aug 2, 2025

Kth Smallest Instructions

May 21, 2025 · 6 min · array · combinatorics · dynamic-programming · leetcode · math · todo · yna · Last updated: Aug 2, 2025

Largest Multiple of Three

May 21, 2025 · 7 min · array · counting · database · dynamic-programming · greedy · hash-table · leetcode · sorting · string · Last updated: Aug 2, 2025

Largest Plus Sign

May 21, 2025 · 9 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Largest Sum of Averages

May 21, 2025 · 7 min · array · dynamic-programming · leetcode · prefix-sum · Last updated: Aug 2, 2025

Last Stone Weight II

May 21, 2025 · 5 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Least Operators to Express Number

May 21, 2025 · 7 min · dynamic-programming · leetcode · math · memoization · Last updated: Aug 1, 2025

Letter Case Permutation

May 21, 2025 · 7 min · backtracking · bfs · bit-manipulation · dfs · leetcode · string · Last updated: Aug 2, 2025

Lexicographically smallest prime pair with target sum

May 21, 2025 · 3 min · Last updated: Aug 18, 2025

License Key Formatting

May 21, 2025 · 4 min · leetcode · string · Last updated: Aug 2, 2025

Line Reflection

May 21, 2025 · 4 min · array · coordinate-geometry · hash-table · leetcode · math · Last updated: Aug 1, 2025

Logger Rate Limiter

May 21, 2025 · 3 min · data-stream · design · hash-table · leetcode · Last updated: Jul 27, 2025

Longest Arithmetic Subsequence of Given Difference

May 21, 2025 · 3 min · array · dynamic-programming · hash-table · leetcode · Last updated: Aug 2, 2025

Longest Bitonic Subsequence

May 21, 2025 · 8 min · dynamic-programming · longest · bitonic · subsequence · interviewbit · Last updated: Jul 22, 2025

Longest Chunked Palindrome Decomposition

May 21, 2025 · 5 min · dynamic-programming · greedy · hash-function · leetcode · rolling-hash · string · todo · two-pointers · Last updated: Jul 31, 2025

Longest Compound Word in an Array

May 21, 2025 · 4 min · ctci · word · string-algo · longest · Last updated: Aug 15, 2025

Longest Increasing Path in a Matrix

May 21, 2025 · 13 min · array · backtracking · breadth-first-search · depth-first-search · dfs · dynamic-programming · graph · leetcode · longest · matrix · memoization · path-finding · topological-sort · Last updated: Jul 23, 2025

Longest increasing subarray

May 21, 2025 · 7 min · longest · subarray · sliding-window · Last updated: Jul 25, 2025

Longest Increasing subarray with one change allowed

May 21, 2025 · 6 min · longest · subarray · Last updated: Aug 2, 2025

Longest Palindromic Subsequence - Get Subsequence

May 21, 2025 · 8 min · matrix · recursion · string-algo · dynamic-programming · longest · palindrome · subsequence · todo · Last updated: Jul 25, 2025

Longest Subarray having sum of elements atmost ‘k’

May 21, 2025 · 5 min · subarray · sliding-window · Last updated: Aug 16, 2025

Longest Subarray of Ones After Deleting One Element

May 21, 2025 · 8 min · array · bit-manipulation · bitmask · dynamic-programming · graph · leetcode · sliding-window · Last updated: Aug 1, 2025

Longest Subarray with Ones after Replacement

May 21, 2025 · 5 min · sliding-window · Last updated: Aug 2, 2025

Longest Turbulent Subarray

May 21, 2025 · 4 min · array · dynamic-programming · leetcode · sliding-window · Last updated: Aug 2, 2025

Longest ZigZag Path in a Binary Tree

May 21, 2025 · 5 min · binary-tree · bt-binary-tree · depth-first-search · dynamic-programming · leetcode · tree · Last updated: Aug 2, 2025

Longest Zigzag Subsequence

May 21, 2025 · 4 min · dynamic-programming · Last updated: Aug 15, 2025

Make Array Strictly Increasing

May 21, 2025 · 6 min · array · binary-search · dynamic-programming · leetcode · sorting · Last updated: Aug 2, 2025

Matchsticks to Square

May 21, 2025 · 11 min · array · backtracking · bit-manipulation · bitmask · dynamic-programming · leetcode · todo · Last updated: Aug 2, 2025

Matrix Chain Multiplication

May 21, 2025 · 9 min · todo · matrix · dynamic-programming · numerical-algo · multiplication · Last updated: Jun 20, 2025

Matrix Chain Multiplication 2 - Print brackets

May 21, 2025 · 4 min · matrix · dynamic-programming · numerical-algo · multiplication · Last updated: Aug 2, 2025

Max Dot Product of Two Subsequences

May 21, 2025 · 6 min · array · database · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Max Non-negative subarray sum

May 21, 2025 · 4 min · subarray · interviewbit · Last updated: Aug 16, 2025

Max Sum of Rectangle No Larger Than K

May 21, 2025 · 6 min · array · binary-search · leetcode · matrix · ordered-set · prefix-sum · sum · Last updated: Aug 2, 2025

Maximal Network Rank

May 21, 2025 · 6 min · graph · leetcode · Last updated: Aug 2, 2025

Maximize Grid Happiness

May 21, 2025 · 14 min · binary-tree · bit-manipulation · bitmask · breadth-first-search · database · depth-first-search · dynamic-programming · hash-table · leetcode · memoization · tree · Last updated: Aug 1, 2025

Maximize the Confusion of an Exam

May 21, 2025 · 10 min · array · binary-search · counting · enumeration · hash-table · leetcode · prefix-sum · sliding-window · string · Last updated: Aug 1, 2025

Maximizing Revenue in Online Ad Placement

May 21, 2025 · 4 min · greedy · max-min · coursera · Last updated: Jun 9, 2025

Maximum Alternating Subsequence Sum

May 21, 2025 · 16 min · array · design · dynamic-programming · hash-table · heap-priority-queue · leetcode · matrix · ordered-set · simulation · sorting · Last updated: Aug 2, 2025

Maximum Area of a Piece of Cake After Horizontal and Vertical Cuts

May 21, 2025 · 6 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Maximum Erasure Value

May 21, 2025 · 4 min · array · hash-table · leetcode · sliding-window · Last updated: Jul 22, 2025

Maximum Frequency Stack

May 21, 2025 · 5 min · design · design/data-structure · hash-table · leetcode · ordered-set · stack · Last updated: Aug 2, 2025

Maximum Length of Pair Chain

May 21, 2025 · 3 min · array · dynamic-programming · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Maximum Non Negative Product in a Matrix

May 21, 2025 · 8 min · array · dynamic-programming · leetcode · matrix · todo · Last updated: Aug 1, 2025

Maximum Number of Events That Can Be Attended II

May 21, 2025 · 6 min · array · binary-indexed-tree · binary-search · bit-manipulation · bitmask · design · dynamic-programming · greedy · hash-table · heap-priority-queue · leetcode · math · ordered-set · sorting · stack · string · two-pointers · Last updated: Aug 1, 2025

Maximum Number of Matching Indices After Right Shifts

May 21, 2025 · 4 min · array · backtracking · binary-indexed-tree · binary-search · binary-tree · bit-manipulation · bitmask · breadth-first-search · combinatorics · counting · counting-sort · database · depth-first-search · design · divide-and-conquer · doubly-linked-list · dynamic-programming · enumeration · graph · greedy · hash-function · hash-table · heap-priority-queue · leetcode · line-sweep · linked-list · math · matrix · memoization · monotonic-queue · monotonic-stack · number-theory · ordered-set · prefix-sum · queue · recursion · rolling-hash · segment-tree · shortest-path · simulation · sliding-window · sorting · stack · string · string-matching · topological-sort · tree · trie · two-pointers · union-find · Last updated: Aug 2, 2025

Maximum Product of Splitted Binary Tree

May 21, 2025 · 6 min · array · binary-tree · database · depth-first-search · dynamic-programming · leetcode · sorting · tree · Last updated: Aug 2, 2025

Maximum Product of Two Elements in an Array

May 21, 2025 · 4 min · array · heap-priority-queue · leetcode · numerical-algo · sorting · Last updated: Aug 2, 2025

Maximum revenue by selling K tickets from N windows

May 21, 2025 · 6 min · array · array-algo · window · Last updated: Jun 8, 2025

Maximum Score from Performing Multiplication

May 21, 2025 · 12 min · array · backtracking · breadth-first-search · counting · database · depth-first-search · dynamic-programming · graph · greedy · hash-table · heap-priority-queue · interactive · leetcode · math · monotonic-stack · sorting · stack · string · Last updated: Aug 2, 2025

Maximum Students Taking Exam

May 21, 2025 · 12 min · array · bit-manipulation · bitmask · database · dynamic-programming · leetcode · matrix · Last updated: Aug 2, 2025

Maximum Subarray Sum with One Deletion

May 21, 2025 · 4 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Maximum Sum BST in Binary Tree

May 21, 2025 · 6 min · array · binary-search-tree · binary-tree · depth-first-search · dynamic-programming · leetcode · string · tree · Last updated: Aug 2, 2025

Maximum Value of K Coins From Piles

May 21, 2025 · 11 min · array · dynamic-programming · leetcode · prefix-sum · Last updated: Aug 2, 2025

Median of K sorted array

May 21, 2025 · 5 min · median · k-sorted · heap · binary-search · Last updated: Aug 15, 2025

Min Cost to Connect All Points

May 21, 2025 · 13 min · array · binary-search-tree · binary-tree · database · design · graph · greedy · iterator · leetcode · minimum-spanning-tree · mst-minimum-spanning-tree · sorting · stack · string · tree · union-find · Last updated: Jul 31, 2025

Min Xor Value

May 21, 2025 · 3 min · interviewbit · bits · bucketing · Last updated: Aug 16, 2025

Minimize Max Distance to Gas Station

May 21, 2025 · 5 min · array · binary-search · leetcode · todo · Last updated: Aug 2, 2025

Minimize the Maximum Difference of Pairs

May 21, 2025 · 3 min · array · binary-search · breadth-first-search · dynamic-programming · greedy · heap-priority-queue · leetcode · matrix · monotonic-stack · search/binary · stack · union-find · Last updated: Aug 2, 2025

Minimum ASCII Delete Sum for Two Strings

May 21, 2025 · 6 min · dynamic-programming · leetcode · string · Last updated: Aug 2, 2025

Minimum Cost to Connect Two Groups of Points

May 21, 2025 · 7 min · array · binary-tree · bit-manipulation · bitmask · database · dynamic-programming · leetcode · matrix · stack · string · tree · Last updated: Aug 2, 2025

Minimum Cost to Cut a Stick

May 21, 2025 · 6 min · array · database · dynamic-programming · graph · leetcode · sorting · Last updated: Aug 2, 2025

Minimum Cost to Merge Stones

May 21, 2025 · 8 min · array · dynamic-programming · hash-table · leetcode · prefix-sum · Last updated: Aug 2, 2025

Minimum Deletions to Make Character Frequencies Unique

May 21, 2025 · 4 min · array · binary-search · greedy · hash-table · heap-priority-queue · leetcode · math · sorting · string · Last updated: Aug 2, 2025

Minimum Difficulty of a Job Schedule

May 21, 2025 · 12 min · array · binary-search · database · dynamic-programming · heap-priority-queue · leetcode · matrix · sorting · Last updated: Aug 2, 2025

Minimum Distance to Type a Word Using Two Fingers

May 21, 2025 · 8 min · database · dynamic-programming · leetcode · string · Last updated: Aug 2, 2025

Minimum Moves to Group Occupied Seats

May 21, 2025 · 5 min · interviewbit · greedy · Last updated: Aug 16, 2025

Minimum Number of Flips to Make the Binary String Alternating

May 21, 2025 · 7 min · dynamic-programming · greedy · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Minimum Number of Taps to Open to Water a Garden

May 21, 2025 · 6 min · array · database · dynamic-programming · greedy · leetcode · string · todo · Last updated: Aug 2, 2025

Minimum One Bit Operations to Make Integers Zero

May 21, 2025 · 3 min · binary-tree · bit-manipulation · counting · database · depth-first-search · dynamic-programming · hash-table · leetcode · memoization · tree · Last updated: Aug 2, 2025

Minimum Operations to Reduce X to Zero

May 21, 2025 · 12 min · array · binary-search · hash-table · inversion · leetcode · prefix-sum · sliding-window · Last updated: Aug 1, 2025

Minimum Score Triangulation of Polygon

May 21, 2025 · 5 min · array · breadth-first-search · depth-first-search · dynamic-programming · graph · leetcode · math · simulation · sorting · string · two-pointers · Last updated: Aug 2, 2025

Minimum Speed to Arrive on Time

May 21, 2025 · 7 min · array · binary-search · leetcode · Last updated: Aug 2, 2025

Minimum Swaps To Make Sequences Increasing

May 21, 2025 · 5 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Minimum Switch Presses to Light All Bulbs on Right

May 21, 2025 · 6 min · greedy · Last updated: Aug 2, 2025

Minimum Time to Collect All Apples in a Tree

May 21, 2025 · 6 min · breadth-first-search · depth-first-search · hash-table · leetcode · tree · Last updated: Jul 29, 2025

Multiplication of Two Numbers

May 21, 2025 · 2 min · multiplication · maths · Last updated: Jun 4, 2025

Network Delay Time

May 21, 2025 · 9 min · breadth-first-search · depth-first-search · graph · heap-priority-queue · leetcode · shortest-path · daily-coding-problem · Last updated: Aug 9, 2025

New 21 Game

May 21, 2025 · 5 min · dynamic-programming · leetcode · math · probability-and-statistics · sliding-window · Last updated: Aug 2, 2025

Next even permutation of a number

May 21, 2025 · 11 min · permutation-combination · Last updated: Jul 26, 2025

Noble Integer

May 21, 2025 · 3 min · interviewbit · Last updated: Aug 17, 2025

Non-negative Integers without Consecutive Ones

May 21, 2025 · 5 min · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Nth Smallest Element in Two Sorted Arrays

May 21, 2025 · 9 min · array · array-algo · median · k-sorted · k-smallest-largest · kth · Last updated: Jul 20, 2025

Number of Digit One

May 21, 2025 · 3 min · dynamic-programming · leetcode · math · recursion · todo · Last updated: Aug 2, 2025

Number of elements greater than K in the range L to R

May 21, 2025 · 8 min · fenwick-tree · array · Last updated: Aug 2, 2025

Number of Enclaves

May 21, 2025 · 4 min · array · breadth-first-search · depth-first-search · dfs · leetcode · matrix · union-find · Last updated: Jul 29, 2025

Number of Islands II

May 21, 2025 · 5 min · array · hash-table · leetcode · matrix · union-find · Last updated: Jul 29, 2025

Number of Longest Increasing Subsequence

May 21, 2025 · 6 min · array · binary-indexed-tree · dynamic-programming · leetcode · lis-longest-increasing-subsequence · segment-tree · todo · Last updated: Jun 19, 2025

Number of Music Playlists

May 21, 2025 · 11 min · combinatorics · dynamic-programming · leetcode · math · Last updated: Aug 10, 2025

Number of Paths with Max Score

May 21, 2025 · 8 min · array · dynamic-programming · leetcode · matrix · todo · Last updated: Aug 2, 2025

Number of Restricted Paths From First to Last Node

May 21, 2025 · 9 min · array · bit-manipulation · database · dynamic-programming · graph · greedy · hash-table · heap-priority-queue · leetcode · prefix-sum · shortest-path · topological-sort · Last updated: Aug 2, 2025

Number of Sets of K Non-Overlapping Line Segments

May 21, 2025 · 5 min · combinatorics · dynamic-programming · leetcode · math · todo · Last updated: Aug 2, 2025

Number of Ways to Rearrange Sticks With K Sticks Visible

May 21, 2025 · 12 min · array · combinatorics · database · dynamic-programming · leetcode · math · string · two-pointers · Last updated: Aug 2, 2025

Number of Ways to Wear Different Hats to Each Other

May 21, 2025 · 6 min · array · bit-manipulation · bitmask · database · dynamic-programming · hash-table · leetcode · string · Last updated: Aug 2, 2025

Numbers At Most N Given Digit Set

May 21, 2025 · 6 min · array · binary-search · dynamic-programming · leetcode · math · string · Last updated: Aug 2, 2025

Numbers Of Length N and Values Less Than K

May 21, 2025 · 5 min · interviewbit · maths · combinatorics · digits · dynamic-programming · Last updated: Aug 18, 2025

Numbers With Repeated Digits

May 21, 2025 · 8 min · array · bit-manipulation · dynamic-programming · greedy · hash-table · leetcode · linked-list · math · monotonic-stack · stack · string · Last updated: Aug 2, 2025

OOP - Inheritance Vs Composition

May 21, 2025 · 3 min · Last updated: Aug 11, 2025

Palindrome Permutation II

May 21, 2025 · 7 min · backtracking · hash-table · leetcode · palindrome · string · Last updated: Jul 31, 2025

Partitioning Into Minimum Number Of Deci-Binary Numbers

May 21, 2025 · 4 min · greedy · leetcode · numerical-algo · string · Last updated: Aug 1, 2025

Path With Minimum Effort

May 21, 2025 · 8 min · array · bfs · binary-search · breadth-first-search · database · depth-first-search · graph · heap-priority-queue · leetcode · linked-list · math · matrix · sorting · todo · topological-sort · two-pointers · union-find · Last updated: Aug 2, 2025

Permutation Rank

May 21, 2025 · 4 min · permutation-combination · Last updated: Jul 26, 2025

Pizza With 3n Slices

May 21, 2025 · 5 min · array · breadth-first-search · depth-first-search · dynamic-programming · greedy · heap-priority-queue · leetcode · math · matrix · simulation · todo · union-find · Last updated: Aug 2, 2025

Poor Pigs

May 21, 2025 · 3 min · combinatorics · dynamic-programming · leetcode · math · permutation-combination · Last updated: Aug 1, 2025

Prims Algorithm Using Adjacency List and Priority Queue

May 21, 2025 · 3 min · Last updated: Jul 30, 2025

Prims Algorithms Using Adjacency Matrix

May 21, 2025 · 3 min · Last updated: Aug 2, 2025

Print Expression Tree Graphically

May 21, 2025 · 4 min · Last updated: Aug 2, 2025

Process Tasks Using Servers

May 21, 2025 · 10 min · array · binary-search · database · dynamic-programming · greedy · hash-table · heap · heap-priority-queue · leetcode · math · matrix · prefix-sum · sliding-window · sorting · string · two-pointers · Last updated: Aug 2, 2025

Queue Reconstruction by Height

May 21, 2025 · 14 min · array · binary-indexed-tree · greedy · interviewbit · leetcode · segment-tree · sorting · Last updated: Jun 3, 2025

Race Car

May 21, 2025 · 6 min · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Random Pick with Weight

May 21, 2025 · 4 min · array · binary-search · design/data-structure · leetcode · math · prefix-sum · randomized · Last updated: Jul 27, 2025

Reachable Nodes In Subdivided Graph

May 21, 2025 · 9 min · graph · heap-priority-queue · leetcode · shortest-path · Last updated: Aug 2, 2025

Reaching Points

May 21, 2025 · 9 min · leetcode · math · Last updated: Aug 1, 2025

Rearranging Array Elements by Index Mapping

May 21, 2025 · 3 min · interviewbit · modulo-operator · maths · Last updated: Aug 18, 2025

Reduce Array Size to The Half

May 21, 2025 · 4 min · array · greedy · hash-table · heap-priority-queue · leetcode · queue/priority · sorting · Last updated: Aug 2, 2025

Redundant Braces

May 21, 2025 · 3 min · interviewbit · stack · parentheses · Last updated: Aug 18, 2025

Remove All Adjacent Duplicates in String 2

May 21, 2025 · 3 min · array · breadth-first-search · database · duplicates-algo · leetcode · matrix · stack · string · Last updated: Jul 29, 2025

Remove Palindromic Subsequences

May 21, 2025 · 5 min · array · leetcode · palindrome · puzzle · sorting · string · subsequence · two-pointers · Last updated: Aug 2, 2025

Reorder Data in Log Files

May 21, 2025 · 5 min · array · leetcode · sorting · string · string-algo · Last updated: Aug 2, 2025

Reorder Routes to Make All Paths Lead to the City Zero

May 21, 2025 · 8 min · array · backtracking · binary-tree · breadth-first-search · combinatorics · database · depth-first-search · dynamic-programming · graph · leetcode · math · probability-and-statistics · tree · Last updated: Aug 3, 2025

Restore The Array

May 21, 2025 · 10 min · array · counting · dynamic-programming · hash-table · leetcode · ordered-set · sorting · string · todo · Last updated: Aug 2, 2025

Russian Doll Envelopes

May 21, 2025 · 9 min · array · binary-search · dynamic-programming · leetcode · search/binary · sorting · Last updated: Aug 2, 2025

Seat Reservation Manager

May 21, 2025 · 3 min · design · design/data-structure · heap-priority-queue · leetcode · Last updated: Jul 27, 2025

Self Crossing

May 21, 2025 · 5 min · array · geometry · hash-table · leetcode · math · Last updated: Aug 1, 2025

Shopping Offers

May 21, 2025 · 7 min · array · backtracking · bit-manipulation · bitmask · dynamic-programming · leetcode · memoization · Last updated: Aug 2, 2025

Shortest Bridge

May 21, 2025 · 8 min · array · bfs · breadth-first-search · depth-first-search · dfs · graph · leetcode · matrix · Last updated: Aug 2, 2025

Shortest Distance from All Buildings

May 21, 2025 · 11 min · array · breadth-first-search · leetcode · matrix · shortest-path · Last updated: Aug 1, 2025

Shortest Path Visiting All Nodes

May 21, 2025 · 6 min · bit-manipulation · bitmask · breadth-first-search · dynamic-programming · graph · leetcode · Last updated: Aug 2, 2025

Shuffle an Array

May 21, 2025 · 5 min · array · design · design/data-structure · leetcode · math · randomized · randomized-algo · reservoir-sampling · Last updated: Aug 2, 2025

Single-Threaded CPU

May 21, 2025 · 9 min · array · bit-manipulation · greedy · heap-priority-queue · heap/min · leetcode · math · sorting · Last updated: Aug 2, 2025

Smallest Range Covering Elements from K Lists

May 21, 2025 · 12 min · array · greedy · hash-table · heap · heap-priority-queue · leetcode · sliding-window · sorting · array-algo · shortest-path · k-sorted · Last updated: Aug 2, 2025

Smallest String With Swaps

May 21, 2025 · 7 min · array · breadth-first-search · database · depth-first-search · graph · hash-table · leetcode · sorting · string · topological-sort · union-find · Last updated: Aug 2, 2025

Smallest Sufficient Team

May 21, 2025 · 7 min · array · bit-manipulation · bitmask · counting · database · dynamic-programming · hash-table · leetcode · Last updated: Aug 2, 2025

Sort a nearly sorted K sorted array

May 21, 2025 · 6 min · daily-coding-problem · heap · sorting · Last updated: Aug 10, 2025

Sort Array By Parity

May 21, 2025 · 3 min · array · leetcode · sorting · two-pointers · Last updated: Aug 2, 2025

Sort Transformed Array

May 21, 2025 · 6 min · array · leetcode · math · sorting · two-pointers · Last updated: Aug 2, 2025

Soup Servings

May 21, 2025 · 6 min · dynamic-programming · leetcode · math · probability-and-statistics · Last updated: Aug 2, 2025

Split Array into Consecutive Subsequences

May 21, 2025 · 8 min · array · greedy · hash-table · hashing · heap-priority-queue · leetcode · Last updated: Jul 27, 2025

Split Two Strings to Make Palindrome

May 21, 2025 · 6 min · array · binary-search · bit-manipulation · bitmask · dynamic-programming · enumeration · interactive · leetcode · sorting · string · todo · tree · two-pointers · Last updated: Aug 2, 2025

Splitting a String Into Descending Consecutive Values

May 21, 2025 · 6 min · backtracking · greedy · leetcode · string · two-pointers · Last updated: Aug 2, 2025

Stone Game III

May 21, 2025 · 6 min · array · dynamic-programming · game-theory · leetcode · math · todo · Last updated: Aug 2, 2025

Stone Game IV

May 21, 2025 · 4 min · dynamic-programming · game-theory · leetcode · math · todo · Last updated: Aug 2, 2025

Stone Game V

May 21, 2025 · 7 min · array · database · dynamic-programming · enumeration · game-theory · greedy · leetcode · math · sorting · Last updated: Aug 2, 2025

Stone Game VII

May 21, 2025 · 5 min · array · dynamic-programming · game-theory · leetcode · math · Last updated: Aug 2, 2025

Strassen Matrix Multiplication Algorithm

May 21, 2025 · 3 min · divide-n-conquer · matrix · numerical-algo · multiplication · todo/merge-2-notes · Last updated: Aug 2, 2025

Successful Pairs of Spells and Potions

May 21, 2025 · 6 min · array · backtracking · binary-search · bit-manipulation · bitmask · dynamic-programming · hash-table · leetcode · matrix · prefix-sum · simulation · sliding-window · sorting · string · string-matching · two-pointers · Last updated: Aug 2, 2025

Sum of Pairwise Hamming Distances

May 21, 2025 · 5 min · interviewbit · Last updated: Aug 18, 2025

Swim in Rising Water

May 21, 2025 · 8 min · array · binary-search · breadth-first-search · depth-first-search · graph · heap-priority-queue · leetcode · matrix · union-find · Last updated: Aug 2, 2025

Tallest Billboard

May 21, 2025 · 4 min · array · dynamic-programming · leetcode · todo · Last updated: Aug 2, 2025

The Number of Weak Characters in the Game

May 21, 2025 · 3 min · array · dynamic-programming · enumeration · greedy · leetcode · math · monotonic-stack · number-theory · sorting · stack · union-find · Last updated: Aug 2, 2025

Third Maximum Number

May 21, 2025 · 6 min · array · leetcode · sorting · Last updated: Aug 2, 2025

Triples with Bitwise AND Equal To Zero

May 21, 2025 · 5 min · array · bit-manipulation · hash-table · leetcode · todo · Last updated: Aug 2, 2025

Two City Scheduling

May 21, 2025 · 3 min · array · brainteaser · breadth-first-search · data-stream · depth-first-search · design · dynamic-programming · geometry · greedy · hash-table · leetcode · math · matrix · sliding-window · sorting · string · trie · Last updated: Aug 2, 2025

Unbounded Knapsack Problem

May 21, 2025 · 13 min · dynamic-programming · Last updated: Jun 17, 2025

Unique Paths in Grid without crossing main diagonal

May 21, 2025 · 11 min · pramp · Last updated: Jul 24, 2025

Unique Substrings in Wraparound String

May 21, 2025 · 4 min · dynamic-programming · leetcode · string · todo · Last updated: Jul 31, 2025

Valid Permutations for DI Sequence

May 21, 2025 · 6 min · dynamic-programming · leetcode · prefix-sum · string · Last updated: Aug 2, 2025

Video Stitching

May 21, 2025 · 5 min · array · dynamic-programming · greedy · leetcode · Last updated: Aug 2, 2025

Walls and Gates

May 21, 2025 · 12 min · array · backtracking · breadth-first-search · leetcode · matrix · path-finding · Last updated: Jul 30, 2025

Water and Jug

May 21, 2025 · 16 min · breadth-first-search · depth-first-search · dynamic-programming · leetcode · math · Last updated: Aug 2, 2025

Wave Sort

May 21, 2025 · 3 min · interviewbit · Last updated: Jun 3, 2025

Wiggle Sort 2 - No Adjacent Duplicates

May 21, 2025 · 5 min · array · divide-and-conquer · duplicates-algo · greedy · leetcode · partition · quickselect · quicksort · rearrange-array · sorting · Last updated: Jun 3, 2025

Wiggle Subsequence

May 21, 2025 · 5 min · array · dynamic-programming · greedy · leetcode · Last updated: Aug 2, 2025

Word Ladder - Get shortest ladder

May 21, 2025 · 6 min · ctci · convert · string-algo · transformation · edit-distance · Last updated: Jun 22, 2025

Word Ladder - Get shortest ladder by changing, adding or removing one letter at a time

May 21, 2025 · 6 min · convert · word · string-algo · design · algorithm · Last updated: Jun 22, 2025

Word Ladder 0 - Is a ladder there

May 21, 2025 · 2 min · word · dfs · Last updated: Aug 2, 2025

Painting a Grid With Three Different Colors

May 18, 2025 · 5 min · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Longest Unequal Adjacent Groups Subsequence II

May 16, 2025 · 5 min · array · dynamic-programming · leetcode · string · Last updated: Aug 2, 2025

Longest Unequal Adjacent Groups Subsequence I

May 15, 2025 · 3 min · array · dynamic-programming · greedy · leetcode · string · Last updated: Aug 2, 2025

Total Characters in String After Transformations II

May 14, 2025 · 7 min · counting · dynamic-programming · hash-table · leetcode · math · string · Last updated: Aug 2, 2025

Total Characters in String After Transformations I

May 13, 2025 · 4 min · counting · dynamic-programming · hash-table · leetcode · math · string · Last updated: Aug 2, 2025

Finding 3-Digit Even Numbers

May 12, 2025 · 3 min · array · enumeration · hash-table · leetcode · sorting · Last updated: Aug 2, 2025

Count Number of Balanced Permutations

May 9, 2025 · 9 min · combinatorics · dynamic-programming · leetcode · math · string · Last updated: Aug 2, 2025

Find Minimum Time to Reach Last Room II

May 8, 2025 · 6 min · array · graph · heap-priority-queue · leetcode · matrix · shortest-path · Last updated: Jul 31, 2025

Find Minimum Time to Reach Last Room I

May 7, 2025 · 5 min · array · graph · heap-priority-queue · leetcode · matrix · shortest-path · Last updated: Jul 31, 2025

Minimum Domino Rotations For Equal Row

May 3, 2025 · 4 min · array · greedy · leetcode · Last updated: Aug 2, 2025

Push Dominoes

May 2, 2025 · 13 min · dynamic-programming · leetcode · string · two-pointers · Last updated: Aug 9, 2025

Maximum Number of Tasks You Can Assign

May 1, 2025 · 6 min · array · binary-search · greedy · leetcode · monotonic-queue · queue · sorting · Last updated: Aug 2, 2025

April ³³

Count Subarrays With Score Less Than K

April 28, 2025 · 4 min · array · binary-search · leetcode · prefix-sum · sliding-window · Last updated: Aug 2, 2025

Count Subarrays With Fixed Bounds

April 26, 2025 · 3 min · array · binary-tree · breadth-first-search · depth-first-search · leetcode · math · monotonic-queue · number-theory · queue · sliding-window · string · tree · Last updated: Aug 2, 2025

Count of Interesting Subarrays

April 25, 2025 · 5 min · array · hash-table · leetcode · prefix-sum · Last updated: Aug 2, 2025

Count Complete Subarrays in an Array

April 24, 2025 · 3 min · array · hash-table · leetcode · sliding-window · Last updated: Aug 2, 2025

Count Largest Group

April 23, 2025 · 3 min · hash-table · leetcode · math · Last updated: Aug 2, 2025

Count the Number of Ideal Arrays

April 22, 2025 · 5 min · combinatorics · dynamic-programming · leetcode · math · number-theory · Last updated: Jul 31, 2025

Count the Hidden Sequences

April 21, 2025 · 4 min · array · leetcode · prefix-sum · Last updated: Aug 2, 2025

Rabbits in Forest

April 20, 2025 · 3 min · array · greedy · hash-table · leetcode · math · Last updated: Aug 2, 2025

Count Equal and Divisible Pairs in an Array

April 17, 2025 · 3 min · array · leetcode · Last updated: Aug 2, 2025

Count the Number of Good Subarrays

April 16, 2025 · 3 min · array · hash-table · leetcode · sliding-window · Last updated: Aug 2, 2025

Count Good Triplets in an Array

April 15, 2025 · 5 min · array · binary-indexed-tree · binary-search · divide-and-conquer · leetcode · math · merge-sort · ordered-set · segment-tree · simulation · todo · Last updated: Aug 2, 2025

Count Good Triplets

April 14, 2025 · 3 min · array · enumeration · leetcode · Last updated: Aug 2, 2025

Find the Count of Good Integers

April 12, 2025 · 5 min · combinatorics · enumeration · hash-table · leetcode · math · Last updated: Aug 2, 2025

Coins In a Line Game

April 9, 2025 · 5 min · daily-coding-problem · dynamic-programming · coin · Last updated: Aug 2, 2025

Smallest positive integer that cannot be represented as the sum of a subset of a sorted array

April 9, 2025 · 3 min · daily-coding-problem · Last updated: Aug 2, 2025

Find the nth sevenish number

April 9, 2025 · 3 min · daily-coding-problem · Last updated: Jun 4, 2025

Design and implement Connect 4

April 9, 2025 · 5 min · daily-coding-problem · Last updated: Aug 2, 2025

Reverse a directed graph

April 9, 2025 · 4 min · daily-coding-problem · Last updated: Aug 2, 2025

Count Subarrays of Length Three With a Condition

April 9, 2025 · 2 min · leetcode · Last updated: Aug 2, 2025

Minimum Operations to Make Array Values Equal to K

April 9, 2025 · 3 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

Range Frequency Queries

April 9, 2025 · 3 min · array · binary-search · design · enumeration · hash-table · leetcode · math · segment-tree · todo · Last updated: Aug 2, 2025

Build Array from Permutation

April 9, 2025 · 2 min · array · leetcode · simulation · Last updated: Aug 2, 2025

Count of Range Sum

April 9, 2025 · 10 min · array · binary-indexed-tree · binary-search · count · divide-and-conquer · leetcode · merge-sort · ordered-set · segment-tree · subarray · subarray-sum · sum · Last updated: Aug 2, 2025

Domino and Tromino Tiling

April 9, 2025 · 14 min · dynamic-programming · leetcode · todo · Last updated: Aug 10, 2025

Online Majority Element In Subarray

April 9, 2025 · 4 min · array · binary-indexed-tree · binary-search · counting · database · design · hash-table · leetcode · segment-tree · string · todo · Last updated: Aug 2, 2025

Range Sum Query 2D - Mutable

April 9, 2025 · 4 min · array · binary-indexed-tree · design · leetcode · matrix · segment-tree · Last updated: Aug 2, 2025

Super Egg Drop

April 9, 2025 · 4 min · binary-search · dynamic-programming · leetcode · math · Last updated: Aug 2, 2025

Type of Triangle

April 9, 2025 · 3 min · array · leetcode · math · sorting · Last updated: Jul 31, 2025

Minimum Number of Operations to Make Elements in Array Distinct

April 8, 2025 · 3 min · hash-table · leetcode · Last updated: Aug 2, 2025

Lowest Common Ancestor of Deepest Leaves

April 4, 2025 · 4 min · binary-tree · breadth-first-search · depth-first-search · hash-table · leetcode · traversal/postorder · tree · Last updated: Aug 2, 2025

Maximum Value of an Ordered Triplet II

April 3, 2025 · 6 min · array · leetcode · Last updated: Aug 2, 2025

Maximum Value of an Ordered Triplet I

April 2, 2025 · 3 min · array · leetcode · Last updated: Aug 2, 2025

Solving Questions With Brainpower

April 1, 2025 · 4 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

March ³⁰

Put Marbles in Bags

March 31, 2025 · 4 min · array · binary-indexed-tree · binary-search · breadth-first-search · depth-first-search · dynamic-programming · enumeration · greedy · hash-table · heap-priority-queue · leetcode · matrix · prefix-sum · simulation · sliding-window · sorting · string · two-pointers · Last updated: Aug 2, 2025

Apply Operations to Maximize Score

March 29, 2025 · 9 min · array · greedy · leetcode · math · monotonic-stack · number-theory · stack · Last updated: Jul 31, 2025

Maximum Number of Points From Grid Queries

March 28, 2025 · 5 min · array · breadth-first-search · heap-priority-queue · leetcode · matrix · sorting · two-pointers · union-find · Last updated: Aug 2, 2025

Features of Java

March 27, 2025 · 2 min · Last updated: Mar 27, 2025

Minimum Operations to Make a Uni-Value Grid

March 26, 2025 · 3 min · array · data-stream · design · hash-table · heap-priority-queue · leetcode · math · matrix · ordered-set · sorting · Last updated: Aug 2, 2025

Check if Grid can be Cut into Sections

March 25, 2025 · 4 min · interval · leetcode · Last updated: Aug 2, 2025

Minimum in a Binary Tree

March 25, 2025 · 4 min · bt-binary-tree · Last updated: Aug 2, 2025

Count Days Without Meetings

March 24, 2025 · 8 min · array · leetcode · sorting · Last updated: Aug 2, 2025

Number of Ways to Arrive at Destination

March 23, 2025 · 5 min · dynamic-programming · graph · leetcode · shortest-path · topological-sort · Last updated: Jul 31, 2025

Count the Number of Complete Components

March 22, 2025 · 4 min · breadth-first-search · depth-first-search · graph · leetcode · union-find · Last updated: Aug 2, 2025

Find All Possible Recipes from Given Supplies

March 21, 2025 · 4 min · array · graph · hash-table · leetcode · string · topological-sort · Last updated: Aug 2, 2025

Minimum Cost Walk in Weighted Graph

March 20, 2025 · 6 min · array · bit-manipulation · graph · leetcode · union-find · Last updated: Aug 2, 2025

Minimum Operations to Make Binary Array Elements Equal to One I

March 19, 2025 · 3 min · array · bit-manipulation · leetcode · prefix-sum · queue · sliding-window · Last updated: Aug 2, 2025

Longest Nice Subarray

March 18, 2025 · 3 min · array · bit-manipulation · leetcode · sliding-window · Last updated: Aug 2, 2025

Divide Array Into Equal Pairs

March 17, 2025 · 2 min · array · bit-manipulation · counting · hash-table · leetcode · Last updated: Aug 2, 2025

Minimum Time to Repair Cars

March 16, 2025 · 4 min · array · binary-search · leetcode · Last updated: Aug 2, 2025

Flatten binary search tree to sorted linked list

March 14, 2025 · 3 min · Last updated: Aug 2, 2025

Maximum Candies Allocated to K Children

March 14, 2025 · 5 min · array · binary-search · leetcode · Last updated: Aug 2, 2025

Zero Array Transformation 3

March 13, 2025 · 5 min · array · greedy · heap-priority-queue · leetcode · prefix-sum · sorting · Last updated: Aug 2, 2025

Zero Array Transformation 2

March 13, 2025 · 6 min · array · binary-search · leetcode · prefix-sum · Last updated: Aug 2, 2025

Zero Array Transformation 1

March 13, 2025 · 5 min · array · leetcode · prefix-sum · Last updated: Aug 2, 2025

Maximum Count of Positive Integer and Negative Integer

March 12, 2025 · 4 min · array · binary-search · counting · leetcode · Last updated: Aug 2, 2025

Number of Substrings Containing All Three Characters

March 11, 2025 · 3 min · hash-table · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Alternating Groups 2

March 9, 2025 · 4 min · array · leetcode · sliding-window · Last updated: Aug 2, 2025

Closest Prime Numbers in Range

March 7, 2025 · 4 min · leetcode · math · number-theory · Last updated: Jul 31, 2025

Find Missing and Repeated Values

March 6, 2025 · 3 min · array · hash-table · leetcode · math · matrix · Last updated: Aug 2, 2025

Count Total Number of Colored Cells

March 5, 2025 · 3 min · leetcode · math · Last updated: Jul 31, 2025

Check if Number is a Sum of Powers of Three

March 4, 2025 · 4 min · leetcode · math · Last updated: Jul 31, 2025

Merge Two 2D Arrays by Summing Values

March 2, 2025 · 4 min · array · hash-table · leetcode · two-pointers · Last updated: Aug 2, 2025

Apply Operations to an Array

March 1, 2025 · 7 min · array · leetcode · simulation · two-pointers · video · Last updated: Aug 2, 2025

February ²⁸

Length of Longest Fibonacci Subsequence

February 27, 2025 · 8 min · array · dynamic-programming · fibonacci · hash-table · leetcode · video · Last updated: Aug 2, 2025

Maximum Absolute Sum of Any Subarray

February 26, 2025 · 6 min · array · dynamic-programming · kadane · leetcode · video · Last updated: Aug 2, 2025

Number of Sub-arrays With Odd Sum

February 25, 2025 · 5 min · array · dynamic-programming · leetcode · math · prefix-sum · video · Last updated: Aug 2, 2025

Most Profitable Path in a Tree

February 24, 2025 · 9 min · array · breadth-first-search · depth-first-search · graph · leetcode · tree · video · Last updated: Aug 2, 2025

Construct Binary Tree from Preorder and Postorder Traversal

February 23, 2025 · 6 min · array · binary-tree · divide-and-conquer · hash-table · leetcode · tree · Last updated: Aug 2, 2025

Recover a Tree From Preorder Traversal

February 22, 2025 · 4 min · binary-tree · depth-first-search · leetcode · string · tree · video · Last updated: Aug 2, 2025

Find Unique Binary String

February 20, 2025 · 8 min · array · backtracking · divide-and-conquer · dynamic-programming · hash-table · leetcode · matrix · prefix-sum · string · video · Last updated: Aug 2, 2025

The k-th Lexicographical String of All Happy Strings of Length n

February 19, 2025 · 9 min · backtracking · leetcode · string · video · Last updated: Aug 2, 2025

Letter Tile Possibilities

February 17, 2025 · 6 min · backtracking · counting · hash-table · leetcode · sorting · string · video · Last updated: Aug 2, 2025

Lazy Caterer’s sequence

February 15, 2025 · 3 min · maths · puzzle · Last updated: Mar 12, 2025

Find the Punishment Number of an Integer

February 15, 2025 · 4 min · backtracking · leetcode · math · video · Last updated: Aug 2, 2025

Product of the Last K Numbers

February 14, 2025 · 3 min · array · data-stream · design · leetcode · math · queue · video · Last updated: Aug 2, 2025

Minimum Operations to Exceed Threshold Value 2

February 13, 2025 · 4 min · array · heap-priority-queue · leetcode · simulation · video · Last updated: Aug 2, 2025

Remove All Occurrences of a Substring

February 11, 2025 · 7 min · leetcode · simulation · stack · string · video · Last updated: Aug 2, 2025

Count Number of Bad Pairs

February 9, 2025 · 4 min · array · counting · hash-table · leetcode · math · video · Last updated: Aug 2, 2025

Design a Number Container System

February 8, 2025 · 7 min · design · hash-table · heap-priority-queue · leetcode · ordered-set · video · Last updated: Aug 2, 2025

Smallest sparse number greater than or equal to N

February 7, 2025 · 3 min · daily-coding-problem · Last updated: Aug 2, 2025

Find the Number of Distinct Colors Among the Balls

February 7, 2025 · 7 min · array · hash-table · leetcode · simulation · video · Last updated: Aug 2, 2025

Length of the Longest Consecutive 1s in Binary Representation

February 6, 2025 · 2 min · daily-coding-problem · Last updated: Aug 2, 2025

Find All Occurrences of the Pattern in the String

February 6, 2025 · 5 min · daily-coding-problem · Last updated: Aug 2, 2025

Collatz Sequence

February 6, 2025 · 4 min · daily-coding-problem · Last updated: Jul 31, 2025

Tuple with Same Product

February 6, 2025 · 5 min · array · counting · hash-table · leetcode · video · Last updated: Aug 2, 2025

Clear Digits

February 5, 2025 · 7 min · leetcode · simulation · stack · string · video · Last updated: Aug 2, 2025

Maximum Ascending Subarray Sum

February 4, 2025 · 4 min · array · leetcode · video · Last updated: Aug 2, 2025

Permutation of Array using given order

February 3, 2025 · 2 min · daily-coding-problem · Last updated: Aug 2, 2025

Next Permutation of Integer

February 3, 2025 · 3 min · daily-coding-problem · Last updated: Aug 2, 2025

Longest Strictly Increasing or Strictly Decreasing Subarray

February 3, 2025 · 4 min · array · leetcode · video · Last updated: Aug 2, 2025

Check if Array Is Sorted and Rotated

February 2, 2025 · 9 min · array · leetcode · video · Last updated: Aug 2, 2025

January ⁸⁰

Making A Large Island

January 31, 2025 · 5 min · array · breadth-first-search · depth-first-search · leetcode · matrix · union-find · Last updated: Aug 2, 2025

Divide Nodes Into the Maximum Number of Groups

January 30, 2025 · 6 min · breadth-first-search · graph · leetcode · union-find · Last updated: Aug 2, 2025

Maximum Number of Fish in a Grid

January 28, 2025 · 4 min · array · breadth-first-search · depth-first-search · leetcode · matrix · union-find · video · Last updated: Aug 2, 2025

Maximum Employees to Be Invited to a Meeting

January 26, 2025 · 7 min · depth-first-search · graph · leetcode · topological-sort · Last updated: Aug 2, 2025

Balance Parentheses with Minimum Insertions and Deletions

January 25, 2025 · 3 min · daily-coding-problem · Last updated: Aug 2, 2025

Make Lexicographically Smallest Array by Swapping Elements

January 25, 2025 · 6 min · array · leetcode · sorting · union-find · Last updated: Aug 2, 2025

Count elements in range in sorted matrix

January 25, 2025 · 5 min · daily-coding-problem · binary-search · Last updated: Aug 2, 2025

Longest subarray with distinct elements

January 24, 2025 · 3 min · daily-coding-problem · sliding-window · Last updated: Aug 2, 2025

Fix the variable capture in closure

January 24, 2025 · 2 min · daily-coding-problem · Last updated: Jan 24, 2025

Check if any pair of rectangles overlap

January 24, 2025 · 4 min · daily-coding-problem · Last updated: Jul 31, 2025

Divide array into two subsets with minimum difference

January 23, 2025 · 4 min · daily-coding-problem · Last updated: Aug 2, 2025

Area of intersection of two rectangles

January 23, 2025 · 3 min · daily-coding-problem · Last updated: Jul 31, 2025

Count Servers that Communicate

January 23, 2025 · 4 min · array · breadth-first-search · counting · depth-first-search · leetcode · matrix · union-find · video · Last updated: Aug 2, 2025

Check if a graph is minimally-connected

January 22, 2025 · 3 min · daily-coding-problem · Last updated: Aug 2, 2025

Split string into fewest palindromic substrings

January 22, 2025 · 4 min · daily-coding-problem · Last updated: Aug 2, 2025

Alice Joins Probability Student Club by Calculating Expected Values of Probabilistic Games

January 22, 2025 · 4 min · daily-coding-problem · Last updated: Jul 31, 2025

Ad-hoc Polymorphism

January 22, 2025 · 1 min ·

Describe and give an example of Ad-hoc, Parametric and Subtype polymorphism

January 22, 2025 · 1 min · daily-coding-problem ·

Parametric Polymorphism

January 22, 2025 · 1 min · Last updated: Jan 22, 2025

Run a Markov chain and count state visits

January 22, 2025 · 4 min · daily-coding-problem · Last updated: Jul 31, 2025

Subtype Polymorphism

January 22, 2025 · 1 min · Last updated: Jan 22, 2025

Map of Highest Peak

January 22, 2025 · 4 min · array · breadth-first-search · leetcode · matrix · video · Last updated: Aug 2, 2025

Construct Binary Search Tree BST from Postorder Traversal

January 21, 2025 · 3 min · daily-coding-problem · Last updated: Aug 2, 2025

Flatten a nested dictionary

January 21, 2025 · 3 min · daily-coding-problem · Last updated: Aug 2, 2025

Busiest period in a building

January 21, 2025 · 4 min · daily-coding-problem · Last updated: Aug 2, 2025

Grid Game

January 21, 2025 · 6 min · array · leetcode · matrix · prefix-sum · video · Last updated: Aug 2, 2025

Sort a linked list in O(n log n) time and constant space

January 20, 2025 · 1 min · daily-coding-problem · Last updated: Aug 2, 2025

Implement a 2D iterator class

January 20, 2025 · 3 min · daily-coding-problem · Last updated: Aug 2, 2025

Length of the longest path in a weighted tree

January 20, 2025 · 4 min · daily-coding-problem · Last updated: Aug 2, 2025

First Completely Painted Row or Column

January 20, 2025 · 5 min · array · hash-table · leetcode · matrix · video · Last updated: Aug 2, 2025

Minimum Cost to Make at Least One Valid Path in a Grid

January 18, 2025 · 5 min · array · breadth-first-search · database · graph · heap-priority-queue · leetcode · matrix · shortest-path · Last updated: Jul 31, 2025

Neighboring Bitwise XOR

January 17, 2025 · 4 min · array · bit-manipulation · leetcode · video · Last updated: Aug 2, 2025

Bitwise XOR of All Pairings

January 16, 2025 · 3 min · array · bit-manipulation · brainteaser · leetcode · video · Last updated: Aug 2, 2025

Minimize XOR

January 15, 2025 · 5 min · bit-manipulation · greedy · leetcode · video · Last updated: Aug 2, 2025

Generate random numbers from list based on given probabilities

January 14, 2025 · 2 min · daily-coding-problem · Last updated: Aug 2, 2025

Sort a list using reverse sublist operation

January 14, 2025 · 3 min · daily-coding-problem · Last updated: Aug 2, 2025

Find the Prefix Common Array of Two Arrays

January 14, 2025 · 7 min · array · bit-manipulation · hash-table · leetcode · video · Last updated: Aug 2, 2025

Minimum Length of String After Operations

January 13, 2025 · 3 min · counting · hash-table · leetcode · string · video · Last updated: Aug 2, 2025

Check if a Parentheses String Can Be Valid

January 12, 2025 · 8 min · greedy · leetcode · stack · string · Last updated: Aug 2, 2025

Construct K Palindrome Strings

January 11, 2025 · 3 min · counting · geometry · greedy · hash-table · leetcode · math · string · video · Last updated: Aug 2, 2025

Find Missing 1000 Numbers in Large Range

January 11, 2025 · 4 min · daily-coding-problem ·

Explaining Web Cookies to Non-Technical Person

January 11, 2025 · 2 min · daily-coding-problem ·

Explaining API vs SDK to Non-Technical Person

January 11, 2025 · 3 min · daily-coding-problem ·

Decrypt XOR-Encoded Hexadecimal String

January 11, 2025 · 17 min · daily-coding-problem ·

Decode Base64 String to Hex

January 11, 2025 · 13 min · daily-coding-problem ·

Convert Hex String to Base64

January 11, 2025 · 13 min · daily-coding-problem ·

Find Closest Coin by Manhattan Distance

January 11, 2025 · 11 min · daily-coding-problem ·

Count Digits Without Loops

January 11, 2025 · 10 min · daily-coding-problem ·

Solve System of Linear Addition Equations

January 11, 2025 · 34 min · daily-coding-problem ·

Calculate Courier Active Time from Event Logs

January 11, 2025 · 11 min · daily-coding-problem · Last updated: Aug 12, 2025

Key-Value Store with Max Key Query

January 11, 2025 · 13 min · daily-coding-problem ·

Merge Two Sorted Iterators

January 11, 2025 · 13 min · daily-coding-problem ·

Implement Quack Data Structure with Three Stacks

January 11, 2025 · 12 min · daily-coding-problem ·

Alternating Add-Subtract Curried Function

January 11, 2025 · 10 min · daily-coding-problem ·

Validate Mastermind Game Guesses

January 11, 2025 · 17 min · daily-coding-problem ·

Interleave Ranked Song Lists for Playlist

January 11, 2025 · 11 min · daily-coding-problem ·

Reconstruct Numbers from Anagrammed String

January 10, 2025 · 9 min · daily-coding-problem ·

Binary Tree Depth from Parenthesized String Representation

January 10, 2025 · 8 min · daily-coding-problem · Last updated: Aug 12, 2025

Queue using Set of Fixed-Length Arrays

January 10, 2025 · 10 min · daily-coding-problem · queue · array · netflix · Last updated: Aug 10, 2025

Word Subsets

January 10, 2025 · 4 min · array · hash-table · leetcode · string · video · Last updated: Aug 2, 2025

Nearest larger number for index in an array

January 9, 2025 · 3 min · daily-coding-problem · two-pointers · Last updated: Aug 2, 2025

Counting Words With a Given Prefix

January 9, 2025 · 2 min · array · leetcode · string · string-matching · video · Last updated: Aug 2, 2025

Implement 3 stacks in 1 list

January 8, 2025 · 3 min · daily-coding-problem · Last updated: Aug 2, 2025

Implement a bit array

January 8, 2025 · 3 min · daily-coding-problem · design · Last updated: Aug 2, 2025

Count Prefix and Suffix Pairs 1

January 8, 2025 · 3 min · array · hash-function · leetcode · rolling-hash · string · string-matching · trie · video · Last updated: Jul 29, 2025

Design a Sparse Array

January 7, 2025 · 3 min · daily-coding-problem · Last updated: Aug 2, 2025

String Matching in an Array

January 7, 2025 · 2 min · array · leetcode · string · string-matching · video · Last updated: Aug 2, 2025

Minimum Number of Operations to Move All Balls to Each Box

January 6, 2025 · 4 min · array · leetcode · prefix-sum · string · video · Last updated: Aug 2, 2025

Design hit counter with range queries

January 5, 2025 · 3 min · daily-coding-problem · Last updated: Aug 2, 2025

Square root of a real number

January 5, 2025 · 3 min · daily-coding-problem · Last updated: Jul 31, 2025

Shifting Letters II

January 5, 2025 · 4 min · array · leetcode · prefix-sum · string · Last updated: Aug 2, 2025

Check if target word exists in matrix horizontally or vertically

January 5, 2025 · 4 min · daily-coding-problem · Last updated: Aug 2, 2025

Break a string into lines of length k without breaking words

January 5, 2025 · 4 min · daily-coding-problem · Last updated: Aug 2, 2025

Expected number of rounds to reach one remaining coin

January 4, 2025 · 2 min · daily-coding-problem · Last updated: Jul 31, 2025

Maximum coins from top-left to bottom-right with right or down moves

January 4, 2025 · 4 min · daily-coding-problem · Last updated: Aug 2, 2025

Smallest set to cover all intervals

January 4, 2025 · 4 min · daily-coding-problem · greedy · Last updated: Aug 2, 2025

Number of Ways to Split Array

January 3, 2025 · 4 min · array · leetcode · prefix-sum · video · Last updated: Aug 2, 2025

Generate a finite, but an arbitrarily large binary tree in O(1) time

January 2, 2025 · 4 min · daily-coding-problem · randomized · randomized-algo · Last updated: Aug 2, 2025

Find all starting indices of anagrams of a word in a string

January 2, 2025 · 3 min · daily-coding-problem · Last updated: Aug 2, 2025

Count Vowel Strings in Ranges

January 2, 2025 · 5 min · array · leetcode · prefix-sum · string · video · Last updated: Aug 2, 2025

2024 ²⁴²¹

December ¹⁰⁴

Best Sightseeing Pair

December 27, 2024 · 3 min · array · dynamic-programming · kadane · leetcode · Last updated: Aug 2, 2025

Find Largest Value in Each Tree Row

December 25, 2024 · 3 min · binary-tree · breadth-first-search · depth-first-search · leetcode · traversal/level-order · tree · video · Last updated: Aug 2, 2025

Check if doubly linked list is palindrome

December 24, 2024 · 3 min · daily-coding-problem · two-pointers · doubly-linked-list · Last updated: Aug 2, 2025

Shortest substring containing all characters in a set

December 24, 2024 · 4 min · daily-coding-problem · sliding-window · Last updated: Aug 2, 2025

Return two prime numbers that sum to a given even number

December 24, 2024 · 3 min · daily-coding-problem · primality · Last updated: Jul 31, 2025

Find Minimum Diameter After Merging Two Trees

December 24, 2024 · 6 min · breadth-first-search · depth-first-search · graph · leetcode · tree · Last updated: Aug 2, 2025

Minimum Number of Operations to Sort a Binary Tree by Level

December 23, 2024 · 8 min · binary-tree · breadth-first-search · leetcode · mermaid · mermaid-hidden · traversal/level-order · tree · video · Last updated: Aug 2, 2025

Maximum Number of K-Divisible Components

December 21, 2024 · 6 min · depth-first-search · leetcode · mermaid · mermaid-connect-subgraph · tree · Last updated: Aug 2, 2025

Reverse Odd Levels of Binary Tree

December 20, 2024 · 4 min · alternate · binary-tree · breadth-first-search · depth-first-search · leetcode · reverse · traversal/level-order · tree · video · Last updated: Aug 2, 2025

Final Prices With a Special Discount in a Shop

December 18, 2024 · 7 min · array · leetcode · monotonic-stack · stack · video · Last updated: Jun 28, 2025

Construct String With Repeat Limit

December 17, 2024 · 4 min · counting · greedy · hash-table · heap-priority-queue · leetcode · string · video · Last updated: Aug 2, 2025

Final Array State After K Multiplication Operations 1

December 16, 2024 · 5 min · array · heap-priority-queue · leetcode · math · simulation · video · Last updated: Aug 2, 2025

Maximum Average Pass Ratio

December 15, 2024 · 4 min · array · greedy · heap-priority-queue · leetcode · Last updated: Jun 28, 2025

Continuous Subarrays

December 14, 2024 · 5 min · array · heap-priority-queue · leetcode · monotonic-queue · ordered-set · queue · sliding-window · Last updated: Aug 2, 2025

Find Score of an Array After Marking All Elements

December 13, 2024 · 6 min · array · hash-table · heap-priority-queue · leetcode · simulation · sorting · video · Last updated: Aug 2, 2025

Take Gifts From the Richest Pile

December 12, 2024 · 3 min · array · heap-priority-queue · leetcode · simulation · video · Last updated: Aug 2, 2025

Maximum Beauty of an Array After Applying Operation

December 11, 2024 · 8 min · array · binary-search · leetcode · sliding-window · sorting · Last updated: Aug 2, 2025

Find Longest Special Substring That Occurs Thrice 2

December 10, 2024 · 2 min · binary-search · counting · hash-table · leetcode · sliding-window · string · todo · Last updated: Aug 2, 2025

Find Longest Special Substring That Occurs Thrice 1

December 10, 2024 · 10 min · binary-search · counting · hash-table · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Special Array 2

December 9, 2024 · 4 min · array · binary-search · leetcode · prefix-sum · video · Last updated: Aug 2, 2025

Minimum Limit of Balls in a Bag

December 7, 2024 · 4 min · array · binary-search · leetcode · Last updated: Jun 28, 2025

Maximum Number of Integers to Choose From a Range I

December 6, 2024 · 3 min · array · binary-search · greedy · hash-table · leetcode · sorting · video · Last updated: Aug 2, 2025

Move Pieces to Obtain a String

December 4, 2024 · 5 min · leetcode · string · two-pointers · video · Last updated: Aug 2, 2025

Alien Dictionary

December 2, 2024 · 5 min · array · breadth-first-search · depth-first-search · graph · leetcode · string · topological-sort · Last updated: Aug 3, 2025

Amount of New Area Painted Each Day

December 2, 2024 · 9 min · array · backtracking · bit-manipulation · bitmask · breadth-first-search · counting · database · design · dynamic-programming · enumeration · greedy · hash-function · hash-table · heap-priority-queue · leetcode · math · matrix · ordered-set · prefix-sum · rolling-hash · segment-tree · simulation · sorting · string · todo · two-pointers · Last updated: Aug 2, 2025

Binary Tree Pruning

December 2, 2024 · 3 min · binary-tree · bt-binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Brace Expansion

December 2, 2024 · 4 min · array · backtracking · breadth-first-search · combination · counting · greedy · hash-table · leetcode · math · permutation-combination · sorting · string · two-pointers · Last updated: Aug 2, 2025

Check if an element exists in a binary tree

December 2, 2024 · 6 min · search · bt-binary-tree · Last updated: Aug 2, 2025

Check if postordered array forms a binary search tree

December 2, 2024 · 4 min · array-algo · bst-binary-search-tree · traversal · traversal/postorder · Last updated: Aug 2, 2025

Construct Binary Search Tree BST from Preorder Traversal

December 2, 2024 · 5 min · array · binary-search-tree · binary-tree · bst-binary-search-tree · leetcode · monotonic-stack · stack · tree · Last updated: Aug 2, 2025

Construct reverse sum hierarchy triangle from an array

December 2, 2024 · 5 min · array · array-algo · Last updated: Aug 2, 2025

Convert a sorted doubly linked list DLL to balanced binary search tree

December 2, 2024 · 3 min · convert · bt-binary-tree · doubly-linked-list · Last updated: Aug 2, 2025

Convert a sorted doubly linked list DLL to balanced binary search tree in-place

December 2, 2024 · 3 min · convert · bt-binary-tree · doubly-linked-list · Last updated: Aug 2, 2025

Convert Binary Tree into Threaded Binary Tree

December 2, 2024 · 6 min · convert · bt-binary-tree · threaded-binary-tree · mermaid-threaded-binary-tree · Last updated: Aug 2, 2025

Count Good Nodes in Binary Tree

December 2, 2024 · 3 min · binary-tree · breadth-first-search · bt-binary-tree · depth-first-search · leetcode · tree · Last updated: Mar 16, 2025

Create Sorted Array through Instructions

December 2, 2024 · 4 min · array · binary-indexed-tree · binary-search · divide-and-conquer · leetcode · merge-sort · ordered-set · segment-tree · todo · Last updated: Aug 2, 2025

De Bruijn Sequence

December 2, 2024 · 14 min · daily-coding-problem · graph-theory · eulerian-path · backtracking · string-processing · Last updated: Aug 8, 2025

Delete in a Binary Search Tree

December 2, 2024 · 7 min · binary-search-tree · binary-tree · bst-binary-search-tree · delete_remove · leetcode · traversal/inorder · tree · Last updated: Aug 2, 2025

Delivering Boxes from Storage to Ports

December 2, 2024 · 6 min · array · dynamic-programming · heap-priority-queue · leetcode · math · monotonic-queue · prefix-sum · queue · segment-tree · simulation · todo · Last updated: Aug 2, 2025

Duplicate each node in a binary search tree and add as its left child

December 2, 2024 · 4 min · duplicates-algo · bst-binary-search-tree · Last updated: Aug 2, 2025

Evaluate an expression tree and generate a parenthesised form

December 2, 2024 · 4 min · expression-tree · bt-binary-tree · Last updated: Aug 2, 2025

Falling Squares

December 2, 2024 · 4 min · array · leetcode · ordered-set · segment-tree · todo · Last updated: Aug 2, 2025

Fancy Sequence

December 2, 2024 · 4 min · database · design · leetcode · math · segment-tree · todo · Last updated: Aug 2, 2025

Find a Corresponding Node of a Binary Tree in a Clone of That Tree

December 2, 2024 · 5 min · binary-tree · breadth-first-search · bt-binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Find a Value of a Mysterious Function Closest to Target

December 2, 2024 · 7 min · array · binary-search · bit-manipulation · depth-first-search · leetcode · segment-tree · todo · tree · Last updated: Jul 29, 2025

Find Bottom Left Tree Value

December 2, 2024 · 5 min · binary-tree · breadth-first-search · bt-binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Find Eventual Safe States

December 2, 2024 · 4 min · breadth-first-search · depth-first-search · graph · leetcode · topological-sort · Last updated: Aug 2, 2025

Find GCD of n numbers

December 2, 2024 · 3 min · numerical-algo · daily-coding-problem · Last updated: Jul 31, 2025

Find K Closest Elements

December 2, 2024 · 7 min · array · binary-search · coordinate-geometry · heap-priority-queue · leetcode · search/binary · sliding-window · sorting · two-pointers · Last updated: Aug 1, 2025

Find Leaves of Binary Tree

December 2, 2024 · 3 min · binary-tree · binary-tree-leaf · bt-binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Find nodes in binary tree without siblings

December 2, 2024 · 3 min · bt-binary-tree · Last updated: Aug 2, 2025

Find Size of Binary Tree

December 2, 2024 · 4 min · bst-binary-search-tree · Last updated: Aug 2, 2025

Find the depth of a node in a binary tree

December 2, 2024 · 3 min · bt-binary-tree · Last updated: Aug 2, 2025

Find the height of a node in a binary tree

December 2, 2024 · 4 min · bt-binary-tree · Last updated: Aug 2, 2025

Flatten binary tree to linked list in order of inorder traversal

December 2, 2024 · 9 min · convert · bt-binary-tree · Last updated: Aug 2, 2025

Given preorder traversal of a BST, check if each non-leaf node has only one child

December 2, 2024 · 4 min · bst-binary-search-tree · traversal · traversal/preorder · Last updated: Aug 2, 2025

Implement circular linked list

December 2, 2024 · 6 min · linkedlist · implementation · circular · Last updated: Aug 2, 2025

Implement Hierarchical Locking System for Tree Structures

December 2, 2024 · 6 min · array · bit-manipulation · bitmask · breadth-first-search · depth-first-search · design · dynamic-programming · enumeration · hash-table · leetcode · math · tree · tree-ds · Last updated: Aug 2, 2025

Implement queue using linked list

December 2, 2024 · 3 min · stack · queue · linkedlist · Last updated: Aug 2, 2025

Implementing a queue using a fixed-size array

December 2, 2024 · 10 min · queue · generics · Last updated: Aug 10, 2025

Insert into a Binary Search Tree

December 2, 2024 · 4 min · binary-search-tree · binary-tree · bst-binary-search-tree · leetcode · tree · Last updated: Aug 2, 2025

Interval Scheduling Problem

December 2, 2024 · 3 min · greedy · schedule · interval · Last updated: Jul 24, 2025

K closest Points to Origin

December 2, 2024 · 7 min · array · coordinate-geometry · divide-and-conquer · geometry · heap · heap-priority-queue · leetcode · math · maths · quickselect · sorting · Last updated: Aug 2, 2025

Largest Divisible Subset

December 2, 2024 · 6 min · array · dynamic-programming · leetcode · math · numerical-algo · sorting · Last updated: Aug 2, 2025

Left side view of a tree

December 2, 2024 · 3 min · n-ary-tree · Last updated: Aug 2, 2025

Longest Substring of One Repeating Character

December 2, 2024 · 4 min · array · leetcode · ordered-set · segment-tree · string · todo · Last updated: Aug 2, 2025

Longest Substring with Same Letters after Replacement

December 2, 2024 · 4 min · hash-table · leetcode · sliding-window · string · video · Last updated: Aug 1, 2025

Maximum Binary Tree

December 2, 2024 · 6 min · array · binary-tree · divide-and-conquer · leetcode · monotonic-stack · stack · stack/monotonic · tree · Last updated: Aug 2, 2025

Maximum in a Binary Search Tree

December 2, 2024 · 3 min · bst-binary-search-tree · Last updated: Aug 2, 2025

Maximum in a Binary Tree

December 2, 2024 · 3 min · bt-binary-tree · max-min · Last updated: Aug 2, 2025

Min Queue

December 2, 2024 · 6 min · stack · queue · max-min · Last updated: Aug 2, 2025

Minimum in a Binary Search Tree

December 2, 2024 · 3 min · bst-binary-search-tree · Last updated: Aug 2, 2025

Minimum Possible Integer After at Most K Adjacent Swaps On Digits

December 2, 2024 · 3 min · binary-indexed-tree · bit-manipulation · depth-first-search · greedy · hash-table · leetcode · segment-tree · string · todo · tree · Last updated: Aug 2, 2025

My Calendar 3

December 2, 2024 · 3 min · binary-search · design · leetcode · ordered-set · prefix-sum · segment-tree · todo · Last updated: Aug 2, 2025

Nodes at Distance k from Leaf Nodes in Binary Tree

December 2, 2024 · 4 min · bt-binary-tree · binary-tree-leaf · Last updated: Aug 2, 2025

Nodes at Distance k from root in Binary Tree

December 2, 2024 · 3 min · bt-binary-tree · Last updated: Aug 2, 2025

Non-overlapping Intervals

December 2, 2024 · 3 min · array · daily-coding-problem · dynamic-programming · greedy · interval · leetcode · sorting · Last updated: Aug 2, 2025

Number of Connected Components in an Undirected Graph

December 2, 2024 · 5 min · breadth-first-search · component · connection · depth-first-search · disjoint-set · graph · graph/undirected · leetcode · matrix · union-find · Last updated: Aug 2, 2025

Number of elements smaller than root in preorder traversal of a BST

December 2, 2024 · 5 min · bst-binary-search-tree · traversal · traversal/preorder · search/binary · Last updated: Aug 2, 2025

Pacific Atlantic Water Flow

December 2, 2024 · 7 min · array · bfs · breadth-first-search · depth-first-search · dfs · leetcode · matrix · Last updated: Aug 2, 2025

Palindromic Substrings

December 2, 2024 · 5 min · dynamic-programming · leetcode · palindrome · string · two-pointers · Last updated: Aug 7, 2025

Plus One 2 - Given number as Linked List plus one

December 2, 2024 · 5 min · leetcode · linked-list · linkedlist · math · numerical-algo · Last updated: Jul 31, 2025

Postorder Node Iterator of Binary Tree

December 2, 2024 · 7 min · bt-binary-tree · iterator · traversal · traversal/postorder · Last updated: Aug 2, 2025

Power of Three

December 2, 2024 · 7 min · leetcode · math · maths · recursion · Last updated: Aug 1, 2025

Print or return all leaf nodes of a binary tree

December 2, 2024 · 3 min · bt-binary-tree · binary-tree-leaf · Last updated: Aug 2, 2025

Print or return all the full nodes in a binary tree

December 2, 2024 · 4 min · bt-binary-tree · Last updated: Jun 4, 2025

Print or return ancestors of a given node in binary tree

December 2, 2024 · 4 min · bt-binary-tree · Last updated: Aug 2, 2025

Print or return nodes between two given levels in a binary tree

December 2, 2024 · 4 min · bt-binary-tree · traversal/level-order · Last updated: Aug 2, 2025

Pseudo-Palindromic Paths in a Binary Tree

December 2, 2024 · 5 min · binary-tree · bit-manipulation · breadth-first-search · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Range Sum Query - Immutable

December 2, 2024 · 2 min · array · design · leetcode · prefix-sum · segment-tree · Last updated: Aug 2, 2025

Rectangle Area 2

December 2, 2024 · 8 min · array · leetcode · line-sweep · ordered-set · segment-tree · todo · Last updated: Aug 2, 2025

Replace each node in BST with subtree sum and its value

December 2, 2024 · 7 min · bt-binary-tree · Last updated: Aug 2, 2025

Right side view of a tree

December 2, 2024 · 3 min · n-ary-tree · Last updated: Aug 2, 2025

Robot Bounded In Circle

December 2, 2024 · 7 min · leetcode · math · simulation · string · Last updated: Aug 1, 2025

Rotting Oranges

December 2, 2024 · 5 min · array · backtracking · bfs · bit-manipulation · bitmask · breadth-first-search · dynamic-programming · graph · hash-table · leetcode · math · matrix · prefix-sum · queue · sliding-window · Last updated: Aug 2, 2025

Shortest path in Binary Search Tree that adds up to a given value

December 2, 2024 · 5 min · todo · bst-binary-search-tree · shortest-path · Last updated: Aug 2, 2025

Strange Printer

December 2, 2024 · 17 min · dynamic-programming · leetcode · string · todo · Last updated: Aug 3, 2025

Sum of k smallest elements in BST

December 2, 2024 · 3 min · bst-binary-search-tree · traversal · sum · Last updated: Aug 2, 2025

Sum of Two Integers

December 2, 2024 · 1 min · bit-manipulation · bits · leetcode · math · sum · video · Last updated: Jul 31, 2025

Sum of two numbers using only bitwise operators

December 2, 2024 · 6 min · bits · video · Last updated: Jul 31, 2025

Task Scheduler

December 2, 2024 · 4 min · array · counting · greedy · hash-table · heap · heap-priority-queue · leetcode · sorting · Last updated: Aug 2, 2025

Top K Frequent Elements

December 2, 2024 · 5 min · array · bucket-sort · bucketsort · counting · divide-and-conquer · hash-table · heap-priority-queue · heap/min · kth · leetcode · quickselect · sorting · todo · topk · Last updated: Aug 16, 2025

Total sum excluding adjacent of a given node in BST

December 2, 2024 · 4 min · bst-binary-search-tree · adjacent · Last updated: Aug 2, 2025

Verify Preorder Serialization of a Binary Tree

December 2, 2024 · 7 min · binary-tree · bt-binary-tree · leetcode · stack · string · traversal/preorder · tree · Last updated: Aug 2, 2025

November ¹⁹⁹⁴

Accepted Candidates From the Interviews

November 29, 2024 · 4 min · database · leetcode · Last updated: Jun 28, 2025

Active Businesses

November 29, 2024 · 3 min · database · leetcode · Last updated: Jun 28, 2025

Add Bold Tag in String

November 29, 2024 · 6 min · array · hash-table · leetcode · string · string-matching · trie · Last updated: Jul 23, 2025

Add Two Integers

November 29, 2024 · 2 min · leetcode · math · Last updated: Jul 31, 2025

Add Two Polynomials Represented as Linked Lists

November 29, 2024 · 7 min · leetcode · linked-list · math · two-pointers · Last updated: Aug 2, 2025

Adding Spaces to a String

November 29, 2024 · 4 min · array · leetcode · simulation · string · two-pointers · Last updated: Aug 2, 2025

Alice and Bob Playing Flower Game

November 29, 2024 · 5 min · leetcode · math · Last updated: Jul 31, 2025

All People Report to the Given Manager

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Allow One Function Call

November 29, 2024 · 3 min · leetcode · Last updated: Aug 2, 2025

Apples & Oranges

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Apply Bitwise Operations to Make Strings Equal

November 29, 2024 · 3 min · bit-manipulation · leetcode · string · Last updated: Aug 2, 2025

Apply Discount Every n Orders

November 29, 2024 · 5 min · array · design · hash-table · leetcode · Last updated: Aug 2, 2025

Apply Discount to Prices

November 29, 2024 · 4 min · leetcode · string · Last updated: Aug 2, 2025

Apply Operations on Array to Maximize Sum of Squares

November 29, 2024 · 4 min · array · bit-manipulation · greedy · hash-table · leetcode · Last updated: Aug 2, 2025

Apply Operations to Make All Array Elements Equal to Zero

November 29, 2024 · 3 min · array · leetcode · prefix-sum · Last updated: Aug 2, 2025

Apply Operations to Make String Empty

November 29, 2024 · 3 min · array · counting · hash-table · leetcode · sorting · Last updated: Aug 2, 2025

Arrange Table by Gender

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Array Prototype ForEach

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Array Wrapper

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Available Captures for Rook

November 29, 2024 · 4 min · array · leetcode · matrix · simulation · Last updated: Jul 27, 2025

Average Height of Buildings in Each Segment

November 29, 2024 · 8 min · array · greedy · heap-priority-queue · leetcode · sorting · Last updated: Aug 2, 2025

Average Selling Price

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Average Time of Process per Machine

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Avoid Flood in The City

November 29, 2024 · 6 min · array · binary-search · greedy · hash-table · heap-priority-queue · leetcode · Last updated: Aug 2, 2025

Base 7

November 29, 2024 · 3 min · leetcode · math · Last updated: Aug 2, 2025

Beautiful Pairs

November 29, 2024 · 6 min · array · divide-and-conquer · geometry · leetcode · math · ordered-set · sorting · Last updated: Aug 2, 2025

Beautiful Towers II

November 29, 2024 · 5 min · array · leetcode · monotonic-stack · stack · Last updated: Aug 2, 2025

Before and After Puzzle

November 29, 2024 · 6 min · array · hash-table · leetcode · sorting · string · Last updated: Aug 2, 2025

Biggest Window Between Visits

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Binary Number with Alternating Bits

November 29, 2024 · 2 min · bit-manipulation · leetcode · Last updated: Aug 2, 2025

Binary Search Tree Iterator II

November 29, 2024 · 6 min · binary-search-tree · binary-tree · design · iterator · leetcode · stack · tree · Last updated: Aug 2, 2025

Bitwise OR of All Subsequence Sums

November 29, 2024 · 4 min · array · bit-manipulation · brainteaser · leetcode · math · Last updated: Aug 2, 2025

Bitwise User Permissions Analysis

November 29, 2024 · 2 min · database · leetcode · Last updated: Aug 2, 2025

Block Placement Queries

November 29, 2024 · 6 min · array · binary-indexed-tree · binary-search · leetcode · segment-tree · Last updated: Aug 2, 2025

Boundary of Binary Tree

November 29, 2024 · 8 min · binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Break a Palindrome

November 29, 2024 · 2 min · greedy · leetcode · string · Last updated: Aug 2, 2025

Bricks Falling When Hit

November 29, 2024 · 12 min · array · leetcode · matrix · union-find · Last updated: Aug 2, 2025

Brightest Position on Street

November 29, 2024 · 5 min · array · leetcode · ordered-set · prefix-sum · Last updated: Aug 2, 2025

Broken Calculator

November 29, 2024 · 3 min · greedy · leetcode · math · Last updated: Aug 2, 2025

Build Binary Expression Tree From Infix Expression

November 29, 2024 · 9 min · binary-tree · leetcode · stack · string · tree · Last updated: Aug 2, 2025

Build the Equation

November 29, 2024 · 4 min · database · leetcode · Last updated: Jul 26, 2025

Building H2O

November 29, 2024 · 5 min · concurrency · leetcode · Last updated: Aug 2, 2025

Buildings With an Ocean View

November 29, 2024 · 2 min · array · leetcode · monotonic-stack · stack · Last updated: Aug 2, 2025

Cache With Time Limit

November 29, 2024 · 5 min · leetcode · Last updated: Jul 1, 2025

Calculate Money in Leetcode Bank

November 29, 2024 · 4 min · leetcode · math · Last updated: Aug 2, 2025

Calculate Salaries

November 29, 2024 · 4 min · database · leetcode · Last updated: Jul 1, 2025

Calculate the Influence of Each Salesperson

November 29, 2024 · 3 min · database · leetcode · Last updated: Jul 1, 2025

Calculator with Method Chaining

November 29, 2024 · 4 min · leetcode · Last updated: Aug 2, 2025

Campus Bikes II

November 29, 2024 · 7 min · array · backtracking · bit-manipulation · bitmask · dynamic-programming · leetcode · Last updated: Jul 6, 2025

Can Convert String in K Moves

November 29, 2024 · 3 min · hash-table · leetcode · string · Last updated: Jul 1, 2025

Card Flipping Game

November 29, 2024 · 5 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

Categorize Box According to Criteria

November 29, 2024 · 3 min · leetcode · math · Last updated: Jul 1, 2025

Cells with Odd Values in a Matrix

November 29, 2024 · 3 min · array · leetcode · math · simulation · Last updated: Jul 6, 2025

Change Null Values in a Table to the Previous Value

November 29, 2024 · 3 min · database · leetcode · Last updated: Jul 1, 2025

Check If a String Is a Valid Sequence from Root to Leaves Path in a Binary Tree

November 29, 2024 · 4 min · binary-tree · breadth-first-search · depth-first-search · leetcode · tree · Last updated: Jul 3, 2025

Check if Binary String Has at Most One Segment of Ones

November 29, 2024 · 2 min · leetcode · string · Last updated: Jul 3, 2025

Check if Bitwise OR Has Trailing Zeros

November 29, 2024 · 4 min · array · bit-manipulation · leetcode · Last updated: Jul 6, 2025

Check if DFS Strings Are Palindromes

November 29, 2024 · 7 min · array · depth-first-search · hash-function · hash-table · leetcode · string · tree · Last updated: Jul 3, 2025

Check if Every Row and Column Contains All Numbers

November 29, 2024 · 4 min · array · hash-table · leetcode · matrix · Last updated: Jul 4, 2025

Check if Matrix Is X-Matrix

November 29, 2024 · 4 min · array · leetcode · matrix · Last updated: Jul 4, 2025

Check If N and Its Double Exist

November 29, 2024 · 4 min · array · binary-search · hash-table · leetcode · sorting · two-pointers · Last updated: Jul 6, 2025

Check If String Is Transformable With Substring Sort Operations

November 29, 2024 · 5 min · greedy · leetcode · sorting · string · Last updated: Jul 4, 2025

Check if Strings Can be Made Equal With Operations II

November 29, 2024 · 5 min · hash-table · leetcode · sorting · string · Last updated: Aug 2, 2025

Check if There is a Path With Equal Number of 0’s And 1’s

November 29, 2024 · 4 min · array · dynamic-programming · leetcode · matrix · Last updated: Jul 4, 2025

Check if There Is a Valid Parentheses String Path

November 29, 2024 · 7 min · array · dynamic-programming · leetcode · matrix · Last updated: Jul 4, 2025

Check if Two Chessboard Squares Have the Same Color

November 29, 2024 · 3 min · leetcode · math · string · Last updated: Jul 4, 2025

Check If Two Expression Trees are Equivalent

November 29, 2024 · 4 min · binary-tree · counting · depth-first-search · hash-table · leetcode · tree · Last updated: Aug 2, 2025

Check If Word Is Valid After Substitutions

November 29, 2024 · 4 min · leetcode · stack · string · Last updated: Jul 4, 2025

Check Knight Tour Configuration

November 29, 2024 · 6 min · array · breadth-first-search · depth-first-search · leetcode · matrix · simulation · Last updated: Jul 4, 2025

Checking Existence of Edge Length Limited Paths II

November 29, 2024 · 5 min · graph · leetcode · minimum-spanning-tree · union-find · Last updated: Jul 30, 2025

Choose Numbers From Two Arrays in Range

November 29, 2024 · 7 min · array · dynamic-programming · leetcode · Last updated: Jul 4, 2025

Chunk Array

November 29, 2024 · 2 min · leetcode · Last updated: Jul 4, 2025

Circle and Rectangle Overlapping

November 29, 2024 · 4 min · geometry · leetcode · math · Last updated: Aug 2, 2025

Class Performance

November 29, 2024 · 3 min · database · leetcode · Last updated: Jul 6, 2025

Classifying Triangles by Lengths

November 29, 2024 · 3 min · database · leetcode · Last updated: Jul 6, 2025

Clone Binary Tree With Random Pointer

November 29, 2024 · 5 min · binary-tree · breadth-first-search · depth-first-search · hash-table · leetcode · tree · Last updated: Jul 6, 2025

Closest Divisors

November 29, 2024 · 4 min · leetcode · math · Last updated: Jul 6, 2025

Closest Fair Integer

November 29, 2024 · 4 min · enumeration · leetcode · math · Last updated: Jul 6, 2025

Closest Leaf in a Binary Tree

November 29, 2024 · 5 min · binary-tree · breadth-first-search · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Closest Room

November 29, 2024 · 7 min · array · binary-search · leetcode · ordered-set · sorting · Last updated: Jul 6, 2025

Clumsy Factorial

November 29, 2024 · 5 min · leetcode · math · simulation · stack · Last updated: Jul 6, 2025

Coin Path

November 29, 2024 · 7 min · array · dynamic-programming · leetcode · Last updated: Jul 7, 2025

Collect Coins in a Tree

November 29, 2024 · 8 min · array · graph · leetcode · topological-sort · tree · Last updated: Jul 7, 2025

Collecting Chocolates

November 29, 2024 · 5 min · array · enumeration · leetcode · Last updated: Jul 7, 2025

Compute the Rank as a Percentage

November 29, 2024 · 4 min · database · leetcode · Last updated: Jul 7, 2025

Confusing Number II

November 29, 2024 · 7 min · backtracking · leetcode · math · Last updated: Jul 7, 2025

Consecutive Available Seats II

November 29, 2024 · 3 min · database · leetcode · Last updated: Jul 7, 2025

Construct Product Matrix

November 29, 2024 · 6 min · array · leetcode · matrix · prefix-sum · Last updated: Jul 7, 2025

Construct Smallest Number From DI String

November 29, 2024 · 6 min · backtracking · greedy · leetcode · stack · string · video · Last updated: Aug 2, 2025

Construct String with Minimum Cost

November 29, 2024 · 9 min · array · dynamic-programming · leetcode · string · suffix-array · Last updated: Jul 7, 2025

Construct the Longest New String

November 29, 2024 · 4 min · brainteaser · dynamic-programming · greedy · leetcode · math · Last updated: Jul 7, 2025

Construct the Minimum Bitwise Array I

November 29, 2024 · 5 min · array · bit-manipulation · leetcode · Last updated: Jul 7, 2025

Construct the Minimum Bitwise Array II

November 29, 2024 · 5 min · array · bit-manipulation · leetcode · Last updated: Aug 2, 2025

Contain Virus

November 29, 2024 · 6 min · array · breadth-first-search · depth-first-search · leetcode · matrix · simulation · Last updated: Jul 7, 2025

Convert an Array Into a 2D Array With Conditions

November 29, 2024 · 4 min · array · hash-table · leetcode · Last updated: Jul 7, 2025

Convert Callback Based Function to Promise Based Function

November 29, 2024 · 4 min · leetcode · Last updated: Jul 7, 2025

Convert Date Format

November 29, 2024 · 2 min · database · leetcode · Last updated: Jul 7, 2025

Convert Doubly Linked List to Array I

November 29, 2024 · 3 min · array · doubly-linked-list · leetcode · linked-list · Last updated: Jul 7, 2025

Convert Doubly Linked List to Array II

November 29, 2024 · 3 min · array · doubly-linked-list · leetcode · linked-list · Last updated: Jul 7, 2025

Convert JSON String to Object

November 29, 2024 · 5 min · leetcode · Last updated: Aug 2, 2025

Convert Object to JSON String

November 29, 2024 · 3 min · leetcode · Last updated: Aug 11, 2025

Convert the Temperature

November 29, 2024 · 2 min · leetcode · math · Last updated: Aug 2, 2025

Convert to Base -2

November 29, 2024 · 4 min · leetcode · math · Last updated: Aug 2, 2025

Correct a Binary Tree

November 29, 2024 · 7 min · binary-tree · breadth-first-search · depth-first-search · hash-table · leetcode · tree · Last updated: Aug 7, 2025

Count Almost Equal Pairs II

November 29, 2024 · 8 min · array · counting · enumeration · hash-table · leetcode · sorting · Last updated: Aug 2, 2025

Count Anagrams

November 29, 2024 · 8 min · combinatorics · counting · hash-table · leetcode · math · string · Last updated: Aug 2, 2025

Count Artifacts That Can Be Extracted

November 29, 2024 · 6 min · array · hash-table · leetcode · simulation · Last updated: Aug 2, 2025

Count Collisions on a Road

November 29, 2024 · 5 min · leetcode · simulation · stack · string · Last updated: Aug 2, 2025

Count Common Words With One Occurrence

November 29, 2024 · 4 min · array · counting · hash-table · leetcode · string · Last updated: Aug 2, 2025

Count Complete Substrings

November 29, 2024 · 9 min · hash-table · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Count Good Numbers

November 29, 2024 · 4 min · leetcode · math · recursion · Last updated: Jul 31, 2025

Count Houses in a Circular Street II

November 29, 2024 · 4 min · leetcode · Last updated: Aug 2, 2025

Count Lattice Points Inside a Circle

November 29, 2024 · 5 min · array · enumeration · geometry · hash-table · leetcode · math · Last updated: Aug 2, 2025

Count Nodes With the Highest Score

November 29, 2024 · 7 min · array · binary-tree · depth-first-search · leetcode · tree · Last updated: Jul 26, 2025

Count Number of Distinct Integers After Reverse Operations

November 29, 2024 · 4 min · array · counting · hash-table · leetcode · math · Last updated: Jul 26, 2025

Count Number of Rectangles Containing Each Point

November 29, 2024 · 6 min · array · binary-indexed-tree · binary-search · leetcode · sorting · Last updated: Jul 27, 2025

Count of Integers

November 29, 2024 · 9 min · dynamic-programming · leetcode · math · string · Last updated: Jul 27, 2025

Count of Substrings Containing Every Vowel and K Consonants 1

November 29, 2024 · 4 min · hash-table · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Count Pairs in Two Arrays

November 29, 2024 · 5 min · array · binary-search · leetcode · sorting · two-pointers · Last updated: Jul 26, 2025

Count Pairs Of Similar Strings

November 29, 2024 · 5 min · array · bit-manipulation · counting · hash-table · leetcode · string · Last updated: Aug 2, 2025

Count Pairs Whose Sum is Less than Target

November 29, 2024 · 5 min · array · binary-search · leetcode · sorting · two-pointers · Last updated: Aug 2, 2025

Count Pairs With XOR in a Range

November 29, 2024 · 9 min · array · bit-manipulation · leetcode · trie · Last updated: Aug 2, 2025

Count Palindromic Subsequences

November 29, 2024 · 7 min · dynamic-programming · leetcode · string · Last updated: Aug 2, 2025

Count Prefixes of a Given String

November 29, 2024 · 3 min · array · leetcode · string · Last updated: Aug 2, 2025

Count Special Integers

November 29, 2024 · 3 min · dynamic-programming · leetcode · math · Last updated: Aug 2, 2025

Count Square Sum Triples

November 29, 2024 · 2 min · enumeration · leetcode · math · Last updated: Aug 2, 2025

Count Student Number in Departments

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Count Subarrays Where Max Element Appears at Least K Times

November 29, 2024 · 3 min · array · leetcode · sliding-window · Last updated: Aug 2, 2025

Count Subarrays With More Ones Than Zeros

November 29, 2024 · 4 min · array · binary-indexed-tree · binary-search · divide-and-conquer · leetcode · merge-sort · ordered-set · segment-tree · Last updated: Aug 2, 2025

Count Submatrices With All Ones

November 29, 2024 · 7 min · array · dynamic-programming · leetcode · matrix · monotonic-stack · stack · Last updated: Aug 2, 2025

Count Submatrices With Equal Frequency of X and Y

November 29, 2024 · 8 min · array · leetcode · matrix · prefix-sum · Last updated: Aug 2, 2025

Count Submatrices with Top-Left Element and Sum Less Than k

November 29, 2024 · 4 min · array · leetcode · matrix · prefix-sum · Last updated: Aug 2, 2025

Count Substrings That Can Be Rearranged to Contain a String I

November 29, 2024 · 6 min · hash-table · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Count Substrings That Can Be Rearranged to Contain a String II

November 29, 2024 · 7 min · hash-table · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Count Substrings That Satisfy K-Constraint II

November 29, 2024 · 9 min · array · binary-search · leetcode · prefix-sum · sliding-window · string · Last updated: Aug 2, 2025

Count Substrings With K-Frequency Characters I

November 29, 2024 · 4 min · hash-table · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Count Substrings with Only One Distinct Letter

November 29, 2024 · 4 min · leetcode · math · string · Last updated: Aug 2, 2025

Count Tested Devices After Test Operations

November 29, 2024 · 5 min · array · counting · leetcode · simulation · Last updated: Aug 2, 2025

Count the Digits That Divide a Number

November 29, 2024 · 3 min · leetcode · math · Last updated: Aug 2, 2025

Count the Number of Beautiful Subarrays

November 29, 2024 · 5 min · array · bit-manipulation · hash-table · leetcode · prefix-sum · Last updated: Aug 2, 2025

Count the Number of Experiments

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Count the Number of Good Nodes

November 29, 2024 · 6 min · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Count the Number of Good Partitions

November 29, 2024 · 5 min · array · combinatorics · hash-table · leetcode · math · Last updated: Aug 2, 2025

Count the Number of Good Subsequences

November 29, 2024 · 4 min · combinatorics · counting · hash-table · leetcode · math · string · Last updated: Aug 2, 2025

Count the Number of Houses at a Certain Distance I

November 29, 2024 · 6 min · breadth-first-search · graph · leetcode · prefix-sum · Last updated: Aug 2, 2025

Count the Number of Incremovable Subarrays II

November 29, 2024 · 4 min · array · binary-search · leetcode · two-pointers · Last updated: Aug 2, 2025

Count the Number of Infection Sequences

November 29, 2024 · 3 min · array · combinatorics · leetcode · math · Last updated: Aug 2, 2025

Count the Number of Inversions

November 29, 2024 · 7 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Count the Number of K-Big Indices

November 29, 2024 · 4 min · array · binary-indexed-tree · binary-search · divide-and-conquer · leetcode · merge-sort · ordered-set · segment-tree · Last updated: Aug 2, 2025

Count the Number of K-Free Subsets

November 29, 2024 · 6 min · array · combinatorics · dynamic-programming · leetcode · math · sorting · Last updated: Aug 2, 2025

Count the Number of Powerful Integers

November 29, 2024 · 5 min · dynamic-programming · leetcode · math · string · Last updated: Aug 2, 2025

Count the Number of Vowel Strings in Range

November 29, 2024 · 4 min · array · counting · leetcode · string · Last updated: Aug 2, 2025

Count Triplets with Even XOR Set Bits I

November 29, 2024 · 6 min · array · bit-manipulation · leetcode · Last updated: Aug 2, 2025

Count Triplets with Even XOR Set Bits II

November 29, 2024 · 6 min · array · bit-manipulation · leetcode · Last updated: Aug 2, 2025

Count Valid Paths in a Tree

November 29, 2024 · 10 min · depth-first-search · dynamic-programming · leetcode · math · number-theory · tree · Last updated: Aug 2, 2025

Count Ways to Build Rooms in an Ant Colony

November 29, 2024 · 9 min · combinatorics · dynamic-programming · graph · leetcode · math · topological-sort · tree · Last updated: Aug 2, 2025

Count Ways to Distribute Candies

November 29, 2024 · 5 min · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Count Ways to Group Overlapping Ranges

November 29, 2024 · 6 min · array · leetcode · sorting · Last updated: Aug 2, 2025

Count Ways to Make Array With Product

November 29, 2024 · 11 min · array · combinatorics · dynamic-programming · leetcode · math · number-theory · Last updated: Aug 2, 2025

Create a Session Bar Chart

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Create Components With Same Value

November 29, 2024 · 9 min · array · depth-first-search · enumeration · leetcode · math · tree · Last updated: Aug 2, 2025

Create Object from Two Arrays

November 29, 2024 · 3 min · leetcode · Last updated: Aug 2, 2025

Create Target Array in the Given Order

November 29, 2024 · 3 min · array · leetcode · simulation · Last updated: Aug 2, 2025

Curry

November 29, 2024 · 3 min · leetcode · Last updated: Aug 2, 2025

Customer Purchasing Behavior Analysis

November 29, 2024 · 6 min · database · leetcode · Last updated: Aug 2, 2025

Customer Who Visited but Did Not Make Any Transactions

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Customers Who Bought All Products

November 29, 2024 · 2 min · database · leetcode · Last updated: Jul 6, 2025

Customers Who Bought Products A and B but Not C

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Cut Off Trees for Golf Event

November 29, 2024 · 12 min · array · breadth-first-search · heap-priority-queue · leetcode · matrix · Last updated: Aug 2, 2025

Cycle Length Queries in a Tree

November 29, 2024 · 6 min · array · binary-tree · leetcode · tree · Last updated: Aug 2, 2025

Date Range Generator

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Debounce

November 29, 2024 · 4 min · daily-coding-problem · leetcode · Last updated: Jan 1, 2025

Decode the Slanted Ciphertext

November 29, 2024 · 6 min · leetcode · simulation · string · Last updated: Aug 2, 2025

Decode XORed Array

November 29, 2024 · 3 min · array · bit-manipulation · leetcode · Last updated: Aug 2, 2025

Decode XORed Permutation

November 29, 2024 · 5 min · array · bit-manipulation · leetcode · Last updated: Aug 2, 2025

Decremental String Concatenation

November 29, 2024 · 7 min · array · dynamic-programming · leetcode · string · Last updated: Aug 2, 2025

Delay the Resolution of Each Promise

November 29, 2024 · 3 min · leetcode · Last updated: Aug 2, 2025

Delete Greatest Value in Each Row

November 29, 2024 · 5 min · array · heap-priority-queue · leetcode · matrix · simulation · sorting · Last updated: Aug 2, 2025

Delete Tree Nodes

November 29, 2024 · 5 min · array · breadth-first-search · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Depth of BST Given Insertion Order

November 29, 2024 · 6 min · array · binary-search-tree · binary-tree · leetcode · ordered-set · tree · Last updated: Aug 2, 2025

Design a File Sharing System

November 29, 2024 · 8 min · data-stream · design · hash-table · heap-priority-queue · leetcode · sorting · Last updated: Aug 2, 2025

Design a Food Rating System

November 29, 2024 · 6 min · design · hash-table · heap-priority-queue · leetcode · ordered-set · Last updated: Aug 2, 2025

Design a Todo List

November 29, 2024 · 6 min · array · design · hash-table · leetcode · sorting · string · Last updated: Aug 2, 2025

Design an ATM Machine

November 29, 2024 · 6 min · array · design · greedy · leetcode · Last updated: Aug 2, 2025

Design an Ordered Stream

November 29, 2024 · 3 min · array · data-stream · design · hash-table · leetcode · Last updated: Aug 2, 2025

Design Cancellable Function

November 29, 2024 · 6 min · leetcode · Last updated: Aug 2, 2025

Design Excel Sum Formula

November 29, 2024 · 12 min · array · design · graph · leetcode · matrix · topological-sort · Last updated: Aug 2, 2025

Design Front Middle Back Queue

November 29, 2024 · 10 min · array · data-stream · design · leetcode · linked-list · queue · Last updated: Aug 2, 2025

Design Log Storage System

November 29, 2024 · 6 min · design · hash-table · leetcode · ordered-set · string · Last updated: Aug 2, 2025

Design Parking System

November 29, 2024 · 4 min · counting · design · leetcode · simulation · Last updated: Aug 2, 2025

Destination City

November 29, 2024 · 3 min · array · hash-table · leetcode · string · Last updated: Aug 2, 2025

Destroy Sequential Targets

November 29, 2024 · 6 min · array · counting · hash-table · leetcode · Last updated: Aug 2, 2025

Detect Cycles in 2D Grid

November 29, 2024 · 8 min · array · breadth-first-search · depth-first-search · leetcode · matrix · union-find · Last updated: Aug 2, 2025

Determine Color of a Chessboard Square

November 29, 2024 · 3 min · leetcode · math · string · Last updated: Aug 2, 2025

Determine if String Halves Are Alike

November 29, 2024 · 4 min · counting · leetcode · string · Last updated: Aug 2, 2025

Determine if Two Events Have Conflict

November 29, 2024 · 4 min · array · leetcode · string · Last updated: Aug 2, 2025

Determine the Minimum Sum of a k-avoiding Array

November 29, 2024 · 4 min · greedy · leetcode · math · Last updated: Aug 2, 2025

DI String Match

November 29, 2024 · 4 min · array · greedy · leetcode · string · two-pointers · Last updated: Aug 2, 2025

Difference Between Maximum and Minimum Price Sum

November 29, 2024 · 13 min · array · depth-first-search · dynamic-programming · leetcode · tree · Last updated: Aug 2, 2025

Difference Between Ones and Zeros in Row and Column

November 29, 2024 · 7 min · array · leetcode · matrix · simulation · Last updated: Aug 2, 2025

Dinner Plate Stacks

November 29, 2024 · 10 min · design · hash-table · heap-priority-queue · leetcode · stack · Last updated: Aug 2, 2025

Disconnect Path in a Binary Matrix by at Most One Flip

November 29, 2024 · 5 min · array · breadth-first-search · depth-first-search · dynamic-programming · leetcode · matrix · Last updated: Aug 2, 2025

Display Table of Food Orders in a Restaurant

November 29, 2024 · 6 min · array · hash-table · leetcode · ordered-set · sorting · string · Last updated: Aug 2, 2025

Display the First Three Rows

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Distance to a Cycle in Undirected Graph

November 29, 2024 · 11 min · breadth-first-search · depth-first-search · graph · leetcode · union-find · Last updated: Aug 2, 2025

Distinct Echo Substrings

November 29, 2024 · 4 min · hash-function · leetcode · rolling-hash · string · trie · Last updated: Aug 2, 2025

Distinct Numbers in Each Subarray

November 29, 2024 · 5 min · array · hash-table · leetcode · sliding-window · Last updated: Aug 2, 2025

Distribute Money to Maximum Children

November 29, 2024 · 6 min · greedy · leetcode · math · Last updated: Aug 2, 2025

Divide an Array Into Subarrays With Minimum Cost I

November 29, 2024 · 4 min · array · enumeration · leetcode · sorting · Last updated: Aug 2, 2025

Divide an Array Into Subarrays With Minimum Cost II

November 29, 2024 · 9 min · array · hash-table · heap-priority-queue · leetcode · sliding-window · Last updated: Aug 2, 2025

Divide Array Into Increasing Sequences

November 29, 2024 · 4 min · array · counting · leetcode · Last updated: Aug 2, 2025

Double Modular Exponentiation

November 29, 2024 · 5 min · array · leetcode · math · simulation · Last updated: Aug 2, 2025

Duplicate Zeros

November 29, 2024 · 5 min · array · leetcode · two-pointers · Last updated: Aug 2, 2025

Dynamic Pivoting of a Table

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Earliest Second to Mark Indices I

November 29, 2024 · 9 min · array · binary-search · leetcode · Last updated: Aug 2, 2025

Egg Drop With 2 Eggs and N Floors

November 29, 2024 · 4 min · dynamic-programming · leetcode · math · Last updated: Aug 2, 2025

Employees With Deductions

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Equal Sum Arrays With Minimum Number of Operations

November 29, 2024 · 6 min · array · counting · greedy · hash-table · leetcode · Last updated: Aug 2, 2025

Equal Tree Partition

November 29, 2024 · 3 min · binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Erect the Fence II

November 29, 2024 · 3 min · array · geometry · leetcode · math · Last updated: Aug 2, 2025

Escape the Spreading Fire

November 29, 2024 · 5 min · array · binary-search · breadth-first-search · leetcode · matrix · Last updated: Aug 2, 2025

Evaluate Boolean Expression

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Evaluate the Bracket Pairs of a String

November 29, 2024 · 6 min · array · hash-table · leetcode · string · Last updated: Aug 2, 2025

Even Odd Tree

November 29, 2024 · 5 min · binary-tree · breadth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Event Emitter

November 29, 2024 · 5 min · leetcode · Last updated: Aug 2, 2025

Exam Room

November 29, 2024 · 6 min · design · heap-priority-queue · leetcode · ordered-set · Last updated: Aug 2, 2025

Execute Asynchronous Functions in Parallel

November 29, 2024 · 3 min · leetcode · Last updated: Aug 2, 2025

Execution of All Suffix Instructions Staying in a Grid

November 29, 2024 · 6 min · leetcode · simulation · string · Last updated: Aug 2, 2025

Expressive Words

November 29, 2024 · 8 min · array · leetcode · string · two-pointers · Last updated: Aug 2, 2025

Factorial Generator

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Fair Candy Swap

November 29, 2024 · 5 min · array · binary-search · hash-table · leetcode · sorting · Last updated: Aug 2, 2025

Faulty Keyboard

November 29, 2024 · 4 min · leetcode · simulation · string · Last updated: Aug 2, 2025

Fill Missing Data

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Final Value of Variable After Performing Operations

November 29, 2024 · 4 min · array · leetcode · simulation · string · Last updated: Aug 2, 2025

Find a Peak Element II

November 29, 2024 · 7 min · array · binary-search · leetcode · matrix · Last updated: Aug 2, 2025

Find All The Lonely Nodes

November 29, 2024 · 4 min · binary-tree · breadth-first-search · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Find All Unique Email Domains

November 29, 2024 · 2 min · database · leetcode · Last updated: Aug 2, 2025

Find Anagram Mappings

November 29, 2024 · 3 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

Find And Replace in String

November 29, 2024 · 6 min · array · hash-table · leetcode · sorting · string · Last updated: Aug 2, 2025

Find Array Given Subset Sums

November 29, 2024 · 8 min · array · divide-and-conquer · leetcode · Last updated: Aug 2, 2025

Find Building Where Alice and Bob Can Meet

November 29, 2024 · 6 min · array · binary-indexed-tree · binary-search · heap-priority-queue · leetcode · monotonic-stack · segment-tree · stack · Last updated: Aug 2, 2025

Find Bursty Behavior

November 29, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

Find Candidates for Data Scientist Position II

November 29, 2024 · 6 min · database · leetcode · Last updated: Aug 2, 2025

Find Champion I

November 29, 2024 · 5 min · array · leetcode · matrix · Last updated: Aug 2, 2025

Find Cities in Each State

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Find Cities in Each State II

November 29, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

Find Closest Number to Zero

November 29, 2024 · 4 min · array · leetcode · Last updated: Aug 2, 2025

Find Common Elements Between Two Arrays

November 29, 2024 · 4 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

Find Cutoff Score for Each School

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Find Edges in Shortest Paths

November 29, 2024 · 9 min · breadth-first-search · depth-first-search · graph · heap-priority-queue · leetcode · shortest-path · Last updated: Aug 2, 2025

Find Expensive Cities

November 29, 2024 · 3 min · database · leetcode · Last updated: Jul 26, 2025

Find Good Days to Rob the Bank

November 29, 2024 · 6 min · array · dynamic-programming · leetcode · prefix-sum · Last updated: Jul 26, 2025

Find Kth Largest XOR Coordinate Value

November 29, 2024 · 5 min · array · bit-manipulation · divide-and-conquer · heap-priority-queue · leetcode · matrix · prefix-sum · quickselect · sorting · Last updated: Aug 2, 2025

Find Latest Group of Size M

November 29, 2024 · 6 min · array · binary-search · hash-table · leetcode · simulation · Last updated: Aug 2, 2025

Find Longest Calls

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Find Lucky Integer in an Array

November 29, 2024 · 4 min · array · counting · hash-table · leetcode · Last updated: Jul 5, 2025

Find Maximum Non-decreasing Array Length

November 29, 2024 · 4 min · array · binary-search · dynamic-programming · leetcode · monotonic-queue · monotonic-stack · queue · stack · Last updated: Aug 2, 2025

Find Maximum Removals From Source String

November 29, 2024 · 7 min · array · dynamic-programming · hash-table · leetcode · string · two-pointers · Last updated: Aug 2, 2025

Find Median Given Frequency of Numbers

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Find Minimum Time to Finish All Jobs II

November 29, 2024 · 4 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Find Mode in Binary Search Tree

November 29, 2024 · 6 min · binary-search-tree · binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Find N Unique Integers Sum up to Zero

November 29, 2024 · 3 min · array · leetcode · math · Last updated: Aug 2, 2025

Find Nearest Right Node in Binary Tree

November 29, 2024 · 5 min · binary-tree · breadth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Find Number of Coins to Place in Tree Nodes

November 29, 2024 · 8 min · depth-first-search · dynamic-programming · heap-priority-queue · leetcode · sorting · tree · Last updated: Aug 2, 2025

Find Overlapping Shifts

November 29, 2024 · 2 min · database · leetcode · Last updated: Aug 2, 2025

Find Peak Calling Hours for Each City

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Find Players With Zero or One Losses

November 29, 2024 · 5 min · array · counting · hash-table · leetcode · sorting · Last updated: Aug 2, 2025

Find Polygon With the Largest Perimeter

November 29, 2024 · 5 min · array · greedy · leetcode · prefix-sum · sorting · Last updated: Aug 2, 2025

Find Positive Integer Solution for a Given Equation

November 29, 2024 · 6 min · binary-search · interactive · leetcode · math · two-pointers · Last updated: Aug 2, 2025

Find Resultant Array After Removing Anagrams

November 29, 2024 · 5 min · array · hash-table · leetcode · sorting · string · Last updated: Aug 2, 2025

Find Shortest Path with K Hops

November 29, 2024 · 6 min · graph · heap-priority-queue · leetcode · shortest-path · Last updated: Jul 26, 2025

Find the Child Who Has the Ball After K Seconds

November 29, 2024 · 4 min · leetcode · math · simulation · Last updated: Aug 2, 2025

Find the Closest Marked Node

November 29, 2024 · 8 min · array · graph · heap-priority-queue · leetcode · shortest-path · Last updated: Aug 2, 2025

Find the Count of Monotonic Pairs I

November 29, 2024 · 7 min · array · combinatorics · dynamic-programming · leetcode · math · prefix-sum · Last updated: Aug 2, 2025

Find the Count of Monotonic Pairs II

November 29, 2024 · 8 min · array · combinatorics · dynamic-programming · leetcode · math · prefix-sum · Last updated: Aug 2, 2025

Find the Count of Numbers Which Are Not Special

November 29, 2024 · 6 min · array · leetcode · math · number-theory · Last updated: Aug 2, 2025

Find the Derangement of An Array

November 29, 2024 · 4 min · combinatorics · dynamic-programming · leetcode · math · Last updated: Aug 2, 2025

Find the Encrypted String

November 29, 2024 · 3 min · leetcode · string · Last updated: Aug 2, 2025

Find the Grid of Region Average

November 29, 2024 · 12 min · array · leetcode · matrix · Last updated: Aug 2, 2025

Find the Index of the Large Integer

November 29, 2024 · 8 min · array · binary-search · interactive · leetcode · Last updated: Aug 2, 2025

Find the Integer Added to Array II

November 29, 2024 · 6 min · array · enumeration · leetcode · sorting · two-pointers · Last updated: Aug 2, 2025

Find The K-th Lucky Number

November 29, 2024 · 3 min · bit-manipulation · leetcode · math · string · Last updated: Aug 2, 2025

Find the Key of the Numbers

November 29, 2024 · 4 min · leetcode · math · Last updated: Aug 2, 2025

Find the Kth Smallest Sum of a Matrix With Sorted Rows

November 29, 2024 · 5 min · array · binary-search · heap-priority-queue · leetcode · matrix · Last updated: Aug 2, 2025

Find the Last Marked Nodes in Tree

November 29, 2024 · 8 min · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Find the Lexicographically Smallest Valid Sequence

November 29, 2024 · 6 min · dynamic-programming · greedy · leetcode · string · two-pointers · Last updated: Aug 2, 2025

Find the Longest Equal Subarray

November 29, 2024 · 5 min · array · binary-search · hash-table · leetcode · sliding-window · Last updated: Aug 2, 2025

Find the Longest Semi-Repetitive Substring

November 29, 2024 · 4 min · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Find the Longest Valid Obstacle Course at Each Position

November 29, 2024 · 5 min · array · binary-indexed-tree · binary-search · leetcode · Last updated: Aug 2, 2025

Find the Losers of the Circular Game

November 29, 2024 · 5 min · array · hash-table · leetcode · simulation · Last updated: Aug 2, 2025

Find the Maximum Length of Valid Subsequence I

November 29, 2024 · 5 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Find the Maximum Length of Valid Subsequence II

November 29, 2024 · 5 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Find the Maximum Number of Elements in Subset

November 29, 2024 · 5 min · array · enumeration · hash-table · leetcode · Last updated: Aug 2, 2025

Find the Middle Index in Array

November 29, 2024 · 4 min · array · leetcode · prefix-sum · Last updated: Aug 2, 2025

Find the Minimum Area to Cover All Ones II

November 29, 2024 · 3 min · array · enumeration · leetcode · matrix · Last updated: Aug 2, 2025

Find the Minimum Cost Array Permutation

November 29, 2024 · 4 min · array · bit-manipulation · bitmask · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Find the Missing IDs

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Find the Number of Good Pairs I

November 29, 2024 · 4 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

Find the Number of Ways to Place People I

November 29, 2024 · 7 min · array · enumeration · geometry · leetcode · math · sorting · Last updated: Aug 2, 2025

Find the Number of Ways to Place People II

November 29, 2024 · 8 min · array · enumeration · geometry · leetcode · math · sorting · Last updated: Aug 2, 2025

Find the Number of Winning Players

November 29, 2024 · 5 min · array · counting · hash-table · leetcode · Last updated: Aug 2, 2025

Find the Original Typed String II

November 29, 2024 · 8 min · dynamic-programming · leetcode · prefix-sum · string · Last updated: Aug 2, 2025

Find the Quiet Students in All Exams

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Find the Sequence of Strings Appeared on the Screen

November 29, 2024 · 5 min · leetcode · simulation · string · Last updated: Aug 2, 2025

Find the String with LCP

November 29, 2024 · 9 min · array · dynamic-programming · greedy · leetcode · matrix · string · union-find · Last updated: Aug 2, 2025

Find the Subtasks That Did Not Execute

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Find the Sum of Encrypted Integers

November 29, 2024 · 4 min · array · leetcode · math · Last updated: Aug 2, 2025

Find Top Scoring Students II

November 29, 2024 · 7 min · database · leetcode · Last updated: Aug 2, 2025

Find Trending Hashtags II

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Find X-Sum of All K-Long Subarrays I

November 29, 2024 · 9 min · array · hash-table · heap-priority-queue · leetcode · sliding-window · Last updated: Aug 2, 2025

Finding MK Average

November 29, 2024 · 6 min · data-stream · design · heap-priority-queue · leetcode · ordered-set · queue · Last updated: Aug 2, 2025

Finding the Number of Visible Mountains

November 29, 2024 · 6 min · array · leetcode · monotonic-stack · sorting · stack · Last updated: Aug 2, 2025

First Letter Capitalization

November 29, 2024 · 4 min · database · leetcode · string · Last updated: Aug 2, 2025

First Unique Number

November 29, 2024 · 5 min · array · data-stream · design · hash-table · leetcode · queue · Last updated: Aug 2, 2025

Fizz Buzz Multithreaded

November 29, 2024 · 5 min · concurrency · leetcode · Last updated: Aug 2, 2025

Flatten Deeply Nested Array

November 29, 2024 · 4 min · leetcode · Last updated: Aug 2, 2025

Flip Binary Tree To Match Preorder Traversal

November 29, 2024 · 6 min · binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Flower Planting With No Adjacent

November 29, 2024 · 5 min · breadth-first-search · depth-first-search · graph · leetcode · Last updated: Aug 2, 2025

Form Smallest Number From Two Digit Arrays

November 29, 2024 · 4 min · array · enumeration · hash-table · leetcode · Last updated: Aug 2, 2025

Four Divisors

November 29, 2024 · 5 min · array · leetcode · math · Last updated: Aug 2, 2025

Frequency Tracker

November 29, 2024 · 6 min · design · hash-table · leetcode · Last updated: Aug 2, 2025

Friends With No Mutual Friends

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Furthest Point From Origin

November 29, 2024 · 4 min · counting · leetcode · string · Last updated: Aug 2, 2025

Game of Nim

November 29, 2024 · 4 min · array · bit-manipulation · brainteaser · dynamic-programming · game-theory · leetcode · math · Last updated: Aug 9, 2025

Game Play Analysis III

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

GCD Sort of an Array

November 29, 2024 · 8 min · array · leetcode · math · number-theory · sorting · union-find · Last updated: Aug 2, 2025

Generate Circular Array Values

November 29, 2024 · 3 min · leetcode · Last updated: Aug 2, 2025

Get Maximum in Generated Array

November 29, 2024 · 5 min · array · leetcode · simulation · Last updated: Aug 2, 2025

Get the Maximum Score

November 29, 2024 · 7 min · array · dynamic-programming · greedy · leetcode · two-pointers · Last updated: Aug 2, 2025

Get the Size of a DataFrame

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Global and Local Inversions

November 29, 2024 · 3 min · array · leetcode · math · Last updated: Aug 2, 2025

Goal Parser Interpretation

November 29, 2024 · 3 min · leetcode · string · Last updated: Aug 2, 2025

Goat Latin

November 29, 2024 · 4 min · leetcode · string · Last updated: Aug 2, 2025

Graph Connectivity With Threshold

November 29, 2024 · 7 min · array · leetcode · math · number-theory · union-find · Last updated: Aug 2, 2025

Grid Illumination

November 29, 2024 · 9 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

Group By

November 29, 2024 · 3 min · leetcode · Last updated: Aug 2, 2025

Group the People Given the Group Size They Belong To

November 29, 2024 · 4 min · array · greedy · hash-table · leetcode · Last updated: Aug 2, 2025

Happy Students

November 29, 2024 · 4 min · array · enumeration · leetcode · sorting · Last updated: Aug 2, 2025

Harshad Number

November 29, 2024 · 3 min · leetcode · math · Last updated: Aug 2, 2025

Hexspeak

November 29, 2024 · 5 min · leetcode · math · string · Last updated: Aug 2, 2025

High Five

November 29, 2024 · 5 min · array · hash-table · heap-priority-queue · leetcode · sorting · Last updated: Aug 2, 2025

High-Access Employees

November 29, 2024 · 6 min · array · hash-table · leetcode · sorting · string · Last updated: Jul 26, 2025

Highest Grade For Each Student

November 29, 2024 · 3 min · database · leetcode · Last updated: Jul 26, 2025

House Robber 4

November 29, 2024 · 5 min · array · binary-search · leetcode · Last updated: Aug 2, 2025

How Many Apples Can You Put into the Basket

November 29, 2024 · 3 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Immutability Helper

November 29, 2024 · 4 min · leetcode · Last updated: Aug 2, 2025

Implement Magic Dictionary

November 29, 2024 · 9 min · depth-first-search · design · hash-table · leetcode · string · trie · Last updated: Aug 2, 2025

Implement Trie II (Prefix Tree)

November 29, 2024 · 10 min · design · hash-table · leetcode · string · trie · Last updated: Aug 2, 2025

Increasing Order Search Tree

November 29, 2024 · 5 min · binary-search-tree · binary-tree · depth-first-search · leetcode · stack · tree · Last updated: Aug 2, 2025

Increment Submatrices by One

November 29, 2024 · 7 min · array · leetcode · matrix · prefix-sum · Last updated: Aug 2, 2025

Insert into a Sorted Circular Linked List

November 29, 2024 · 7 min · leetcode · linked-list · Last updated: Aug 2, 2025

Insufficient Nodes in Root to Leaf Paths

November 29, 2024 · 6 min · binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Intersection of Multiple Arrays

November 29, 2024 · 5 min · array · counting · hash-table · leetcode · sorting · Last updated: Aug 2, 2025

Intervals Between Identical Elements

November 29, 2024 · 6 min · array · hash-table · leetcode · prefix-sum · Last updated: Aug 2, 2025

Invalid Tweets II

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Inversion of Object

November 29, 2024 · 3 min · leetcode · Last updated: Aug 2, 2025

Investments in 2016

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Is Object Empty

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Jewels and Stones

November 29, 2024 · 3 min · hash-table · leetcode · string · Last updated: Aug 2, 2025

Jump Game 3

November 29, 2024 · 5 min · array · breadth-first-search · depth-first-search · leetcode · Last updated: Aug 2, 2025

K Highest Ranked Items Within a Price Range

November 29, 2024 · 11 min · array · breadth-first-search · heap-priority-queue · leetcode · matrix · sorting · Last updated: Aug 2, 2025

K Items With the Maximum Sum

November 29, 2024 · 4 min · greedy · leetcode · math · Last updated: Aug 2, 2025

K-diff Pairs in an Array

November 29, 2024 · 5 min · array · binary-search · hash-table · leetcode · sorting · two-pointers · Last updated: Aug 2, 2025

K-Similar Strings

November 29, 2024 · 6 min · breadth-first-search · leetcode · string · Last updated: Aug 2, 2025

K-th Nearest Obstacle Queries

November 29, 2024 · 5 min · array · heap-priority-queue · leetcode · Last updated: Aug 2, 2025

Keep Multiplying Found Values by Two

November 29, 2024 · 3 min · array · hash-table · leetcode · simulation · sorting · Last updated: Aug 2, 2025

Kth Smallest Amount With Single Denomination Combination

November 29, 2024 · 5 min · array · binary-search · bit-manipulation · combinatorics · leetcode · math · number-theory · Last updated: Aug 2, 2025

Kth Smallest Number in Multiplication Table

November 29, 2024 · 5 min · binary-search · leetcode · math · Last updated: Aug 2, 2025

Largest 3-Same-Digit Number in String

November 29, 2024 · 4 min · leetcode · string · Last updated: Aug 2, 2025

Largest Element in an Array after Merge Operations

November 29, 2024 · 4 min · array · greedy · leetcode · Last updated: Aug 2, 2025

Largest Magic Square

November 29, 2024 · 9 min · array · leetcode · matrix · prefix-sum · Last updated: Aug 2, 2025

Largest Number After Digit Swaps by Parity

November 29, 2024 · 5 min · heap-priority-queue · leetcode · sorting · Last updated: Aug 2, 2025

Largest Number After Mutating Substring

November 29, 2024 · 5 min · array · greedy · leetcode · string · Last updated: Aug 2, 2025

Largest Number At Least Twice of Others

November 29, 2024 · 4 min · array · leetcode · sorting · Last updated: Aug 2, 2025

Largest Subarray Length K

November 29, 2024 · 3 min · array · greedy · leetcode · Last updated: Aug 2, 2025

Largest Submatrix With Rearrangements

November 29, 2024 · 5 min · array · greedy · leetcode · matrix · sorting · Last updated: Aug 2, 2025

Largest Triangle Area

November 29, 2024 · 4 min · array · geometry · leetcode · math · Last updated: Aug 2, 2025

Largest Unique Number

November 29, 2024 · 3 min · array · hash-table · leetcode · sorting · Last updated: Aug 2, 2025

Largest Values From Labels

November 29, 2024 · 5 min · array · counting · greedy · hash-table · leetcode · sorting · Last updated: Aug 2, 2025

Last Day Where You Can Still Cross

November 29, 2024 · 10 min · array · binary-search · breadth-first-search · depth-first-search · leetcode · matrix · union-find · Last updated: Aug 2, 2025

Last Moment Before All Ants Fall Out of a Plank

November 29, 2024 · 4 min · array · brainteaser · leetcode · simulation · Last updated: Jul 26, 2025

Last Person to Fit in the Bus

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Latest Time by Replacing Hidden Digits

November 29, 2024 · 4 min · greedy · leetcode · string · Last updated: Aug 2, 2025

Least Number of Unique Integers after K Removals

November 29, 2024 · 4 min · array · counting · greedy · hash-table · leetcode · sorting · Last updated: Aug 2, 2025

Leetflex Banned Accounts

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Length of the Longest Alphabetical Continuous Substring

November 29, 2024 · 3 min · leetcode · string · Last updated: Aug 2, 2025

Length of the Longest Increasing Path

November 29, 2024 · 6 min · array · binary-search · leetcode · sorting · Last updated: Aug 2, 2025

Length of the Longest Valid Substring

November 29, 2024 · 8 min · array · hash-table · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Lexicographically Minimum String After Removing Stars

November 29, 2024 · 5 min · greedy · hash-table · heap-priority-queue · leetcode · stack · string · Last updated: Aug 2, 2025

Lexicographically Smallest Beautiful String

November 29, 2024 · 6 min · greedy · leetcode · string · Last updated: Aug 2, 2025

Lexicographically Smallest String After Applying Operations

November 29, 2024 · 7 min · breadth-first-search · depth-first-search · enumeration · leetcode · string · Last updated: Aug 2, 2025

Lexicographically Smallest String After Substring Operation

November 29, 2024 · 4 min · greedy · leetcode · string · Last updated: Aug 2, 2025

Linked List Frequency

November 29, 2024 · 5 min · counting · hash-table · leetcode · linked-list · Last updated: Aug 2, 2025

Logical OR of Two Binary Grids Represented as Quad-Trees

November 29, 2024 · 7 min · divide-and-conquer · leetcode · tree · Last updated: Aug 2, 2025

Lonely Pixel II

November 29, 2024 · 8 min · array · hash-table · leetcode · matrix · Last updated: Aug 2, 2025

Long Pressed Name

November 29, 2024 · 4 min · leetcode · string · two-pointers · Last updated: Aug 2, 2025

Longer Contiguous Segments of Ones than Zeros

November 29, 2024 · 5 min · leetcode · string · Last updated: Aug 2, 2025

Longest Alternating Subarray

November 29, 2024 · 5 min · array · enumeration · leetcode · Last updated: Aug 2, 2025

Longest Common Subsequence Between Sorted Arrays

November 29, 2024 · 4 min · array · counting · hash-table · leetcode · Last updated: Aug 2, 2025

Longest Common Suffix Queries

November 29, 2024 · 16 min · array · leetcode · string · trie · Last updated: Aug 7, 2025

Longest Palindromic Subsequence II

November 29, 2024 · 7 min · dynamic-programming · leetcode · string · Last updated: Jul 25, 2025

Longest Repeating Substring

November 29, 2024 · 8 min · binary-search · dynamic-programming · hash-function · leetcode · rolling-hash · string · suffix-array · Last updated: Aug 2, 2025

Longest Substring Of All Vowels in Order

November 29, 2024 · 5 min · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Longest Uncommon Subsequence I

November 29, 2024 · 3 min · leetcode · string · Last updated: Aug 2, 2025

Longest Winning Streak

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Longest Word in Dictionary

November 29, 2024 · 7 min · array · hash-table · leetcode · sorting · string · trie · Last updated: Aug 2, 2025

Make Array Elements Equal to Zero

November 29, 2024 · 7 min · array · leetcode · prefix-sum · simulation · Last updated: Aug 2, 2025

Make Array Empty

November 29, 2024 · 7 min · array · binary-indexed-tree · binary-search · greedy · leetcode · ordered-set · segment-tree · sorting · Last updated: Aug 2, 2025

Make Array Non-decreasing or Non-increasing

November 29, 2024 · 8 min · dynamic-programming · greedy · leetcode · Last updated: Aug 2, 2025

Make Costs of Paths Equal in a Binary Tree

November 29, 2024 · 5 min · array · binary-tree · dynamic-programming · greedy · leetcode · tree · Last updated: Aug 2, 2025

Make K-Subarray Sums Equal

November 29, 2024 · 6 min · array · leetcode · math · number-theory · sorting · Last updated: Aug 2, 2025

Make Number of Distinct Characters Equal

November 29, 2024 · 6 min · counting · hash-table · leetcode · string · Last updated: Aug 2, 2025

Make String Anti-palindrome

November 29, 2024 · 7 min · counting-sort · greedy · leetcode · sorting · string · Last updated: Aug 2, 2025

Make the XOR of All Segments Equal to Zero

November 29, 2024 · 7 min · array · bit-manipulation · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Making File Names Unique

November 29, 2024 · 6 min · array · hash-table · leetcode · string · Last updated: Aug 2, 2025

Market Analysis I

November 29, 2024 · 4 min · database · leetcode · Last updated: Jul 15, 2025

Market Analysis III

November 29, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

Masking Personal Information

November 29, 2024 · 6 min · leetcode · string · Last updated: Aug 2, 2025

Matrix Cells in Distance Order

November 29, 2024 · 4 min · array · geometry · leetcode · math · matrix · sorting · Last updated: Aug 2, 2025

Matrix Similarity After Cyclic Shifts

November 29, 2024 · 5 min · array · leetcode · math · matrix · simulation · Last updated: Aug 2, 2025

Max Consecutive Ones

November 29, 2024 · 3 min · array · leetcode · Last updated: Aug 2, 2025

Max Consecutive Ones II

November 29, 2024 · 4 min · array · dynamic-programming · leetcode · sliding-window · Last updated: Aug 2, 2025

Max Consecutive Ones III

November 29, 2024 · 4 min · array · binary-search · leetcode · prefix-sum · sliding-window · Last updated: Aug 2, 2025

Maximize Area of Square Hole in Grid

November 29, 2024 · 7 min · array · leetcode · sorting · Last updated: Aug 2, 2025

Maximize Distance to Closest Person

November 29, 2024 · 5 min · array · leetcode · Last updated: Aug 2, 2025

Maximize Greatness of an Array

November 29, 2024 · 4 min · array · greedy · leetcode · sorting · two-pointers · Last updated: Aug 2, 2025

Maximize Items

November 29, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

Maximize Number of Nice Divisors

November 29, 2024 · 6 min · leetcode · math · number-theory · recursion · Last updated: Aug 2, 2025

Maximize Sum Of Array After K Negations

November 29, 2024 · 4 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Maximize Sum of Weights after Edge Removals

November 29, 2024 · 6 min · depth-first-search · dynamic-programming · leetcode · tree · Last updated: Aug 2, 2025

Maximize the Number of Partitions After Operations

November 29, 2024 · 6 min · bit-manipulation · bitmask · dynamic-programming · leetcode · string · Last updated: Aug 2, 2025

Maximize the Profit as the Salesman

November 29, 2024 · 5 min · array · binary-search · dynamic-programming · hash-table · leetcode · sorting · Last updated: Aug 2, 2025

Maximize the Topmost Element After K Moves

November 29, 2024 · 6 min · array · greedy · leetcode · Last updated: Aug 2, 2025

Maximize Total Cost of Alternating Subarrays

November 29, 2024 · 5 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Maximize Value of Function in a Ball Passing Game

November 29, 2024 · 8 min · array · bit-manipulation · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Maximum Average Subarray I

November 29, 2024 · 4 min · array · leetcode · sliding-window · Last updated: Aug 2, 2025

Maximum Average Subarray II

November 29, 2024 · 6 min · array · binary-search · leetcode · prefix-sum · Last updated: Aug 2, 2025

Maximum Average Subtree

November 29, 2024 · 5 min · binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Maximum Binary String After Change

November 29, 2024 · 5 min · greedy · leetcode · string · Last updated: Aug 2, 2025

Maximum Binary Tree II

November 29, 2024 · 4 min · binary-tree · leetcode · tree · Last updated: Aug 2, 2025

Maximum Building Height

November 29, 2024 · 7 min · array · leetcode · math · sorting · Last updated: Aug 2, 2025

Maximum Coins Heroes Can Collect

November 29, 2024 · 7 min · array · binary-search · leetcode · prefix-sum · sorting · two-pointers · Last updated: Aug 2, 2025

Maximum Compatibility Score Sum

November 29, 2024 · 7 min · array · backtracking · bit-manipulation · bitmask · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Maximum Depth of N-ary Tree

November 29, 2024 · 3 min · breadth-first-search · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Maximum Distance Between a Pair of Values

November 29, 2024 · 4 min · array · binary-search · leetcode · two-pointers · Last updated: Aug 2, 2025

Maximum Elegance of a K-Length Subsequence

November 29, 2024 · 7 min · array · greedy · hash-table · heap-priority-queue · leetcode · sorting · stack · Last updated: Aug 2, 2025

Maximum Enemy Forts That Can Be Captured

November 29, 2024 · 5 min · array · leetcode · two-pointers · Last updated: Aug 2, 2025

Maximum Equal Frequency

November 29, 2024 · 6 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

Maximum Font to Fit a Sentence in a Screen

November 29, 2024 · 7 min · array · binary-search · interactive · leetcode · string · Last updated: Aug 2, 2025

Maximum Frequency of an Element After Performing Operations I

November 29, 2024 · 5 min · array · binary-search · leetcode · prefix-sum · sliding-window · sorting · Last updated: Aug 2, 2025

Maximum Fruits Harvested After at Most K Steps

November 29, 2024 · 7 min · array · binary-search · leetcode · prefix-sum · sliding-window · Last updated: Aug 3, 2025

Maximum GCD-Sum of a Subarray

November 29, 2024 · 7 min · array · binary-search · leetcode · math · number-theory · Last updated: Aug 2, 2025

Maximum Genetic Difference Query

November 29, 2024 · 14 min · array · bit-manipulation · depth-first-search · hash-table · leetcode · trie · Last updated: Aug 2, 2025

Maximum Good People Based on Statements

November 29, 2024 · 9 min · array · backtracking · bit-manipulation · enumeration · leetcode · Last updated: Aug 2, 2025

Maximum Hamming Distances

November 29, 2024 · 6 min · array · bit-manipulation · breadth-first-search · leetcode · Last updated: Aug 2, 2025

Maximum Increasing Triplet Value

November 29, 2024 · 6 min · array · leetcode · ordered-set · Last updated: Aug 2, 2025

Maximum Length Substring With Two Occurrences

November 29, 2024 · 4 min · hash-table · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Maximum Linear Stock Score

November 29, 2024 · 4 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

Maximum Multiplication Score

November 29, 2024 · 6 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Maximum Number of Alloys

November 29, 2024 · 9 min · array · binary-search · leetcode · Last updated: Aug 2, 2025

Maximum Number of Coins You Can Get

November 29, 2024 · 4 min · array · game-theory · greedy · leetcode · math · sorting · Last updated: Aug 2, 2025

Maximum Number of Darts Inside of a Circular Dartboard

November 29, 2024 · 8 min · array · geometry · leetcode · math · Last updated: Aug 2, 2025

Maximum Number of Groups With Increasing Length

November 29, 2024 · 5 min · array · binary-search · greedy · leetcode · math · sorting · Last updated: Aug 2, 2025

Maximum Number of Jumps to Reach the Last Index

November 29, 2024 · 6 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Maximum Number of Ones

November 29, 2024 · 5 min · greedy · heap-priority-queue · leetcode · Last updated: Aug 2, 2025

Maximum Number of Operations to Move Ones to the End

November 29, 2024 · 4 min · counting · greedy · leetcode · string · Last updated: Aug 2, 2025

Maximum Number of Operations With the Same Score II

November 29, 2024 · 11 min · array · dynamic-programming · leetcode · memoization · Last updated: Aug 2, 2025

Maximum Number of Removal Queries That Can Be Processed I

November 29, 2024 · 7 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Maximum Number of Upgradable Servers

November 29, 2024 · 6 min · array · binary-search · leetcode · math · Last updated: Aug 2, 2025

Maximum Number of Visible Points

November 29, 2024 · 7 min · array · geometry · leetcode · math · sliding-window · sorting · Last updated: Aug 2, 2025

Maximum Number of Vowels in a Substring of Given Length

November 29, 2024 · 4 min · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Maximum Number of Ways to Partition an Array

November 29, 2024 · 9 min · array · counting · enumeration · hash-table · leetcode · prefix-sum · Last updated: Aug 2, 2025

Maximum Number of Weeks for Which You Can Work

November 29, 2024 · 5 min · array · greedy · leetcode · Last updated: Aug 2, 2025

Maximum Number That Sum of the Prices Is Less Than or Equal to K

November 29, 2024 · 8 min · binary-search · bit-manipulation · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Maximum of Absolute Value Expression

November 29, 2024 · 5 min · array · leetcode · math · Last updated: Aug 2, 2025

Maximum of Minimum Values in All Subarrays

November 29, 2024 · 8 min · array · leetcode · monotonic-stack · stack · Last updated: Aug 2, 2025

Maximum Palindromes After Operations

November 29, 2024 · 7 min · array · counting · greedy · hash-table · leetcode · sorting · string · Last updated: Aug 2, 2025

Maximum Points in an Archery Competition

November 29, 2024 · 8 min · array · backtracking · bit-manipulation · enumeration · leetcode · Last updated: Aug 2, 2025

Maximum Points Inside the Square

November 29, 2024 · 7 min · array · binary-search · hash-table · leetcode · sorting · string · Last updated: Aug 2, 2025

Maximum Population Year

November 29, 2024 · 3 min · array · counting · leetcode · prefix-sum · Last updated: Aug 2, 2025

Maximum Possible Number by Binary Concatenation

November 29, 2024 · 5 min · array · bit-manipulation · enumeration · leetcode · Last updated: Aug 2, 2025

Maximum Price to Fill a Bag

November 29, 2024 · 6 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Maximum Repeating Substring

November 29, 2024 · 3 min · dynamic-programming · leetcode · string · string-matching · Last updated: Jan 1, 2025

Maximum Rows Covered by Columns

November 29, 2024 · 6 min · array · backtracking · bit-manipulation · enumeration · leetcode · matrix · Last updated: Aug 2, 2025

Maximum Running Time of N Computers

November 29, 2024 · 6 min · array · binary-search · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Maximum Score After Applying Operations on a Tree

November 29, 2024 · 8 min · depth-first-search · dynamic-programming · leetcode · tree · Last updated: Aug 2, 2025

Maximum Score of a Node Sequence

November 29, 2024 · 9 min · array · enumeration · graph · leetcode · sorting · Last updated: Aug 2, 2025

Maximum Sized Array

November 29, 2024 · 8 min · binary-search · bit-manipulation · leetcode · Last updated: Aug 2, 2025

Maximum Square Area by Removing Fences From a Field

November 29, 2024 · 7 min · array · enumeration · hash-table · leetcode · Last updated: Aug 2, 2025

Maximum Strength of a Group

November 29, 2024 · 6 min · array · backtracking · bit-manipulation · dynamic-programming · enumeration · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Maximum Strong Pair XOR II

November 29, 2024 · 9 min · array · bit-manipulation · hash-table · leetcode · sliding-window · trie · Last updated: Aug 2, 2025

Maximum Subarray Sum After One Operation

November 29, 2024 · 4 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Maximum Subtree of the Same Color

November 29, 2024 · 7 min · array · depth-first-search · dynamic-programming · leetcode · tree · Last updated: Aug 2, 2025

Maximum Sum Obtained of Any Permutation

November 29, 2024 · 6 min · array · greedy · leetcode · prefix-sum · sorting · Last updated: Aug 2, 2025

Maximum Sum of an Hourglass

November 29, 2024 · 4 min · array · leetcode · matrix · prefix-sum · Last updated: Aug 2, 2025

Maximum Sum Queries

November 29, 2024 · 9 min · array · binary-indexed-tree · binary-search · leetcode · monotonic-stack · segment-tree · sorting · stack · Last updated: Aug 2, 2025

Maximum Sum With Exactly K Elements

November 29, 2024 · 5 min · array · greedy · leetcode · Last updated: Aug 2, 2025

Maximum Total Beauty of the Gardens

November 29, 2024 · 10 min · array · binary-search · greedy · leetcode · sorting · two-pointers · Last updated: Aug 2, 2025

Maximum Total Damage With Spell Casting

November 29, 2024 · 6 min · array · binary-search · counting · dynamic-programming · hash-table · leetcode · sorting · two-pointers · Last updated: Aug 2, 2025

Maximum Trailing Zeros in a Cornered Path

November 29, 2024 · 12 min · array · leetcode · matrix · prefix-sum · Last updated: Aug 2, 2025

Maximum Vacation Days

November 29, 2024 · 8 min · array · dynamic-programming · leetcode · matrix · Last updated: Aug 2, 2025

Maximum Value Sum by Placing Three Rooks I

November 29, 2024 · 7 min · array · dynamic-programming · enumeration · leetcode · matrix · Last updated: Aug 2, 2025

Maximum XOR After Operations

November 29, 2024 · 3 min · array · bit-manipulation · leetcode · math · Last updated: Aug 2, 2025

Maximum XOR of Two Non-Overlapping Subtrees

November 29, 2024 · 6 min · depth-first-search · graph · leetcode · tree · trie · Last updated: Aug 2, 2025

Maximum XOR Score Subarray Queries

November 29, 2024 · 6 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Mean of Array After Removing Some Elements

November 29, 2024 · 3 min · array · leetcode · sorting · Last updated: Aug 2, 2025

Median of a Row Wise Sorted Matrix

November 29, 2024 · 7 min · array · binary-search · leetcode · matrix · Last updated: Aug 2, 2025

Memoize II

November 29, 2024 · 4 min · leetcode · Last updated: Aug 2, 2025

Merge BSTs to Create Single BST

November 29, 2024 · 11 min · binary-search · binary-tree · depth-first-search · hash-table · leetcode · tree · Last updated: Aug 2, 2025

Merge Similar Items

November 29, 2024 · 5 min · array · hash-table · leetcode · ordered-set · sorting · Last updated: Aug 2, 2025

Merge Strings Alternately

November 29, 2024 · 4 min · leetcode · string · two-pointers · Last updated: Aug 2, 2025

Min Max Game

November 29, 2024 · 4 min · array · leetcode · simulation · Last updated: Aug 2, 2025

Minimize Length of Array Using Operations

November 29, 2024 · 5 min · array · greedy · leetcode · math · number-theory · Last updated: Aug 2, 2025

Minimize Result by Adding Parentheses to Expression

November 29, 2024 · 6 min · enumeration · leetcode · string · Last updated: Aug 2, 2025

Minimize Rounding Error to Meet Target

November 29, 2024 · 6 min · array · greedy · leetcode · math · sorting · string · Last updated: Aug 2, 2025

Minimize String Length

November 29, 2024 · 3 min · hash-table · leetcode · string · Last updated: Aug 2, 2025

Minimize the Difference Between Target and Chosen Elements

November 29, 2024 · 5 min · array · dynamic-programming · leetcode · matrix · Last updated: Aug 2, 2025

Minimize the Maximum Adjacent Element Difference

November 29, 2024 · 11 min · array · binary-search · greedy · leetcode · Last updated: Aug 2, 2025

Minimize the Total Price of the Trips

November 29, 2024 · 10 min · array · depth-first-search · dynamic-programming · graph · leetcode · tree · Last updated: Aug 2, 2025

Minimizing Array After Replacing Pairs With Their Product

November 29, 2024 · 6 min · array · dynamic-programming · greedy · leetcode · Last updated: Aug 2, 2025

Minimum Absolute Difference Between Elements With Constraint

November 29, 2024 · 5 min · array · binary-search · leetcode · ordered-set · Last updated: Aug 2, 2025

Minimum Additions to Make Valid String

November 29, 2024 · 2 min · dynamic-programming · greedy · leetcode · stack · string · Last updated: Jul 26, 2025

Minimum Area Rectangle II

November 29, 2024 · 3 min · array · geometry · leetcode · math · Last updated: Aug 2, 2025

Minimum Array Changes to Make Differences Equal

November 29, 2024 · 3 min · array · hash-table · leetcode · prefix-sum · Last updated: Aug 2, 2025

Minimum Array Length After Pair Removals

November 29, 2024 · 4 min · array · binary-search · counting · greedy · hash-table · leetcode · two-pointers · Last updated: Aug 2, 2025

Minimum Changes To Make Alternating Binary String

November 29, 2024 · 4 min · leetcode · string · Last updated: Aug 2, 2025

Minimum Changes to Make K Semi-palindromes

November 29, 2024 · 11 min · dynamic-programming · leetcode · string · two-pointers · Last updated: Aug 2, 2025

Minimum Consecutive Cards to Pick Up

November 29, 2024 · 4 min · array · hash-table · leetcode · sliding-window · Last updated: Aug 2, 2025

Minimum Cost for Cutting Cake I

November 29, 2024 · 7 min · array · dynamic-programming · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Minimum Cost of a Path With Special Roads

November 29, 2024 · 9 min · array · graph · heap-priority-queue · leetcode · shortest-path · Last updated: Aug 2, 2025

Minimum Cost of Buying Candies With Discount

November 29, 2024 · 4 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Minimum Cost to Change the Final Value of Expression

November 29, 2024 · 11 min · dynamic-programming · leetcode · math · stack · string · Last updated: Aug 2, 2025

Minimum Cost to Connect Sticks

November 29, 2024 · 5 min · array · greedy · heap-priority-queue · leetcode · Last updated: Aug 2, 2025

Minimum Cost to Convert String II

November 29, 2024 · 10 min · array · dynamic-programming · graph · leetcode · shortest-path · string · trie · Last updated: Aug 2, 2025

Minimum Cuts to Divide a Circle

November 29, 2024 · 3 min · geometry · leetcode · math · Last updated: Aug 2, 2025

Minimum Degree of a Connected Trio in a Graph

November 29, 2024 · 6 min · graph · leetcode · Last updated: Aug 2, 2025

Minimum Edge Reversals So Every Node Is Reachable

November 29, 2024 · 9 min · breadth-first-search · depth-first-search · dynamic-programming · graph · leetcode · Last updated: Aug 2, 2025

Minimum Element After Replacement With Digit Sum

November 29, 2024 · 4 min · array · leetcode · math · Last updated: Aug 2, 2025

Minimum Elements to Add to Form a Given Sum

November 29, 2024 · 3 min · array · greedy · leetcode · Last updated: Aug 2, 2025

Minimum Garden Perimeter to Collect Enough Apples

November 29, 2024 · 5 min · binary-search · leetcode · math · Last updated: Aug 2, 2025

Minimum Hours of Training to Win a Competition

November 29, 2024 · 6 min · array · greedy · leetcode · Last updated: Aug 2, 2025

Minimum Increment Operations to Make Array Beautiful

November 29, 2024 · 6 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Minimum Index of a Valid Split

November 29, 2024 · 5 min · array · hash-table · leetcode · sorting · Last updated: Aug 2, 2025

Minimum Index Sum of Two Lists

November 29, 2024 · 5 min · array · hash-table · leetcode · string · Last updated: Aug 2, 2025

Minimum Insertions to Balance a Parentheses String

November 29, 2024 · 3 min · greedy · leetcode · stack · string · Last updated: Jul 27, 2025

Minimum Knight Moves

November 29, 2024 · 6 min · breadth-first-search · leetcode · Last updated: Aug 2, 2025

Minimum Length of Anagram Concatenation

November 29, 2024 · 5 min · counting · hash-table · leetcode · string · Last updated: Aug 2, 2025

Minimum Levels to Gain More Points

November 29, 2024 · 6 min · array · leetcode · prefix-sum · Last updated: Aug 2, 2025

Minimum Lines to Represent a Line Chart

November 29, 2024 · 5 min · array · geometry · leetcode · math · number-theory · sorting · Last updated: Aug 2, 2025

Minimum Money Required Before Transactions

November 29, 2024 · 4 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Minimum Moves to Capture The Queen

November 29, 2024 · 7 min · array · enumeration · leetcode · math · Last updated: Aug 2, 2025

Minimum Moves to Make Array Complementary

November 29, 2024 · 6 min · array · hash-table · leetcode · prefix-sum · Last updated: Aug 2, 2025

Minimum Moves to Move a Box to Their Target Location

November 29, 2024 · 16 min · array · breadth-first-search · heap-priority-queue · leetcode · matrix · Last updated: Aug 2, 2025

Minimum Moves to Pick K Ones

November 29, 2024 · 9 min · array · greedy · leetcode · prefix-sum · sliding-window · Last updated: Aug 2, 2025

Minimum Moves to Reach Target Score

November 29, 2024 · 4 min · greedy · leetcode · math · Last updated: Aug 2, 2025

Minimum Moves to Spread Stones Over Grid

November 29, 2024 · 8 min · array · breadth-first-search · dynamic-programming · leetcode · matrix · Last updated: Aug 2, 2025

Minimum Number Game

November 29, 2024 · 3 min · array · heap-priority-queue · leetcode · simulation · sorting · Last updated: Aug 2, 2025

Minimum Number of Coins for Fruits

November 29, 2024 · 5 min · array · dynamic-programming · heap-priority-queue · leetcode · monotonic-queue · queue · Last updated: Aug 2, 2025

Minimum Number of Coins to be Added

November 29, 2024 · 5 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Minimum Number of Flips to Convert Binary Matrix to Zero Matrix

November 29, 2024 · 8 min · array · bit-manipulation · breadth-first-search · hash-table · leetcode · matrix · Last updated: Aug 2, 2025

Minimum Number of Flips to Make Binary Grid Palindromic I

November 29, 2024 · 5 min · array · leetcode · matrix · two-pointers · Last updated: Aug 2, 2025

Minimum Number of Flips to Make Binary Grid Palindromic II

November 29, 2024 · 9 min · array · leetcode · matrix · two-pointers · Last updated: Aug 2, 2025

Minimum Number of Food Buckets to Feed the Hamsters

November 29, 2024 · 5 min · dynamic-programming · greedy · leetcode · string · Last updated: Aug 2, 2025

Minimum Number of Groups to Create a Valid Assignment

November 29, 2024 · 3 min · array · greedy · hash-table · leetcode · Last updated: Aug 2, 2025

Minimum Number of Increments on Subarrays to Form a Target Array

November 29, 2024 · 3 min · array · dynamic-programming · greedy · leetcode · monotonic-stack · stack · Last updated: Aug 2, 2025

Minimum Number of K Consecutive Bit Flips

November 29, 2024 · 5 min · array · bit-manipulation · leetcode · prefix-sum · queue · sliding-window · Last updated: Aug 2, 2025

Minimum Number of Keypresses

November 29, 2024 · 4 min · counting · greedy · hash-table · leetcode · sorting · string · Last updated: Jul 26, 2025

Minimum Number of Operations to Make Array XOR Equal to K

November 29, 2024 · 4 min · array · bit-manipulation · leetcode · Last updated: Aug 2, 2025

Minimum Number of Operations to Make Word K-Periodic

November 29, 2024 · 5 min · counting · hash-table · leetcode · string · Last updated: Aug 2, 2025

Minimum Number of Operations to Reinitialize a Permutation

November 29, 2024 · 4 min · array · leetcode · math · simulation · Last updated: Aug 2, 2025

Minimum Number of Seconds to Make Mountain Height Zero

November 29, 2024 · 8 min · array · binary-search · greedy · heap-priority-queue · leetcode · math · Last updated: Aug 2, 2025

Minimum Number of Steps to Make Two Strings Anagram

November 29, 2024 · 4 min · counting · hash-table · leetcode · string · Last updated: Aug 2, 2025

Minimum Number of Steps to Make Two Strings Anagram II

November 29, 2024 · 4 min · counting · hash-table · leetcode · string · Last updated: Aug 2, 2025

Minimum Number of Swaps to Make the Binary String Alternating

November 29, 2024 · 6 min · greedy · leetcode · string · Last updated: Aug 2, 2025

Minimum Number of Valid Strings to Form Target I

November 29, 2024 · 6 min · array · binary-search · dynamic-programming · hash-function · leetcode · rolling-hash · segment-tree · string · string-matching · trie · Last updated: Aug 2, 2025

Minimum Operations to Collect Elements

November 29, 2024 · 4 min · array · bit-manipulation · hash-table · leetcode · Last updated: Aug 2, 2025

Minimum Operations to Convert Number

November 29, 2024 · 6 min · array · breadth-first-search · leetcode · Last updated: Aug 2, 2025

Minimum Operations to Exceed Threshold Value 1

November 29, 2024 · 5 min · array · leetcode · Last updated: Aug 2, 2025

Minimum Operations to Form Subsequence With Target Sum

November 29, 2024 · 7 min · array · bit-manipulation · greedy · leetcode · Last updated: Aug 2, 2025

Minimum Operations to Halve Array Sum

November 29, 2024 · 6 min · array · greedy · heap-priority-queue · leetcode · Last updated: Aug 2, 2025

Minimum Operations to Make Array Equal

November 29, 2024 · 3 min · leetcode · math · Last updated: Aug 2, 2025

Minimum Operations to Make the Array Increasing

November 29, 2024 · 4 min · array · greedy · leetcode · Last updated: Aug 2, 2025

Minimum Operations to Make the Array K-Increasing

November 29, 2024 · 7 min · array · binary-search · leetcode · Last updated: Aug 2, 2025

Minimum Operations to Make the Integer Zero

November 29, 2024 · 4 min · bit-manipulation · brainteaser · leetcode · Last updated: Aug 2, 2025

Minimum Operations to Reduce an Integer to 0

November 29, 2024 · 5 min · bit-manipulation · dynamic-programming · greedy · leetcode · Last updated: Aug 2, 2025

Minimum Operations to Remove Adjacent Ones in Matrix

November 29, 2024 · 4 min · array · graph · leetcode · matrix · Last updated: Aug 2, 2025

Minimum Operations to Write the Letter Y on a Grid

November 29, 2024 · 7 min · array · counting · hash-table · leetcode · matrix · Last updated: Aug 2, 2025

Minimum Path Cost in a Hidden Grid

November 29, 2024 · 7 min · breadth-first-search · depth-first-search · graph · heap-priority-queue · interactive · leetcode · Last updated: Aug 2, 2025

Minimum Penalty for a Shop

November 29, 2024 · 5 min · leetcode · prefix-sum · string · Last updated: Aug 2, 2025

Minimum Relative Loss After Buying Chocolates

November 29, 2024 · 7 min · array · binary-search · leetcode · prefix-sum · sorting · Last updated: Aug 2, 2025

Minimum Replacements to Sort the Array

November 29, 2024 · 4 min · array · greedy · leetcode · math · Last updated: Aug 2, 2025

Minimum Reverse Operations

November 29, 2024 · 6 min · array · breadth-first-search · leetcode · ordered-set · Last updated: Aug 2, 2025

Minimum Right Shifts to Sort the Array

November 29, 2024 · 4 min · array · leetcode · Last updated: Aug 2, 2025

Minimum Score After Removals on a Tree

November 29, 2024 · 19 min · array · bit-manipulation · depth-first-search · leetcode · tree · Last updated: Jul 24, 2025

Minimum Sideway Jumps

November 29, 2024 · 5 min · array · dynamic-programming · greedy · leetcode · Last updated: Aug 2, 2025

Minimum Size Subarray in Infinite Array

November 29, 2024 · 6 min · array · hash-table · leetcode · prefix-sum · sliding-window · Last updated: Aug 2, 2025

Minimum Substring Partition of Equal Character Frequency

November 29, 2024 · 5 min · counting · dynamic-programming · hash-table · leetcode · string · Last updated: Aug 2, 2025

Minimum Sum of Four Digit Number After Splitting Digits

November 29, 2024 · 3 min · greedy · leetcode · math · sorting · Last updated: Aug 2, 2025

Minimum Sum of Mountain Triplets I

November 29, 2024 · 5 min · array · leetcode · Last updated: Aug 2, 2025

Minimum Swaps to Arrange a Binary Grid

November 29, 2024 · 6 min · array · greedy · leetcode · matrix · Last updated: Aug 2, 2025

Minimum Swaps to Make Strings Equal

November 29, 2024 · 4 min · greedy · leetcode · math · string · Last updated: Aug 2, 2025

Minimum Time For K Virus Variants to Spread

November 29, 2024 · 6 min · array · binary-search · enumeration · geometry · leetcode · math · Last updated: Aug 2, 2025

Minimum Time Takes to Reach Destination Without Drowning

November 29, 2024 · 10 min · array · breadth-first-search · leetcode · matrix · Last updated: Aug 2, 2025

Minimum Time to Complete All Tasks

November 29, 2024 · 5 min · array · binary-search · greedy · leetcode · sorting · stack · Last updated: Aug 2, 2025

Minimum Time to Revert Word to Initial State I

November 29, 2024 · 5 min · hash-function · leetcode · rolling-hash · string · string-matching · Last updated: Jan 1, 2025

Minimum Time to Revert Word to Initial State II

November 29, 2024 · 4 min · hash-function · leetcode · rolling-hash · string · string-matching · Last updated: Jan 1, 2025

Minimum Time to Type Word Using Special Typewriter

November 29, 2024 · 5 min · greedy · leetcode · string · Last updated: Jan 1, 2025

Minimum Time to Visit a Cell In a Grid

November 29, 2024 · 5 min · array · breadth-first-search · graph · heap-priority-queue · leetcode · matrix · shortest-path · Last updated: Aug 2, 2025

Minimum Total Operations

November 29, 2024 · 3 min · array · leetcode · Last updated: Aug 2, 2025

Minimum Total Space Wasted With K Resizing Operations

November 29, 2024 · 7 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Minimum Window Subsequence

November 29, 2024 · 7 min · dynamic-programming · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Missing Number In Arithmetic Progression

November 29, 2024 · 4 min · array · leetcode · math · Last updated: Aug 2, 2025

Monotonic Array

November 29, 2024 · 2 min · array · leetcode · Last updated: Aug 2, 2025

Monthly Transactions I

November 29, 2024 · 2 min · database · leetcode · Last updated: Aug 2, 2025

Monthly Transactions II

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Most Frequent IDs

November 29, 2024 · 4 min · array · hash-table · heap-priority-queue · leetcode · ordered-set · Last updated: Aug 2, 2025

Most Frequent Prime

November 29, 2024 · 5 min · array · counting · enumeration · hash-table · leetcode · math · matrix · number-theory · Last updated: Aug 2, 2025

Most Popular Video Creator

November 29, 2024 · 4 min · array · hash-table · heap-priority-queue · leetcode · sorting · string · Last updated: Aug 2, 2025

Most Visited Sector in a Circular Track

November 29, 2024 · 3 min · array · leetcode · simulation · Last updated: Aug 2, 2025

Movement of Robots

November 29, 2024 · 5 min · array · brainteaser · leetcode · prefix-sum · sorting · Last updated: Aug 2, 2025

Moving Stones Until Consecutive

November 29, 2024 · 3 min · brainteaser · leetcode · math · Last updated: Aug 2, 2025

N-Repeated Element in Size 2N Array

November 29, 2024 · 2 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

Nearest Exit from Entrance in Maze

November 29, 2024 · 8 min · array · breadth-first-search · leetcode · matrix · Last updated: Aug 2, 2025

Neither Minimum nor Maximum

November 29, 2024 · 3 min · array · leetcode · sorting · Last updated: Aug 2, 2025

Next Closest Time

November 29, 2024 · 6 min · backtracking · enumeration · hash-table · leetcode · string · Last updated: Aug 2, 2025

Next Day

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Next Greater Node In Linked List

November 29, 2024 · 4 min · array · leetcode · linked-list · monotonic-stack · stack · Last updated: Aug 2, 2025

Next Greater Numerically Balanced Number

November 29, 2024 · 5 min · backtracking · enumeration · leetcode · math · Last updated: Aug 2, 2025

Number of Adjacent Elements With the Same Color

November 29, 2024 · 6 min · array · leetcode · Last updated: Aug 2, 2025

Number of Beautiful Integers in the Range

November 29, 2024 · 4 min · dynamic-programming · leetcode · math · Last updated: Aug 2, 2025

Number of Beautiful Pairs

November 29, 2024 · 6 min · array · counting · hash-table · leetcode · math · number-theory · Last updated: Aug 2, 2025

Number of Changing Keys

November 29, 2024 · 3 min · leetcode · string · Last updated: Aug 2, 2025

Number of Common Factors

November 29, 2024 · 3 min · enumeration · leetcode · math · number-theory · Last updated: Aug 2, 2025

Number Of Corner Rectangles

November 29, 2024 · 4 min · array · dynamic-programming · leetcode · math · matrix · Last updated: Aug 2, 2025

Number of Days Between Two Dates

November 29, 2024 · 5 min · leetcode · math · string · Last updated: Aug 2, 2025

Number of Different Subsequences GCDs

November 29, 2024 · 5 min · array · counting · leetcode · math · number-theory · Last updated: Aug 2, 2025

Number of Distinct Binary Strings After Applying Operations

November 29, 2024 · 4 min · leetcode · math · string · Last updated: Aug 2, 2025

Number of Distinct Islands

November 29, 2024 · 5 min · breadth-first-search · depth-first-search · hash-function · hash-table · leetcode · union-find · Last updated: Aug 2, 2025

Number of Divisible Substrings

November 29, 2024 · 6 min · counting · hash-table · leetcode · prefix-sum · string · Last updated: Aug 2, 2025

Number of Equal Count Substrings

November 29, 2024 · 8 min · counting · leetcode · prefix-sum · string · Last updated: Aug 2, 2025

Number of Equivalent Domino Pairs

November 29, 2024 · 3 min · array · counting · hash-table · leetcode · Last updated: Aug 2, 2025

Number of Great Partitions

November 29, 2024 · 7 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Number of Laser Beams in a Bank

November 29, 2024 · 4 min · array · leetcode · math · matrix · string · Last updated: Aug 2, 2025

Number of Lines To Write String

November 29, 2024 · 4 min · array · leetcode · string · Last updated: Aug 2, 2025

Number of Matching Subsequences

November 29, 2024 · 5 min · array · binary-search · dynamic-programming · hash-table · leetcode · sorting · string · trie · Last updated: Aug 2, 2025

Number of Nodes With Value One

November 29, 2024 · 6 min · binary-tree · breadth-first-search · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Number of Possible Sets of Closing Branches

November 29, 2024 · 12 min · bit-manipulation · enumeration · graph · heap-priority-queue · leetcode · shortest-path · Last updated: Aug 2, 2025

Number of Recent Calls

November 29, 2024 · 4 min · data-stream · design · leetcode · queue · Last updated: Aug 2, 2025

Number Of Rectangles That Can Form The Largest Square

November 29, 2024 · 4 min · array · leetcode · Last updated: Aug 2, 2025

Number of Same-End Substrings

November 29, 2024 · 6 min · array · counting · hash-table · leetcode · prefix-sum · string · Last updated: Aug 2, 2025

Number of Ships in a Rectangle

November 29, 2024 · 8 min · array · divide-and-conquer · interactive · leetcode · Last updated: Jul 18, 2025

Number of Single Divisor Triplets

November 29, 2024 · 8 min · leetcode · math · Last updated: Aug 2, 2025

Number of Smooth Descent Periods of a Stock

November 29, 2024 · 4 min · array · dynamic-programming · leetcode · math · Last updated: Aug 2, 2025

Number of Strings That Appear as Substrings in Word

November 29, 2024 · 3 min · array · leetcode · string · Last updated: Aug 2, 2025

Number of Students Unable to Eat Lunch

November 29, 2024 · 6 min · array · leetcode · queue · simulation · stack · Last updated: Aug 2, 2025

Number of Subarrays That Match a Pattern II

November 29, 2024 · 6 min · array · hash-function · leetcode · rolling-hash · string-matching · Last updated: Aug 2, 2025

Number of Substrings With Fixed Ratio

November 29, 2024 · 5 min · hash-table · leetcode · math · prefix-sum · string · Last updated: Aug 2, 2025

Number of Substrings With Only 1s

November 29, 2024 · 4 min · leetcode · math · string · Last updated: Aug 2, 2025

Number of Times a Driver Was a Passenger

November 29, 2024 · 2 min · database · leetcode · Last updated: Aug 2, 2025

Number of Transactions per Visit

November 29, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

Number of Unequal Triplets in Array

November 29, 2024 · 4 min · array · hash-table · leetcode · sorting · Last updated: Aug 2, 2025

Number of Unique Categories

November 29, 2024 · 6 min · counting · interactive · leetcode · union-find · Last updated: Aug 2, 2025

Number of Unique Flavors After Sharing K Candies

November 29, 2024 · 7 min · array · hash-table · leetcode · sliding-window · Last updated: Aug 2, 2025

Number of Valid Subarrays

November 29, 2024 · 4 min · array · leetcode · monotonic-stack · stack · Last updated: Aug 2, 2025

Number of Valid Words in a Sentence

November 29, 2024 · 7 min · leetcode · string · Last updated: Aug 2, 2025

Number of Visible People in a Queue

November 29, 2024 · 5 min · array · leetcode · monotonic-stack · stack · Last updated: Aug 2, 2025

Number of Ways to Buy Pens and Pencils

November 29, 2024 · 4 min · enumeration · leetcode · math · Last updated: Aug 2, 2025

Number of Ways to Earn Points

November 29, 2024 · 6 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Number of Ways to Reach Destination in the Grid

November 29, 2024 · 6 min · combinatorics · dynamic-programming · leetcode · math · Last updated: Aug 2, 2025

Number Of Ways To Reconstruct A Tree

November 29, 2024 · 9 min · graph · leetcode · tree · Last updated: Aug 2, 2025

Number of Ways to Select Buildings

November 29, 2024 · 6 min · dynamic-programming · leetcode · prefix-sum · string · Last updated: Aug 2, 2025

Number of Ways to Split a String

November 29, 2024 · 6 min · leetcode · math · string · Last updated: Aug 2, 2025

Number of Ways Where Square of Number Is Equal to Product of Two Numbers

November 29, 2024 · 5 min · array · hash-table · leetcode · math · two-pointers · Last updated: Aug 2, 2025

Occurrences After Bigram

November 29, 2024 · 3 min · leetcode · string · Last updated: Aug 2, 2025

Odd and Even Transactions

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Online Election

November 29, 2024 · 7 min · array · binary-search · design · hash-table · leetcode · Last updated: Aug 2, 2025

Optimal Division

November 29, 2024 · 4 min · array · dynamic-programming · leetcode · math · Last updated: Aug 2, 2025

Orders With Maximum Quantity Above Average

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Output Contest Matches

November 29, 2024 · 5 min · leetcode · recursion · simulation · string · Last updated: Aug 2, 2025

Page Recommendations

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Parallel Courses

November 29, 2024 · 7 min · graph · leetcode · topological-sort · Last updated: Aug 2, 2025

Parallel Execution of Promises for Individual Results Retrieval

November 29, 2024 · 3 min · leetcode · Last updated: Aug 2, 2025

Parse Lisp Expression

November 29, 2024 · 12 min · hash-table · leetcode · recursion · stack · string · Last updated: Jul 26, 2025

Partition Array Into Two Arrays to Minimize Sum Difference

November 29, 2024 · 9 min · array · binary-search · bit-manipulation · bitmask · dynamic-programming · leetcode · ordered-set · two-pointers · Last updated: Aug 2, 2025

Pass the Pillow

November 29, 2024 · 4 min · leetcode · math · simulation · Last updated: Aug 2, 2025

Path With Maximum Minimum Value

November 29, 2024 · 6 min · array · binary-search · breadth-first-search · depth-first-search · heap-priority-queue · leetcode · matrix · union-find · Last updated: Aug 2, 2025

Paths in Matrix Whose Sum Is Divisible by K

November 29, 2024 · 6 min · array · dynamic-programming · leetcode · matrix · Last updated: Aug 2, 2025

Percentage of Users Attended a Contest

November 29, 2024 · 3 min · database · leetcode · Last updated: Jul 16, 2025

Perform String Shifts

November 29, 2024 · 4 min · array · leetcode · math · string · Last updated: Aug 2, 2025

Permutation Difference between Two Strings

November 29, 2024 · 4 min · hash-table · leetcode · string · Last updated: Aug 2, 2025

Points That Intersect With Cars

November 29, 2024 · 3 min · array · hash-table · leetcode · prefix-sum · Last updated: Aug 2, 2025

Powerful Integers

November 29, 2024 · 4 min · enumeration · hash-table · leetcode · math · Last updated: Aug 2, 2025

Preimage Size of Factorial Zeroes Function

November 29, 2024 · 6 min · binary-search · leetcode · math · Last updated: Aug 2, 2025

Premier League Table Ranking II

November 29, 2024 · 7 min · database · leetcode · Last updated: Aug 2, 2025

Premier League Table Ranking III

November 29, 2024 · 6 min · database · leetcode · Last updated: Aug 2, 2025

Previous Permutation With One Swap

November 29, 2024 · 4 min · array · greedy · leetcode · Last updated: Aug 2, 2025

Prime In Diagonal

November 29, 2024 · 6 min · array · leetcode · math · matrix · number-theory · Last updated: Aug 2, 2025

Prime Number of Set Bits in Binary Representation

November 29, 2024 · 4 min · bit-manipulation · leetcode · math · Last updated: Aug 2, 2025

Prime Palindrome

November 29, 2024 · 7 min · leetcode · math · number-theory · Last updated: Aug 2, 2025

Print Immutable Linked List in Reverse

November 29, 2024 · 4 min · leetcode · linked-list · recursion · stack · two-pointers · Last updated: Aug 2, 2025

Prison Cells After N Days

November 29, 2024 · 5 min · array · bit-manipulation · hash-table · leetcode · math · Last updated: Aug 2, 2025

Product of Two Run-Length Encoded Arrays

November 29, 2024 · 6 min · array · leetcode · two-pointers · Last updated: Aug 2, 2025

Product Sales Analysis V

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Products With Three or More Orders in Two Consecutive Years

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Project Employees III

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Promise Time Limit

November 29, 2024 · 3 min · leetcode · Last updated: Aug 2, 2025

Query Kth Smallest Trimmed Number

November 29, 2024 · 5 min · array · divide-and-conquer · heap-priority-queue · leetcode · quickselect · radix-sort · sorting · string · Last updated: Aug 2, 2025

Range Sum of BST

November 29, 2024 · 4 min · binary-search-tree · binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 10, 2025

Rank Teams by Votes

November 29, 2024 · 6 min · array · counting · hash-table · leetcode · sorting · string · Last updated: Aug 2, 2025

Rank Transform of a Matrix

November 29, 2024 · 9 min · array · graph · leetcode · matrix · sorting · topological-sort · union-find · Last updated: Aug 2, 2025

Reach End of Array With Max Score

November 29, 2024 · 5 min · array · greedy · leetcode · Last updated: Aug 2, 2025

Reconstruct a 2-Row Binary Matrix

November 29, 2024 · 6 min · array · greedy · leetcode · matrix · Last updated: Aug 2, 2025

Redundant Connection II

November 29, 2024 · 8 min · breadth-first-search · depth-first-search · graph · leetcode · union-find · Last updated: Aug 2, 2025

Reformat Department Table

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Remove Adjacent Almost-Equal Characters

November 29, 2024 · 4 min · dynamic-programming · greedy · leetcode · string · Last updated: Aug 2, 2025

Remove All Ones With Row and Column Flips II

November 29, 2024 · 9 min · array · bit-manipulation · breadth-first-search · leetcode · matrix · Last updated: Aug 2, 2025

Remove Comments

November 29, 2024 · 9 min · array · leetcode · string · Last updated: Aug 2, 2025

Remove Digit From Number to Maximize Result

November 29, 2024 · 4 min · enumeration · greedy · leetcode · string · Last updated: Aug 2, 2025

Remove Letter To Equalize Frequency

November 29, 2024 · 4 min · counting · hash-table · leetcode · string · Last updated: Aug 2, 2025

Remove One Element to Make the Array Strictly Increasing

November 29, 2024 · 5 min · array · leetcode · Last updated: Aug 2, 2025

Remove Trailing Zeros From a String

November 29, 2024 · 2 min · leetcode · string · Last updated: Aug 2, 2025

Repeat String

November 29, 2024 · 3 min · leetcode · Last updated: Aug 2, 2025

Repeated String Match

November 29, 2024 · 4 min · leetcode · string · string-matching · Last updated: Aug 2, 2025

Replace Elements in an Array

November 29, 2024 · 4 min · array · hash-table · leetcode · simulation · Last updated: Aug 2, 2025

Replace Question Marks in String to Minimize Its Value

November 29, 2024 · 5 min · counting · greedy · hash-table · heap-priority-queue · leetcode · sorting · string · Last updated: Aug 2, 2025

Report Contiguous Dates

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Report Spam Message

November 29, 2024 · 3 min · array · hash-table · leetcode · string · Last updated: Aug 2, 2025

Reshape Data- Pivot

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Restaurant Growth

November 29, 2024 · 4 min · database · leetcode · Last updated: Jul 15, 2025

Return Length of Arguments Passed

November 29, 2024 · 1 min · leetcode · Last updated: Aug 2, 2025

Reverse Nodes in Even Length Groups

November 29, 2024 · 9 min · leetcode · linked-list · Last updated: Aug 2, 2025

Reverse Only Letters

November 29, 2024 · 4 min · leetcode · string · two-pointers · Last updated: Aug 2, 2025

Reward Top K Students

November 29, 2024 · 7 min · array · hash-table · heap-priority-queue · leetcode · sorting · string · Last updated: Aug 2, 2025

Rolling Average Steps

November 29, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

Root Equals Sum of Children

November 29, 2024 · 2 min · binary-tree · leetcode · tree · Last updated: Aug 2, 2025

Rotated Digits

November 29, 2024 · 5 min · dynamic-programming · leetcode · math · Last updated: Aug 2, 2025

Running Total for Different Genders

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Sales Analysis I

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Sales Analysis III

November 29, 2024 · 3 min · database · leetcode · Last updated: Jul 14, 2025

Second Day Verification

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Second Degree Follower

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Second Largest Digit in a String

November 29, 2024 · 3 min · hash-table · leetcode · string · Last updated: Aug 2, 2025

Second Minimum Node In a Binary Tree

November 29, 2024 · 5 min · binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Select Data

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Sell Diminishing-Valued Colored Balls

November 29, 2024 · 7 min · array · binary-search · greedy · heap-priority-queue · leetcode · math · sorting · Last updated: Aug 2, 2025

Selling Pieces of Wood

November 29, 2024 · 8 min · array · dynamic-programming · leetcode · memoization · Last updated: Aug 2, 2025

Sender With Largest Word Count

November 29, 2024 · 5 min · array · counting · hash-table · leetcode · string · Last updated: Aug 2, 2025

Separate the Digits in an Array

November 29, 2024 · 3 min · array · leetcode · simulation · Last updated: Aug 2, 2025

Set Intersection Size At Least Two

November 29, 2024 · 6 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Shortest and Lexicographically Smallest Beautiful String

November 29, 2024 · 7 min · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Shortest Completing Word

November 29, 2024 · 6 min · array · hash-table · leetcode · string · Last updated: Aug 2, 2025

Shortest Cycle in a Graph

November 29, 2024 · 7 min · breadth-first-search · graph · leetcode · Last updated: Aug 2, 2025

Shortest Distance to a Character

November 29, 2024 · 3 min · array · leetcode · string · two-pointers · Last updated: Aug 2, 2025

Shortest Distance to Target Color

November 29, 2024 · 3 min · array · binary-search · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Shortest Distance to Target String in a Circular Array

November 29, 2024 · 3 min · array · leetcode · string · Last updated: Aug 2, 2025

Sign of the Product of an Array

November 29, 2024 · 2 min · array · leetcode · math · Last updated: Aug 2, 2025

Smallest Divisible Digit Product I

November 29, 2024 · 2 min · enumeration · leetcode · math · Last updated: Aug 2, 2025

Smallest Divisible Digit Product II

November 29, 2024 · 5 min · backtracking · greedy · leetcode · math · number-theory · string · Last updated: Aug 2, 2025

Smallest Index With Equal Value

November 29, 2024 · 2 min · array · leetcode · Last updated: Aug 2, 2025

Smallest Missing Genetic Value in Each Subtree

November 29, 2024 · 5 min · depth-first-search · dynamic-programming · leetcode · tree · union-find · Last updated: Aug 2, 2025

Smallest Missing Integer Greater Than Sequential Prefix Sum

November 29, 2024 · 3 min · array · hash-table · leetcode · sorting · Last updated: Aug 2, 2025

Smallest Number in Infinite Set

November 29, 2024 · 4 min · design · hash-table · heap-priority-queue · leetcode · ordered-set · Last updated: Aug 2, 2025

Smallest Range I

November 29, 2024 · 3 min · array · leetcode · math · Last updated: Aug 2, 2025

Smallest Rotation with Highest Score

November 29, 2024 · 6 min · array · leetcode · prefix-sum · Last updated: Aug 2, 2025

Smallest Subarrays With Maximum Bitwise OR

November 29, 2024 · 6 min · array · binary-search · bit-manipulation · leetcode · sliding-window · Last updated: Aug 2, 2025

Smallest Subsequence of Distinct Characters

November 29, 2024 · 5 min · greedy · leetcode · monotonic-stack · stack · string · Last updated: Aug 2, 2025

Snake in Matrix

November 29, 2024 · 5 min · array · leetcode · simulation · string · Last updated: Aug 2, 2025

Snaps Analysis

November 29, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

Sort Array by Moving Items to Empty Space

November 29, 2024 · 9 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Sort Even and Odd Indices Independently

November 29, 2024 · 7 min · array · leetcode · sorting · Last updated: Aug 2, 2025

Sort Features by Popularity

November 29, 2024 · 8 min · array · hash-table · leetcode · sorting · string · Last updated: Aug 2, 2025

Sort Integers by The Number of 1 Bits

November 29, 2024 · 7 min · array · bit-manipulation · counting · leetcode · sorting · Last updated: Aug 2, 2025

Sort Integers by The Power Value

November 29, 2024 · 10 min · dynamic-programming · leetcode · memoization · sorting · Last updated: Aug 2, 2025

Sorted GCD Pair Queries

November 29, 2024 · 9 min · array · binary-search · combinatorics · counting · hash-table · leetcode · math · number-theory · prefix-sum · Last updated: Aug 2, 2025

Sorting Three Groups

November 29, 2024 · 6 min · array · binary-search · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Special Positions in a Binary Matrix

November 29, 2024 · 5 min · array · leetcode · matrix · Last updated: Jul 26, 2025

Split a Circular Linked List

November 29, 2024 · 4 min · leetcode · linked-list · two-pointers · Last updated: Jul 26, 2025

Split Array with Equal Sum

November 29, 2024 · 6 min · array · hash-table · leetcode · prefix-sum · Last updated: Jul 26, 2025

Split Array With Same Average

November 29, 2024 · 5 min · array · bit-manipulation · bitmask · dynamic-programming · leetcode · math · Last updated: Jul 26, 2025

Split Concatenated Strings

November 29, 2024 · 7 min · array · greedy · leetcode · string · Last updated: Jul 26, 2025

Split Strings by Separator

November 29, 2024 · 4 min · array · leetcode · string · Last updated: Jul 26, 2025

Split the Array

November 29, 2024 · 3 min · array · counting · hash-table · leetcode · Last updated: Jul 26, 2025

Stamping the Grid

November 29, 2024 · 8 min · array · greedy · leetcode · matrix · prefix-sum · Last updated: Jul 26, 2025

Statistics from a Large Sample

November 29, 2024 · 5 min · array · leetcode · math · probability-and-statistics · Last updated: Jul 26, 2025

Status of Flight Tickets

November 29, 2024 · 4 min · leetcode · Last updated: Aug 2, 2025

Stone Game VI

November 29, 2024 · 6 min · array · game-theory · greedy · heap-priority-queue · leetcode · math · sorting · Last updated: Aug 2, 2025

Stone Game VIII

November 29, 2024 · 5 min · array · dynamic-programming · game-theory · leetcode · math · prefix-sum · Last updated: Aug 2, 2025

Stone Removal Game

November 29, 2024 · 3 min · leetcode · math · simulation · Last updated: Aug 2, 2025

Strange Printer II

November 29, 2024 · 9 min · array · graph · leetcode · matrix · topological-sort · Last updated: Aug 2, 2025

String Transformation

November 29, 2024 · 9 min · dynamic-programming · leetcode · math · string · string-matching · Last updated: Aug 2, 2025

String Without AAA or BBB

November 29, 2024 · 5 min · greedy · leetcode · string · Last updated: Aug 2, 2025

Subarrays Distinct Element Sum of Squares II

November 29, 2024 · 5 min · array · binary-indexed-tree · dynamic-programming · leetcode · segment-tree · Last updated: Aug 2, 2025

Subsequence of Size K With the Largest Even Sum

November 29, 2024 · 7 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Subsequence With the Minimum Score

November 29, 2024 · 2 min · binary-search · leetcode · string · two-pointers · Last updated: Aug 2, 2025

Subtract the Product and Sum of Digits of an Integer

November 29, 2024 · 3 min · leetcode · math · Last updated: Aug 2, 2025

Sum Game

November 29, 2024 · 6 min · game-theory · greedy · leetcode · math · string · Last updated: Aug 2, 2025

Sum in a Matrix

November 29, 2024 · 4 min · array · heap-priority-queue · leetcode · matrix · simulation · sorting · Last updated: Aug 2, 2025

Sum of Beauty in the Array

November 29, 2024 · 6 min · array · leetcode · Last updated: Aug 2, 2025

Sum of Consecutive Subsequences

November 29, 2024 · 6 min · array · dynamic-programming · hash-table · leetcode · Last updated: Aug 2, 2025

Sum of Digit Differences of All Pairs

November 29, 2024 · 6 min · array · counting · hash-table · leetcode · math · Last updated: Aug 2, 2025

Sum of Digits in the Minimum Number

November 29, 2024 · 3 min · array · leetcode · math · Last updated: Aug 2, 2025

Sum of Good Subsequences

November 29, 2024 · 5 min · array · dynamic-programming · hash-table · leetcode · Last updated: Aug 2, 2025

Sum of Mutated Array Closest to Target

November 29, 2024 · 5 min · array · binary-search · leetcode · sorting · Last updated: Aug 2, 2025

Sum of Number and Its Reverse

November 29, 2024 · 3 min · enumeration · leetcode · math · Last updated: Aug 2, 2025

Sum of Remoteness of All Cells

November 29, 2024 · 9 min · array · breadth-first-search · depth-first-search · hash-table · leetcode · matrix · union-find · Last updated: Aug 2, 2025

Sum of Subarray Ranges

November 29, 2024 · 7 min · array · leetcode · monotonic-stack · stack · Last updated: Aug 2, 2025

Sum of Total Strength of Wizards

November 29, 2024 · 9 min · array · leetcode · monotonic-stack · prefix-sum · stack · Last updated: Aug 2, 2025

Sum of Values at Indices With K Set Bits

November 29, 2024 · 3 min · array · bit-manipulation · leetcode · Last updated: Aug 2, 2025

Suspicious Bank Accounts

November 29, 2024 · 6 min · database · leetcode · Last updated: Aug 2, 2025

Swap Adjacent in LR String

November 29, 2024 · 5 min · leetcode · string · two-pointers · Last updated: Aug 2, 2025

Symmetric Coordinates

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Tag Validator

November 29, 2024 · 8 min · leetcode · stack · string · Last updated: Aug 2, 2025

Taking Maximum Energy From the Mystic Dungeon

November 29, 2024 · 4 min · array · leetcode · prefix-sum · Last updated: Aug 2, 2025

Teemo Attacking

November 29, 2024 · 4 min · array · leetcode · simulation · Last updated: Aug 2, 2025

The Dining Philosophers

November 29, 2024 · 4 min · concurrency · leetcode · Last updated: Aug 2, 2025

The Employee That Worked on the Longest Task

November 29, 2024 · 4 min · array · leetcode · Last updated: Aug 2, 2025

The k Strongest Values in an Array

November 29, 2024 · 4 min · array · leetcode · sorting · two-pointers · Last updated: Aug 2, 2025

The K Weakest Rows in a Matrix

November 29, 2024 · 3 min · array · binary-search · heap-priority-queue · leetcode · matrix · sorting · Last updated: Aug 2, 2025

The Latest Time to Catch a Bus

November 29, 2024 · 6 min · array · binary-search · leetcode · sorting · two-pointers · Last updated: Aug 2, 2025

The Most Frequently Ordered Products for Each Customer

November 29, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

The Most Recent Three Orders

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

The Number of Employees Which Report to Each Employee

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

The Number of Full Rounds You Have Played

November 29, 2024 · 4 min · leetcode · math · string · Last updated: Aug 2, 2025

The Number of Good Subsets

November 29, 2024 · 8 min · array · bit-manipulation · bitmask · dynamic-programming · leetcode · math · Last updated: Aug 2, 2025

The Score of Students Solving Math Expression

November 29, 2024 · 9 min · array · dynamic-programming · leetcode · math · memoization · stack · string · Last updated: Aug 2, 2025

The Wording Game

November 29, 2024 · 7 min · array · game-theory · greedy · leetcode · math · string · two-pointers · Last updated: Aug 2, 2025

Three Divisors

November 29, 2024 · 3 min · enumeration · leetcode · math · number-theory · Last updated: Aug 2, 2025

Three Equal Parts

November 29, 2024 · 5 min · array · leetcode · math · Last updated: Aug 2, 2025

Throttle

November 29, 2024 · 5 min · leetcode · Last updated: Aug 2, 2025

Time Needed to Buy Tickets

November 29, 2024 · 3 min · array · leetcode · queue · simulation · Last updated: Aug 2, 2025

Time to Cross a Bridge

November 29, 2024 · 5 min · array · heap-priority-queue · leetcode · simulation · Last updated: Aug 2, 2025

To Be Or Not To Be

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

To Lower Case

November 29, 2024 · 1 min · leetcode · string · Last updated: Aug 2, 2025

Top Percentile Fraud

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Total Cost to Hire K Workers

November 29, 2024 · 7 min · array · heap-priority-queue · leetcode · simulation · todo · two-pointers · Last updated: Aug 2, 2025

Total Distance Traveled

November 29, 2024 · 3 min · leetcode · math · simulation · Last updated: Aug 2, 2025

Total Traveled Distance

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Tournament Winners

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Traffic Light Controlled Intersection

November 29, 2024 · 5 min · concurrency · leetcode · Last updated: Aug 2, 2025

Tree Node Leetcode Database Problem

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Truncate Sentence

November 29, 2024 · 2 min · array · leetcode · string · Last updated: Aug 2, 2025

Tweet Counts Per Frequency

November 29, 2024 · 4 min · binary-search · design · hash-table · leetcode · ordered-set · sorting · Last updated: Aug 2, 2025

Two Out of Three

November 29, 2024 · 2 min · array · bit-manipulation · hash-table · leetcode · Last updated: Aug 2, 2025

Uncrossed Lines

November 29, 2024 · 2 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Undefined to Null

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Unique Number of Occurrences

November 29, 2024 · 2 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

Unique Substrings With Equal Digit Frequency

November 29, 2024 · 2 min · counting · hash-function · hash-table · leetcode · rolling-hash · string · Last updated: Aug 2, 2025

Unpopular Books

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

User Activity for the Past 30 Days I

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

User Purchase Platform

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Users That Actively Request Confirmation Messages

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Users With Two Purchases Within Seven Days

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Valid Palindrome 3 - Is string palindrome after deleting at most k chars

November 29, 2024 · 3 min · dynamic-programming · leetcode · palindrome · string · two-pointers · Last updated: Aug 2, 2025

Vowel Spellchecker

November 29, 2024 · 7 min · array · hash-table · leetcode · string · Last updated: Jul 26, 2025

Vowels Game in a String

November 29, 2024 · 4 min · brainteaser · game-theory · leetcode · math · string · Last updated: Aug 2, 2025

Vowels of All Substrings

November 29, 2024 · 4 min · combinatorics · dynamic-programming · leetcode · math · string · Last updated: Aug 2, 2025

Water Bottles II

November 29, 2024 · 3 min · leetcode · math · simulation · Last updated: Aug 2, 2025

Watering Plants

November 29, 2024 · 5 min · array · leetcode · simulation · Last updated: Aug 2, 2025

Ways to Express an Integer as Sum of Powers

November 29, 2024 · 5 min · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Web Crawler

November 29, 2024 · 7 min · breadth-first-search · depth-first-search · interactive · leetcode · string · Last updated: Aug 2, 2025

Web Crawler Multithreaded

November 29, 2024 · 5 min · breadth-first-search · concurrency · depth-first-search · leetcode · Last updated: Aug 2, 2025

Widest Vertical Area Between Two Points Containing No Points

November 29, 2024 · 3 min · array · leetcode · sorting · Last updated: Aug 2, 2025

Winner of the Linked List Game

November 29, 2024 · 6 min · leetcode · linked-list · Last updated: Aug 2, 2025

Word Abbreviation

November 29, 2024 · 7 min · array · greedy · leetcode · sorting · string · trie · Last updated: Aug 2, 2025

X of a Kind in a Deck of Cards

November 29, 2024 · 4 min · array · counting · hash-table · leetcode · math · number-theory · Last updated: Aug 2, 2025

Year on Year Growth Rate

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Add Two Promises

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Append K Integers With Minimal Sum

November 29, 2024 · 5 min · array · greedy · leetcode · math · sorting · Last updated: Aug 2, 2025

Apple Redistribution into Boxes

November 29, 2024 · 3 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Apply Operations to Make Sum of Array Greater Than or Equal to k

November 29, 2024 · 3 min · enumeration · greedy · leetcode · math · Last updated: Aug 2, 2025

Apply Operations to Make Two Strings Equal

November 29, 2024 · 4 min · dynamic-programming · leetcode · string · Last updated: Aug 2, 2025

Apply Operations to Maximize Frequency Score

November 29, 2024 · 4 min · array · binary-search · leetcode · prefix-sum · sliding-window · sorting · Last updated: Aug 2, 2025

Arithmetic Subarrays

November 29, 2024 · 4 min · array · hash-table · leetcode · sorting · Last updated: Aug 2, 2025

Array Nesting

November 29, 2024 · 3 min · array · depth-first-search · leetcode · Last updated: Aug 2, 2025

Array Partition

November 29, 2024 · 3 min · array · counting-sort · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Array Prototype Last

November 29, 2024 · 1 min · leetcode · Last updated: Aug 2, 2025

Array Reduce Transformation

November 29, 2024 · 4 min · leetcode · Last updated: Aug 10, 2025

Average of Levels in Binary Tree

November 29, 2024 · 4 min · binary-tree · breadth-first-search · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Average Salary Excluding the Minimum and Maximum Salary

November 29, 2024 · 3 min · array · leetcode · sorting · Last updated: Aug 2, 2025

Average Value of Even Numbers That Are Divisible by Three

November 29, 2024 · 3 min · array · leetcode · math · Last updated: Aug 2, 2025

Bank Account Summary II

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Beautiful Arrangement

November 29, 2024 · 5 min · array · backtracking · bit-manipulation · bitmask · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Beautiful Arrangement II

November 29, 2024 · 5 min · array · leetcode · math · Last updated: Aug 2, 2025

Beautiful Array

November 29, 2024 · 4 min · array · divide-and-conquer · leetcode · math · Last updated: Aug 2, 2025

Beautiful Towers I

November 29, 2024 · 6 min · array · leetcode · monotonic-stack · stack · Last updated: Aug 2, 2025

Best Poker Hand

November 29, 2024 · 5 min · array · counting · hash-table · leetcode · Last updated: Aug 2, 2025

Binary Prefix Divisible By 5

November 29, 2024 · 3 min · array · bit-manipulation · leetcode · Last updated: Aug 2, 2025

Binary String With Substrings Representing 1 To N

November 29, 2024 · 3 min · leetcode · string · Last updated: Aug 2, 2025

Binary Subarrays With Sum

November 29, 2024 · 3 min · array · hash-table · leetcode · prefix-sum · sliding-window · Last updated: Aug 2, 2025

Binary Tree Coloring Game

November 29, 2024 · 6 min · binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Binary Tree Tilt

November 29, 2024 · 5 min · binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Booking Concert Tickets in Groups

November 29, 2024 · 6 min · binary-indexed-tree · binary-search · design · leetcode · segment-tree · Last updated: Aug 2, 2025

Brace Expansion II

November 29, 2024 · 7 min · backtracking · breadth-first-search · leetcode · stack · string · Last updated: Aug 2, 2025

Build an Array With Stack Operations

November 29, 2024 · 5 min · array · leetcode · simulation · stack · Last updated: Aug 2, 2025

Building Boxes

November 29, 2024 · 4 min · binary-search · greedy · leetcode · math · Last updated: Aug 2, 2025

Buy Two Chocolates

November 29, 2024 · 2 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Calculate Amount Paid in Taxes

November 29, 2024 · 3 min · array · leetcode · simulation · Last updated: Jul 1, 2025

Calculate Delayed Arrival Time

November 29, 2024 · 2 min · leetcode · math · Last updated: Aug 2, 2025

Calculate Digit Sum of a String

November 29, 2024 · 6 min · leetcode · simulation · string · Last updated: Jul 1, 2025

Call Function with Custom Context

November 29, 2024 · 3 min · leetcode · Last updated: Jul 1, 2025

Can You Eat Your Favorite Candy on Your Favorite Day?

November 29, 2024 · 6 min · array · leetcode · prefix-sum · Last updated: Jul 1, 2025

Car Fleet II

November 29, 2024 · 7 min · array · heap-priority-queue · leetcode · math · monotonic-stack · stack · Last updated: Jul 1, 2025

Cat and Mouse

November 29, 2024 · 10 min · dynamic-programming · game-theory · graph · leetcode · math · memoization · topological-sort · Last updated: Jul 1, 2025

Cat and Mouse II

November 29, 2024 · 13 min · array · dynamic-programming · game-theory · graph · leetcode · math · matrix · memoization · topological-sort · Last updated: Jul 1, 2025

Cells in a Range on an Excel Sheet

November 29, 2024 · 4 min · leetcode · string · Last updated: Jul 1, 2025

Chalkboard XOR Game

November 29, 2024 · 3 min · array · bit-manipulation · brainteaser · game-theory · leetcode · math · Last updated: Jul 1, 2025

Change Data Type

November 29, 2024 · 2 min · leetcode · Last updated: Jul 1, 2025

Change Minimum Characters to Satisfy One of Three Conditions

November 29, 2024 · 4 min · counting · hash-table · leetcode · prefix-sum · string · Last updated: Jul 1, 2025

Check Array Formation Through Concatenation

November 29, 2024 · 4 min · array · hash-table · leetcode · Last updated: Jul 1, 2025

Check Balanced String

November 29, 2024 · 2 min · leetcode · string · Last updated: Jul 1, 2025

Check Distances Between Same Letters

November 29, 2024 · 3 min · array · hash-table · leetcode · string · Last updated: Jul 3, 2025

Check if a String Is an Acronym of Words

November 29, 2024 · 2 min · array · leetcode · string · Last updated: Jul 3, 2025

Check If a Word Occurs As a Prefix of Any Word in a Sentence

November 29, 2024 · 7 min · leetcode · string · string-matching · two-pointers · Last updated: Aug 2, 2025

Check If All 1’s Are at Least Length K Places Away

November 29, 2024 · 3 min · array · leetcode · Last updated: Jul 3, 2025

Check if All A’s Appears Before All B’s

November 29, 2024 · 2 min · leetcode · string · Last updated: Jul 3, 2025

Check if All Characters Have Equal Number of Occurrences

November 29, 2024 · 4 min · counting · hash-table · leetcode · string · Last updated: Jul 3, 2025

Check if All the Integers in a Range Are Covered

November 29, 2024 · 4 min · array · hash-table · leetcode · prefix-sum · Last updated: Aug 2, 2025

Check if an Original String Exists Given Two Encoded Strings

November 29, 2024 · 12 min · dynamic-programming · leetcode · string · Last updated: Jul 3, 2025

Check if Array is Good

November 29, 2024 · 5 min · array · hash-table · leetcode · sorting · Last updated: Jul 3, 2025

Check if Grid Satisfies Conditions

November 29, 2024 · 4 min · array · leetcode · matrix · Last updated: Aug 2, 2025

Check If It Is a Good Array

November 29, 2024 · 3 min · array · leetcode · math · number-theory · Last updated: Jul 4, 2025

Check if it is Possible to Split Array

November 29, 2024 · 5 min · array · dynamic-programming · greedy · leetcode · Last updated: Jul 4, 2025

Check if Number Has Equal Digit Count and Digit Value

November 29, 2024 · 4 min · counting · hash-table · leetcode · string · Last updated: Jul 4, 2025

Check if Numbers Are Ascending in a Sentence

November 29, 2024 · 4 min · leetcode · string · Last updated: Jul 4, 2025

Check if Object Instance of Class

November 29, 2024 · 3 min · leetcode · Last updated: Jul 6, 2025

Check if Point Is Reachable

November 29, 2024 · 4 min · leetcode · math · number-theory · Last updated: Jul 4, 2025

Check If String Is a Prefix of Array

November 29, 2024 · 4 min · array · leetcode · string · two-pointers · Last updated: Jul 4, 2025

Check if Strings Can be Made Equal With Operations I

November 29, 2024 · 3 min · leetcode · string · Last updated: Jul 4, 2025

Check if The Number is Fascinating

November 29, 2024 · 3 min · hash-table · leetcode · math · Last updated: Aug 2, 2025

Check if the Rectangle Corner Is Reachable

November 29, 2024 · 8 min · array · breadth-first-search · depth-first-search · geometry · leetcode · math · union-find · Last updated: Jul 6, 2025

Check if There is a Valid Path in a Grid

November 29, 2024 · 7 min · array · breadth-first-search · depth-first-search · leetcode · matrix · union-find · Last updated: Jul 6, 2025

Check if Word Can Be Placed In Crossword

November 29, 2024 · 9 min · array · enumeration · leetcode · matrix · Last updated: Aug 2, 2025

Check Whether Two Strings are Almost Equivalent

November 29, 2024 · 5 min · counting · hash-table · leetcode · string · Last updated: Jul 4, 2025

Cinema Seat Allocation

November 29, 2024 · 6 min · array · bit-manipulation · greedy · hash-table · leetcode · Last updated: Jul 7, 2025

Circular Permutation in Binary Representation

November 29, 2024 · 3 min · backtracking · bit-manipulation · leetcode · math · Last updated: Jul 6, 2025

Closest Dessert Cost

November 29, 2024 · 7 min · array · backtracking · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Closest Nodes Queries in a Binary Search Tree

November 29, 2024 · 8 min · array · binary-search · binary-search-tree · binary-tree · depth-first-search · leetcode · tree · Last updated: Jul 6, 2025

Closest Subsequence Sum

November 29, 2024 · 9 min · array · bit-manipulation · bitmask · dynamic-programming · leetcode · two-pointers · Last updated: Jul 6, 2025

Coloring A Border

November 29, 2024 · 7 min · array · breadth-first-search · depth-first-search · leetcode · matrix · Last updated: Jul 7, 2025

Compact Object

November 29, 2024 · 3 min · leetcode · Last updated: Jul 7, 2025

Compare Strings by Frequency of the Smallest Character

November 29, 2024 · 6 min · array · binary-search · hash-table · leetcode · sorting · string · Last updated: Jul 7, 2025

Complete Binary Tree Inserter

November 29, 2024 · 6 min · binary-tree · breadth-first-search · design · leetcode · tree · Last updated: Jul 7, 2025

Complex Number Multiplication

November 29, 2024 · 4 min · leetcode · math · simulation · string · Last updated: Jul 7, 2025

Concatenation of Array

November 29, 2024 · 3 min · array · leetcode · simulation · Last updated: Jul 7, 2025

Confirmation Rate

November 29, 2024 · 4 min · database · leetcode · Last updated: Jul 3, 2025

Construct 2D Grid Matching Graph Layout

November 29, 2024 · 11 min · array · graph · hash-table · leetcode · matrix · Last updated: Jul 7, 2025

Construct the Lexicographically Largest Valid Sequence

November 29, 2024 · 5 min · array · backtracking · leetcode · video · Last updated: Aug 2, 2025

Construct the Rectangle

November 29, 2024 · 3 min · leetcode · math · Last updated: Jul 7, 2025

Contiguous Array

November 29, 2024 · 3 min · array · hash-table · leetcode · prefix-sum · Last updated: Aug 2, 2025

Convert Binary Number in a Linked List to Integer

November 29, 2024 · 4 min · leetcode · linked-list · math · Last updated: Jul 7, 2025

Convert Date to Binary

November 29, 2024 · 3 min · leetcode · math · string · Last updated: Jul 7, 2025

Convert Integer to the Sum of Two No-Zero Integers

November 29, 2024 · 3 min · leetcode · math · Last updated: Aug 2, 2025

Coordinate With Maximum Network Quality

November 29, 2024 · 9 min · array · enumeration · leetcode · Last updated: Aug 2, 2025

Corporate Flight Bookings

November 29, 2024 · 4 min · array · leetcode · prefix-sum · Last updated: Aug 2, 2025

Count Almost Equal Pairs I

November 29, 2024 · 6 min · array · counting · enumeration · hash-table · leetcode · sorting · Last updated: Aug 2, 2025

Count Alternating Subarrays

November 29, 2024 · 4 min · array · leetcode · math · Last updated: Aug 2, 2025

Count Array Pairs Divisible by K

November 29, 2024 · 5 min · array · leetcode · math · number-theory · Last updated: Aug 2, 2025

Count Asterisks

November 29, 2024 · 4 min · leetcode · string · Last updated: Aug 2, 2025

Count Beautiful Substrings I

November 29, 2024 · 8 min · enumeration · hash-table · leetcode · math · number-theory · prefix-sum · string · Last updated: Aug 2, 2025

Count Beautiful Substrings II

November 29, 2024 · 7 min · hash-table · leetcode · math · number-theory · prefix-sum · string · Last updated: Aug 2, 2025

Count Binary Substrings

November 29, 2024 · 4 min · leetcode · string · two-pointers · Last updated: Aug 2, 2025

Count Collisions of Monkeys on a Polygon

November 29, 2024 · 5 min · leetcode · math · recursion · Last updated: Aug 2, 2025

Count Days Spent Together

November 29, 2024 · 5 min · leetcode · math · string · Last updated: Aug 2, 2025

Count Distinct Numbers on Board

November 29, 2024 · 3 min · array · hash-table · leetcode · math · simulation · Last updated: Aug 2, 2025

Count Elements With Maximum Frequency

November 29, 2024 · 3 min · array · counting · hash-table · leetcode · Last updated: Aug 2, 2025

Count Elements With Strictly Smaller and Greater Elements

November 29, 2024 · 3 min · array · counting · leetcode · sorting · Last updated: Aug 2, 2025

Count Fertile Pyramids in a Land

November 29, 2024 · 10 min · array · dynamic-programming · leetcode · matrix · Last updated: Aug 2, 2025

Count Hills and Valleys in an Array

November 29, 2024 · 8 min · array · leetcode · Last updated: Jul 27, 2025

Count Increasing Quadruplets

November 29, 2024 · 5 min · array · binary-indexed-tree · dynamic-programming · enumeration · leetcode · prefix-sum · Last updated: Aug 2, 2025

Count Integers in Intervals

November 29, 2024 · 5 min · design · leetcode · ordered-set · segment-tree · Last updated: Aug 2, 2025

Count Integers With Even Digit Sum

November 29, 2024 · 4 min · leetcode · math · simulation · Last updated: Aug 2, 2025

Count Items Matching a Rule

November 29, 2024 · 3 min · array · leetcode · string · Last updated: Aug 2, 2025

Count K-Reducible Numbers Less Than N

November 29, 2024 · 5 min · combinatorics · dynamic-programming · leetcode · math · string · Last updated: Aug 2, 2025

Count K-Subsequences of a String With Maximum Beauty

November 29, 2024 · 11 min · combinatorics · greedy · hash-table · leetcode · math · string · Last updated: Aug 2, 2025

Count Nodes Equal to Average of Subtree

November 29, 2024 · 6 min · binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Count Number of Possible Root Nodes

November 29, 2024 · 9 min · array · depth-first-search · dynamic-programming · hash-table · leetcode · tree · Last updated: Aug 2, 2025

Count Number of Special Subsequences

November 29, 2024 · 5 min · array · dynamic-programming · leetcode · Last updated: Jul 26, 2025

Count Number of Texts

November 29, 2024 · 6 min · dynamic-programming · hash-table · leetcode · math · string · Last updated: Jul 26, 2025

Count Number of Ways to Place Houses

November 29, 2024 · 4 min · dynamic-programming · leetcode · Last updated: Jul 26, 2025

Count of Matches in Tournament

November 29, 2024 · 3 min · leetcode · math · simulation · Last updated: Aug 2, 2025

Count of Sub-Multisets With Bounded Sum

November 29, 2024 · 7 min · array · dynamic-programming · hash-table · leetcode · sliding-window · Last updated: Jul 26, 2025

Count of Substrings Containing Every Vowel and K Consonants 2

November 29, 2024 · 5 min · hash-table · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Count Operations to Obtain Zero

November 29, 2024 · 5 min · leetcode · math · simulation · Last updated: Aug 2, 2025

Count Pairs of Connectable Servers in a Weighted Tree Network

November 29, 2024 · 8 min · array · depth-first-search · leetcode · tree · Last updated: Jul 26, 2025

Count Pairs Of Nodes

November 29, 2024 · 8 min · array · binary-search · graph · leetcode · sorting · two-pointers · Last updated: Aug 2, 2025

Count Pairs of Points With Distance k

November 29, 2024 · 5 min · array · bit-manipulation · hash-table · leetcode · Last updated: Aug 2, 2025

Count Pairs That Form a Complete Day I

November 29, 2024 · 4 min · array · counting · hash-table · leetcode · Last updated: Aug 2, 2025

Count Pairs That Form a Complete Day II

November 29, 2024 · 4 min · array · counting · hash-table · leetcode · Last updated: Aug 2, 2025

Count Paths That Can Form a Palindrome in a Tree

November 29, 2024 · 8 min · bit-manipulation · bitmask · depth-first-search · dynamic-programming · leetcode · tree · Last updated: Aug 2, 2025

Count Prefix and Suffix Pairs 2

November 29, 2024 · 6 min · array · hash-function · leetcode · rolling-hash · string · string-matching · trie · Last updated: Aug 2, 2025

Count Special Quadruplets

November 29, 2024 · 4 min · array · enumeration · hash-table · leetcode · Last updated: Aug 2, 2025

Count Stepping Numbers in Range

November 29, 2024 · 5 min · dynamic-programming · leetcode · string · Last updated: Aug 2, 2025

Count Substrings Starting and Ending with Given Character

November 29, 2024 · 3 min · counting · leetcode · math · string · Last updated: Aug 2, 2025

Count Substrings That Differ by One Character

November 29, 2024 · 6 min · dynamic-programming · enumeration · hash-table · leetcode · string · Last updated: Aug 2, 2025

Count Substrings That Satisfy K-Constraint I

November 29, 2024 · 6 min · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Count Subtrees With Max Distance Between Cities

November 29, 2024 · 10 min · bit-manipulation · bitmask · dynamic-programming · enumeration · leetcode · tree · Last updated: Aug 2, 2025

Count Symmetric Integers

November 29, 2024 · 3 min · enumeration · leetcode · math · Last updated: Jul 31, 2025

Count the Number of Houses at a Certain Distance II

November 29, 2024 · 6 min · graph · leetcode · prefix-sum · Last updated: Aug 2, 2025

Count the Number of Incremovable Subarrays I

November 29, 2024 · 3 min · array · binary-search · enumeration · leetcode · two-pointers · Last updated: Aug 2, 2025

Count the Number of Special Characters I

November 29, 2024 · 4 min · hash-table · leetcode · string · Last updated: Aug 2, 2025

Count the Number of Special Characters II

November 29, 2024 · 5 min · hash-table · leetcode · string · Last updated: Aug 2, 2025

Count the Number of Square-Free Subsets

November 29, 2024 · 11 min · array · bit-manipulation · bitmask · dynamic-programming · leetcode · math · Last updated: Aug 2, 2025

Count the Number of Substrings With Dominant Ones

November 29, 2024 · 8 min · enumeration · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Count The Number of Winning Sequences

November 29, 2024 · 11 min · dynamic-programming · leetcode · string · Last updated: Aug 2, 2025

Count Unhappy Friends

November 29, 2024 · 7 min · array · leetcode · simulation · Last updated: Aug 2, 2025

Count Unique Characters of All Substrings of a Given String

November 29, 2024 · 5 min · dynamic-programming · hash-table · leetcode · string · Last updated: Aug 2, 2025

Count Visited Nodes in a Directed Graph

November 29, 2024 · 8 min · dynamic-programming · graph · leetcode · memoization · Last updated: Aug 2, 2025

Count Vowel Substrings of a String

November 29, 2024 · 5 min · hash-table · leetcode · string · Last updated: Aug 2, 2025

Count Words Obtained After Adding a Letter

November 29, 2024 · 7 min · array · bit-manipulation · hash-table · leetcode · sorting · string · Last updated: Aug 2, 2025

Count Zero Request Servers

November 29, 2024 · 8 min · array · hash-table · leetcode · sliding-window · sorting · Last updated: Aug 2, 2025

Counter

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Counter II

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Couples Holding Hands

November 29, 2024 · 6 min · breadth-first-search · depth-first-search · graph · greedy · leetcode · union-find · Last updated: Aug 4, 2025

Course Schedule 4

November 29, 2024 · 4 min · breadth-first-search · depth-first-search · graph · leetcode · topological-sort · Last updated: Aug 2, 2025

Create a DataFrame from List

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Create a New Column

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Create Hello World Function

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Cyclically Rotating a Grid

November 29, 2024 · 8 min · array · leetcode · matrix · simulation · Last updated: Aug 2, 2025

Day of the Week

November 29, 2024 · 5 min · leetcode · math · Last updated: Aug 2, 2025

Decode the Message

November 29, 2024 · 5 min · hash-table · leetcode · string · Last updated: Aug 2, 2025

Decrease Elements To Make Array Zigzag

November 29, 2024 · 5 min · array · greedy · leetcode · Last updated: Aug 2, 2025

Decrypt String from Alphabet to Integer Mapping

November 29, 2024 · 5 min · leetcode · string · Last updated: Aug 2, 2025

Defanging an IP Address

November 29, 2024 · 2 min · leetcode · string · Last updated: Aug 2, 2025

Degree of an Array

November 29, 2024 · 5 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

Delete Columns to Make Sorted II

November 29, 2024 · 6 min · array · greedy · leetcode · string · Last updated: Aug 2, 2025

Delete Duplicate Folders in System

November 29, 2024 · 13 min · array · hash-function · hash-table · leetcode · string · trie · mermaid · mermaid-style-subgraph · Last updated: Jul 20, 2025

Describe the Painting

November 29, 2024 · 5 min · array · hash-table · leetcode · prefix-sum · sorting · Last updated: Aug 2, 2025

Design a Text Editor

November 29, 2024 · 7 min · design · doubly-linked-list · leetcode · linked-list · simulation · stack · string · Last updated: Aug 2, 2025

Design Authentication Manager

November 29, 2024 · 4 min · design · doubly-linked-list · hash-table · leetcode · linked-list · Last updated: Aug 2, 2025

Design Bitset

November 29, 2024 · 5 min · array · design · hash-table · leetcode · string · Last updated: Aug 2, 2025

Design Linked List

November 29, 2024 · 14 min · design · leetcode · linked-list · Last updated: Aug 2, 2025

Design Memory Allocator

November 29, 2024 · 7 min · array · design · hash-table · leetcode · simulation · Last updated: Aug 2, 2025

Design Movie Rental System

November 29, 2024 · 11 min · array · design · hash-table · heap-priority-queue · leetcode · ordered-set · Last updated: Aug 2, 2025

Design Neighbor Sum Service

November 29, 2024 · 9 min · array · design · hash-table · leetcode · matrix · simulation · Last updated: Aug 2, 2025

Destroying Asteroids

November 29, 2024 · 4 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Detect Pattern of Length M Repeated K or More Times

November 29, 2024 · 5 min · array · enumeration · leetcode · Last updated: Aug 2, 2025

Determine the Winner of a Bowling Game

November 29, 2024 · 6 min · array · leetcode · simulation · Last updated: Aug 2, 2025

Determine Whether Matrix Can Be Obtained By Rotation

November 29, 2024 · 5 min · array · leetcode · matrix · Last updated: Aug 2, 2025

Difference Between Element Sum and Digit Sum of an Array

November 29, 2024 · 4 min · array · leetcode · math · Last updated: Aug 2, 2025

Difference of Number of Distinct Values on Diagonals

November 29, 2024 · 9 min · array · hash-table · leetcode · matrix · Last updated: Aug 2, 2025

Distance Between Bus Stops

November 29, 2024 · 3 min · array · leetcode · Last updated: Aug 2, 2025

Distant Barcodes

November 29, 2024 · 5 min · array · counting · greedy · hash-table · heap-priority-queue · leetcode · sorting · Last updated: Aug 2, 2025

Distinct Prime Factors of Product of Array

November 29, 2024 · 6 min · array · hash-table · leetcode · math · number-theory · Last updated: Aug 2, 2025

Distribute Candies to People

November 29, 2024 · 5 min · leetcode · math · simulation · Last updated: Aug 2, 2025

Distribute Elements Into Two Arrays I

November 29, 2024 · 4 min · array · leetcode · simulation · Last updated: Aug 2, 2025

Distribute Elements Into Two Arrays II

November 29, 2024 · 12 min · array · binary-indexed-tree · leetcode · segment-tree · simulation · Last updated: Aug 2, 2025

Dota2 Senate

November 29, 2024 · 6 min · greedy · leetcode · queue · string · Last updated: Aug 2, 2025

Drop Duplicate Rows

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Drop Missing Data

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Earliest Second to Mark Indices II

November 29, 2024 · 4 min · array · binary-search · greedy · heap-priority-queue · leetcode · Last updated: Aug 2, 2025

Element Appearing More Than 25% In Sorted Array

November 29, 2024 · 3 min · array · leetcode · Last updated: Aug 2, 2025

Employee Importance

November 29, 2024 · 5 min · array · breadth-first-search · depth-first-search · hash-table · leetcode · tree · Last updated: Aug 2, 2025

Employees Whose Manager Left the Company

November 29, 2024 · 3 min · database · leetcode · Last updated: Jul 7, 2025

Employees With Missing Information

November 29, 2024 · 3 min · database · leetcode · Last updated: Jul 7, 2025

Encrypt and Decrypt Strings

November 29, 2024 · 11 min · array · design · hash-table · leetcode · string · trie · Last updated: Aug 2, 2025

Equal Rational Numbers

November 29, 2024 · 9 min · leetcode · math · string · Last updated: Aug 2, 2025

Erect the Fence

November 29, 2024 · 6 min · array · geometry · leetcode · math · Last updated: Aug 2, 2025

Escape a Large Maze

November 29, 2024 · 7 min · array · breadth-first-search · depth-first-search · hash-table · leetcode · Last updated: Aug 2, 2025

Escape The Ghosts

November 29, 2024 · 4 min · array · leetcode · math · Last updated: Aug 2, 2025

Exclusive Time of Functions

November 29, 2024 · 8 min · array · leetcode · stack · Last updated: Aug 2, 2025

Existence of a Substring in a String and Its Reverse

November 29, 2024 · 3 min · hash-table · leetcode · string · Last updated: Aug 2, 2025

Fair Distribution of Cookies

November 29, 2024 · 6 min · array · backtracking · bit-manipulation · bitmask · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Filter Restaurants by Vegan-Friendly, Price and Distance

November 29, 2024 · 5 min · array · leetcode · sorting · Last updated: Aug 2, 2025

Final Array State After K Multiplication Operations 2

November 29, 2024 · 10 min · array · heap-priority-queue · leetcode · simulation · Last updated: Aug 2, 2025

Find a Good Subset of the Matrix

November 29, 2024 · 7 min · array · bit-manipulation · hash-table · leetcode · matrix · Last updated: Aug 2, 2025

Find a Safe Walk Through a Grid

November 29, 2024 · 8 min · array · breadth-first-search · graph · heap-priority-queue · leetcode · matrix · shortest-path · Last updated: Aug 2, 2025

Find All Good Indices

November 29, 2024 · 6 min · array · dynamic-programming · leetcode · prefix-sum · Last updated: Aug 2, 2025

Find All Lonely Numbers in the Array

November 29, 2024 · 4 min · array · counting · hash-table · leetcode · Last updated: Aug 2, 2025

Find All People With Secret

November 29, 2024 · 10 min · breadth-first-search · depth-first-search · graph · leetcode · sorting · union-find · Last updated: Aug 2, 2025

Find All Possible Stable Binary Arrays I

November 29, 2024 · 9 min · dynamic-programming · leetcode · prefix-sum · Last updated: Aug 2, 2025

Find All Possible Stable Binary Arrays II

November 29, 2024 · 9 min · dynamic-programming · leetcode · prefix-sum · Last updated: Aug 2, 2025

Find Beautiful Indices in the Given Array I

November 29, 2024 · 6 min · binary-search · hash-function · leetcode · rolling-hash · string · string-matching · two-pointers · Last updated: Aug 2, 2025

Find Beautiful Indices in the Given Array II

November 29, 2024 · 6 min · binary-search · hash-function · leetcode · rolling-hash · string · string-matching · two-pointers · Last updated: Aug 2, 2025

Find Elements in a Contaminated Binary Tree

November 29, 2024 · 4 min · binary-tree · breadth-first-search · depth-first-search · design · hash-table · leetcode · tree · video · Last updated: Aug 2, 2025

Find Greatest Common Divisor of Array

November 29, 2024 · 4 min · array · leetcode · math · number-theory · Last updated: Aug 2, 2025

Find if Digit Game Can Be Won

November 29, 2024 · 4 min · array · leetcode · math · Last updated: Aug 2, 2025

Find Indices of Stable Mountains

November 29, 2024 · 3 min · array · leetcode · Last updated: Aug 2, 2025

Find Indices With Index and Value Difference I

November 29, 2024 · 5 min · array · leetcode · two-pointers · Last updated: Aug 2, 2025

Find Indices With Index and Value Difference II

November 29, 2024 · 7 min · array · leetcode · two-pointers · Last updated: Aug 2, 2025

Find Maximum Number of String Pairs

November 29, 2024 · 5 min · array · hash-table · leetcode · simulation · string · Last updated: Aug 2, 2025

Find Minimum Operations to Make All Elements Divisible by Three

November 29, 2024 · 3 min · array · leetcode · math · Last updated: Aug 2, 2025

Find Number of Ways to Reach the K-th Stair

November 29, 2024 · 7 min · bit-manipulation · combinatorics · dynamic-programming · leetcode · math · memoization · Last updated: Aug 2, 2025

Find Occurrences of an Element in an Array

November 29, 2024 · 4 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

Find Palindrome With Fixed Length

November 29, 2024 · 5 min · array · leetcode · math · Last updated: Aug 2, 2025

Find Products of Elements of Big Array

November 29, 2024 · 11 min · array · binary-search · bit-manipulation · leetcode · Last updated: Aug 2, 2025

Find Servers That Handled Most Number of Requests

November 29, 2024 · 8 min · array · greedy · heap-priority-queue · leetcode · ordered-set · Last updated: Aug 2, 2025

Find Subarray With Bitwise OR Closest to K

November 29, 2024 · 5 min · array · binary-search · bit-manipulation · leetcode · segment-tree · Last updated: Aug 2, 2025

Find Subarrays With Equal Sum

November 29, 2024 · 4 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

Find Substring With Given Hash Value

November 29, 2024 · 7 min · hash-function · leetcode · rolling-hash · sliding-window · string · Last updated: Aug 2, 2025

Find Subtree Sizes After Changes

November 29, 2024 · 8 min · array · depth-first-search · hash-table · leetcode · string · tree · Last updated: Aug 2, 2025

Find Target Indices After Sorting Array

November 29, 2024 · 3 min · array · binary-search · leetcode · sorting · Last updated: Aug 2, 2025

Find the Array Concatenation Value

November 29, 2024 · 5 min · array · leetcode · simulation · two-pointers · Last updated: Aug 2, 2025

Find the Distance Value Between Two Arrays

November 29, 2024 · 5 min · array · binary-search · leetcode · sorting · two-pointers · Last updated: Aug 2, 2025

Find the Distinct Difference Array

November 29, 2024 · 6 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

Find the Divisibility Array of a String

November 29, 2024 · 4 min · array · leetcode · math · string · Last updated: Aug 2, 2025

Find The First Player to win K Games in a Row

November 29, 2024 · 7 min · array · leetcode · simulation · Last updated: Aug 2, 2025

Find the Integer Added to Array I

November 29, 2024 · 3 min · array · leetcode · Last updated: Aug 2, 2025

Find the K-Beauty of a Number

November 29, 2024 · 4 min · leetcode · math · sliding-window · string · Last updated: Aug 2, 2025

Find the K-or of an Array

November 29, 2024 · 5 min · array · bit-manipulation · leetcode · Last updated: Aug 2, 2025

Find the K-Sum of an Array

November 29, 2024 · 6 min · array · heap-priority-queue · leetcode · sorting · Last updated: Aug 2, 2025

Find the K-th Character in String Game I

November 29, 2024 · 5 min · bit-manipulation · leetcode · math · recursion · simulation · Last updated: Aug 2, 2025

Find the K-th Character in String Game II

November 29, 2024 · 6 min · bit-manipulation · leetcode · math · recursion · Last updated: Aug 2, 2025

Find the Largest Area of Square Inside Two Rectangles

November 29, 2024 · 7 min · array · geometry · leetcode · math · Last updated: Aug 2, 2025

Find the Largest Palindrome Divisible by K

November 29, 2024 · 5 min · dynamic-programming · greedy · leetcode · math · number-theory · string · Last updated: Aug 2, 2025

Find the Longest Balanced Substring of a Binary String

November 29, 2024 · 4 min · leetcode · string · Last updated: Aug 2, 2025

Find the Maximum Achievable Number

November 29, 2024 · 2 min · leetcode · math · Last updated: Aug 2, 2025

Find the Maximum Divisibility Score

November 29, 2024 · 5 min · array · leetcode · Last updated: Aug 2, 2025

Find the Maximum Factor Score of Array

November 29, 2024 · 7 min · array · leetcode · math · number-theory · Last updated: Aug 2, 2025

Find the Maximum Length of a Good Subsequence I

November 29, 2024 · 6 min · array · dynamic-programming · hash-table · leetcode · Last updated: Aug 2, 2025

Find the Maximum Length of a Good Subsequence II

November 29, 2024 · 5 min · array · dynamic-programming · hash-table · leetcode · Last updated: Aug 2, 2025

Find the Maximum Number of Fruits Collected

November 29, 2024 · 14 min · array · dynamic-programming · leetcode · matrix · Last updated: Aug 7, 2025

Find the Maximum Number of Marked Indices

November 29, 2024 · 5 min · array · binary-search · greedy · leetcode · sorting · two-pointers · Last updated: Aug 2, 2025

Find the Maximum Sequence Value of Array

November 29, 2024 · 3 min · array · bit-manipulation · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Find the Median of the Uniqueness Array

November 29, 2024 · 7 min · array · binary-search · hash-table · leetcode · sliding-window · Last updated: Aug 2, 2025

Find the Minimum Area to Cover All Ones I

November 29, 2024 · 5 min · array · leetcode · matrix · Last updated: Aug 2, 2025

Find the Minimum Number of Fibonacci Numbers Whose Sum Is K

November 29, 2024 · 4 min · greedy · leetcode · math · Last updated: Aug 2, 2025

Find the Minimum Possible Sum of a Beautiful Array

November 29, 2024 · 4 min · greedy · leetcode · math · Last updated: Aug 2, 2025

Find the Most Competitive Subsequence

November 29, 2024 · 4 min · array · greedy · leetcode · monotonic-stack · stack · Last updated: Aug 2, 2025

Find the N-th Value After K Seconds

November 29, 2024 · 4 min · array · combinatorics · leetcode · math · prefix-sum · simulation · Last updated: Aug 2, 2025

Find the Number of Good Pairs II

November 29, 2024 · 6 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

Find the Number of Possible Ways for an Event

November 29, 2024 · 11 min · combinatorics · dynamic-programming · leetcode · math · Last updated: Aug 2, 2025

Find the Number of Subarrays Where Boundary Elements Are Maximum

November 29, 2024 · 9 min · array · binary-search · leetcode · monotonic-stack · stack · Last updated: Aug 2, 2025

Find the Number of Subsequences With Equal GCD

November 29, 2024 · 9 min · array · dynamic-programming · leetcode · math · number-theory · Last updated: Aug 2, 2025

Find the Occurrence of First Almost Equal Substring

November 29, 2024 · 5 min · leetcode · string · string-matching · Last updated: Aug 2, 2025

Find The Original Array of Prefix Xor

November 29, 2024 · 3 min · array · bit-manipulation · leetcode · Last updated: Aug 2, 2025

Find the Original Typed String I

November 29, 2024 · 7 min · leetcode · string · Last updated: Aug 2, 2025

Find the Peaks

November 29, 2024 · 4 min · array · enumeration · leetcode · Last updated: Aug 2, 2025

Find the Pivot Integer

November 29, 2024 · 3 min · leetcode · math · prefix-sum · Last updated: Aug 2, 2025

Find the Power of K-Size Subarrays II

November 29, 2024 · 6 min · array · leetcode · sliding-window · Last updated: Aug 2, 2025

Find the Score of All Prefixes of an Array

November 29, 2024 · 5 min · array · leetcode · prefix-sum · Last updated: Aug 2, 2025

Find the Substring With Maximum Cost

November 29, 2024 · 5 min · array · dynamic-programming · hash-table · leetcode · string · Last updated: Jul 26, 2025

Find the Sum of Subsequence Powers

November 29, 2024 · 7 min · array · dynamic-programming · leetcode · sorting · Last updated: Aug 2, 2025

Find the Sum of the Power of All Subsequences

November 29, 2024 · 5 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Find the Value of the Partition

November 29, 2024 · 4 min · array · leetcode · sorting · Last updated: Aug 2, 2025

Find the Width of Columns of a Grid

November 29, 2024 · 4 min · array · leetcode · matrix · Last updated: Aug 2, 2025

Find the Winning Player in Coin Game

November 29, 2024 · 4 min · game-theory · leetcode · math · simulation · Last updated: Aug 2, 2025

Find the XOR of Numbers Which Appear Twice

November 29, 2024 · 3 min · array · bit-manipulation · hash-table · leetcode · Last updated: Aug 2, 2025

Find Three Consecutive Integers That Sum to a Given Number

November 29, 2024 · 3 min · leetcode · math · simulation · Last updated: Aug 2, 2025

Find Triangular Sum of an Array

November 29, 2024 · 3 min · array · combinatorics · leetcode · math · simulation · Last updated: Aug 2, 2025

Find Two Non-overlapping Sub-arrays Each With Target Sum

November 29, 2024 · 6 min · array · binary-search · dynamic-programming · hash-table · leetcode · sliding-window · Last updated: Aug 2, 2025

Find Words That Can Be Formed by Characters

November 29, 2024 · 5 min · array · counting · hash-table · leetcode · string · Last updated: Aug 2, 2025

Find X-Sum of All K-Long Subarrays II

November 29, 2024 · 4 min · array · hash-table · heap-priority-queue · leetcode · sliding-window · Last updated: Aug 2, 2025

Find XOR Sum of All Pairs Bitwise AND

November 29, 2024 · 4 min · array · bit-manipulation · leetcode · math · Last updated: Aug 2, 2025

Finding Pairs With a Certain Sum

November 29, 2024 · 6 min · array · design · hash-table · leetcode · Last updated: Jul 6, 2025

Finding the Users Active Minutes

November 29, 2024 · 5 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

First Day Where You Have Been in All the Rooms

November 29, 2024 · 5 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Flipping an Image

November 29, 2024 · 4 min · array · bit-manipulation · leetcode · matrix · simulation · two-pointers · Last updated: Aug 2, 2025

Form Array by Concatenating Subarrays of Another Array

November 29, 2024 · 6 min · array · greedy · leetcode · string-matching · two-pointers · Last updated: Aug 2, 2025

Friends Of Appropriate Ages

November 29, 2024 · 6 min · array · binary-search · leetcode · sorting · two-pointers · Last updated: Aug 2, 2025

Frog Position After T Seconds

November 29, 2024 · 7 min · breadth-first-search · depth-first-search · graph · leetcode · tree · Last updated: Aug 2, 2025

Function Composition

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Generate a String With Characters That Have Odd Counts

November 29, 2024 · 3 min · leetcode · string · Last updated: Aug 2, 2025

Generate Binary Strings Without Adjacent Zeros

November 29, 2024 · 4 min · backtracking · bit-manipulation · leetcode · string · Last updated: Aug 2, 2025

Get Biggest Three Rhombus Sums in a Grid

November 29, 2024 · 7 min · array · heap-priority-queue · leetcode · math · matrix · prefix-sum · sorting · Last updated: Aug 2, 2025

Get Watched Videos by Your Friends

November 29, 2024 · 8 min · array · breadth-first-search · graph · hash-table · leetcode · sorting · Last updated: Aug 2, 2025

Greatest Common Divisor Traversal

November 29, 2024 · 9 min · array · leetcode · math · number-theory · union-find · Last updated: Aug 2, 2025

Greatest English Letter in Upper and Lower Case

November 29, 2024 · 4 min · enumeration · hash-table · leetcode · string · Last updated: Aug 2, 2025

Groups of Special-Equivalent Strings

November 29, 2024 · 5 min · array · hash-table · leetcode · sorting · string · Last updated: Aug 2, 2025

Groups of Strings

November 29, 2024 · 12 min · bit-manipulation · leetcode · string · union-find · Last updated: Aug 2, 2025

Guess the Word

November 29, 2024 · 8 min · array · game-theory · interactive · leetcode · math · string · Last updated: Aug 2, 2025

Handling Sum Queries After Update

November 29, 2024 · 15 min · array · leetcode · segment-tree · Last updated: Aug 2, 2025

Hash Divided String

November 29, 2024 · 5 min · leetcode · simulation · string · Last updated: Aug 2, 2025

How Many Numbers Are Smaller Than the Current Number

November 29, 2024 · 4 min · array · counting · hash-table · leetcode · sorting · Last updated: Jul 26, 2025

HTML Entity Parser

November 29, 2024 · 4 min · hash-table · leetcode · string · Last updated: Jul 26, 2025

Image Smoother

November 29, 2024 · 7 min · array · leetcode · matrix · Last updated: Jul 26, 2025

Immediate Food Delivery II

November 29, 2024 · 2 min · database · leetcode · Last updated: Aug 2, 2025

Incremental Memory Leak

November 29, 2024 · 6 min · leetcode · math · simulation · Last updated: Aug 2, 2025

Interval Cancellation

November 29, 2024 · 4 min · leetcode · Last updated: Aug 2, 2025

Interval List Intersections

November 29, 2024 · 4 min · array · interval · interviewbit · leetcode · two-pointers · Last updated: Aug 2, 2025

Invalid Transactions

November 29, 2024 · 8 min · array · hash-table · leetcode · sorting · string · Last updated: Aug 2, 2025

Join Two Arrays by ID

November 29, 2024 · 4 min · leetcode · Last updated: Aug 2, 2025

Jump Game 5

November 29, 2024 · 7 min · array · dynamic-programming · leetcode · sorting · Last updated: Aug 2, 2025

K Divisible Elements Subarrays

November 29, 2024 · 5 min · array · enumeration · hash-function · hash-table · leetcode · rolling-hash · trie · Last updated: Aug 2, 2025

K-th Largest Perfect Subtree Size in Binary Tree

November 29, 2024 · 6 min · binary-tree · depth-first-search · leetcode · sorting · tree · Last updated: Aug 2, 2025

K-th Symbol in Grammar

November 29, 2024 · 3 min · bit-manipulation · leetcode · math · recursion · Last updated: Aug 2, 2025

Keyboard Row

November 29, 2024 · 5 min · array · hash-table · leetcode · string · Last updated: Aug 2, 2025

Largest 1-Bordered Square

November 29, 2024 · 7 min · array · dynamic-programming · leetcode · matrix · Last updated: Aug 2, 2025

Largest Component Size by Common Factor

November 29, 2024 · 6 min · array · hash-table · leetcode · math · number-theory · union-find · Last updated: Aug 2, 2025

Largest Merge Of Two Strings

November 29, 2024 · 5 min · greedy · leetcode · string · two-pointers · Last updated: Aug 2, 2025

Largest Palindromic Number

November 29, 2024 · 6 min · counting · greedy · hash-table · leetcode · string · Last updated: Aug 2, 2025

Largest Perimeter Triangle

November 29, 2024 · 3 min · array · greedy · leetcode · math · sorting · Last updated: Aug 2, 2025

Last Substring in Lexicographical Order

November 29, 2024 · 5 min · leetcode · string · two-pointers · Last updated: Aug 2, 2025

Last Visited Integers

November 29, 2024 · 6 min · array · leetcode · simulation · Last updated: Aug 2, 2025

Latest Time You Can Obtain After Replacing Characters

November 29, 2024 · 5 min · enumeration · leetcode · string · Last updated: Aug 2, 2025

Left and Right Sum Differences

November 29, 2024 · 4 min · array · leetcode · prefix-sum · Last updated: Aug 2, 2025

Length of Longest Subarray With at Most K Frequency

November 29, 2024 · 5 min · array · hash-table · leetcode · sliding-window · Last updated: Aug 2, 2025

Length of the Longest Subsequence That Sums to Target

November 29, 2024 · 5 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Lexicographically Smallest Palindrome

November 29, 2024 · 4 min · greedy · leetcode · string · two-pointers · Last updated: Aug 2, 2025

Lexicographically Smallest String After a Swap

November 29, 2024 · 4 min · greedy · leetcode · string · Last updated: Aug 2, 2025

Lexicographically Smallest String After Operations With Constraint

November 29, 2024 · 5 min · greedy · leetcode · string · Last updated: Aug 2, 2025

Linked List Components

November 29, 2024 · 4 min · array · hash-table · leetcode · linked-list · Last updated: Aug 2, 2025

List the Products Ordered in a Period

November 29, 2024 · 4 min · database · leetcode · Last updated: Jul 14, 2025

Longest Common Subpath

November 29, 2024 · 10 min · array · binary-search · hash-function · leetcode · rolling-hash · suffix-array · Last updated: Aug 2, 2025

Longest Continuous Increasing Subsequence

November 29, 2024 · 4 min · array · leetcode · Last updated: Aug 2, 2025

Longest Even Odd Subarray With Threshold

November 29, 2024 · 6 min · array · leetcode · sliding-window · Last updated: Aug 2, 2025

Longest Harmonious Subsequence

November 29, 2024 · 4 min · array · counting · hash-table · leetcode · sliding-window · sorting · Last updated: Aug 2, 2025

Longest Ideal Subsequence

November 29, 2024 · 5 min · dynamic-programming · hash-table · leetcode · string · Last updated: Aug 2, 2025

Longest Increasing Subsequence II

November 29, 2024 · 11 min · array · binary-indexed-tree · divide-and-conquer · dynamic-programming · leetcode · monotonic-queue · queue · segment-tree · Last updated: Aug 2, 2025

Longest Mountain in Array

November 29, 2024 · 5 min · array · dynamic-programming · enumeration · leetcode · two-pointers · Last updated: Aug 2, 2025

Longest Nice Substring

November 29, 2024 · 4 min · bit-manipulation · divide-and-conquer · hash-table · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Longest Non-decreasing Subarray From Two Arrays

November 29, 2024 · 6 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Longest Uncommon Subsequence II

November 29, 2024 · 6 min · array · hash-table · leetcode · sorting · string · two-pointers · Last updated: Aug 2, 2025

Longest Uploaded Prefix

November 29, 2024 · 4 min · binary-indexed-tree · binary-search · design · heap-priority-queue · leetcode · ordered-set · segment-tree · union-find · Last updated: Aug 2, 2025

Longest Well-Performing Interval

November 29, 2024 · 5 min · array · hash-table · leetcode · monotonic-stack · prefix-sum · stack · Last updated: Aug 2, 2025

Loud and Rich

November 29, 2024 · 6 min · array · depth-first-search · graph · leetcode · topological-sort · Last updated: Aug 2, 2025

Make a Square with the Same Color

November 29, 2024 · 6 min · array · enumeration · leetcode · matrix · Last updated: Aug 2, 2025

Make String a Subsequence Using Cyclic Increments

November 29, 2024 · 5 min · leetcode · string · two-pointers · video · Last updated: Aug 2, 2025

Make Three Strings Equal

November 29, 2024 · 4 min · leetcode · string · Last updated: Aug 2, 2025

Map Sum Pairs

November 29, 2024 · 4 min · design · hash-table · leetcode · string · trie · Last updated: Aug 2, 2025

Mark Elements on Array by Performing Queries

November 29, 2024 · 8 min · array · hash-table · heap-priority-queue · leetcode · simulation · sorting · Last updated: Aug 2, 2025

Match Substring After Replacement

November 29, 2024 · 6 min · array · hash-table · leetcode · string · string-matching · Last updated: Aug 2, 2025

Matrix Diagonal Sum

November 29, 2024 · 3 min · array · leetcode · matrix · Last updated: Aug 2, 2025

Max Increase to Keep City Skyline

November 29, 2024 · 5 min · array · greedy · leetcode · matrix · Last updated: Aug 2, 2025

Max Pair Sum in an Array

November 29, 2024 · 6 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

Max Sum of a Pair With Equal Sum of Digits

November 29, 2024 · 10 min · array · hash-table · heap-priority-queue · leetcode · sorting · video · Last updated: Aug 2, 2025

Max Value of Equation

November 29, 2024 · 6 min · array · heap-priority-queue · leetcode · monotonic-queue · queue · sliding-window · Last updated: Aug 2, 2025

Maximize Consecutive Elements in an Array After Modification

November 29, 2024 · 6 min · array · dynamic-programming · leetcode · sorting · Last updated: Aug 2, 2025

Maximize Number of Subsequences in a String

November 29, 2024 · 6 min · greedy · leetcode · prefix-sum · string · Last updated: Aug 2, 2025

Maximize Palindrome Length From Subsequences

November 29, 2024 · 7 min · dynamic-programming · leetcode · string · Last updated: Aug 2, 2025

Maximize Score of Numbers in Ranges

November 29, 2024 · 6 min · array · binary-search · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Maximize the Minimum Powered City

November 29, 2024 · 9 min · array · binary-search · greedy · leetcode · prefix-sum · queue · sliding-window · Last updated: Aug 2, 2025

Maximize the Total Height of Unique Towers

November 29, 2024 · 4 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Maximize Win From Two Segments

November 29, 2024 · 6 min · array · binary-search · leetcode · sliding-window · Last updated: Aug 2, 2025

Maximum AND Sum of Array

November 29, 2024 · 8 min · array · bit-manipulation · bitmask · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Maximum Area of Longest Diagonal Rectangle

November 29, 2024 · 4 min · array · binary-indexed-tree · binary-search · bit-manipulation · bitmask · counting · depth-first-search · dynamic-programming · enumeration · geometry · greedy · hash-function · hash-table · leetcode · math · rolling-hash · sorting · string · string-matching · tree · two-pointers · Last updated: Aug 2, 2025

Maximum Balanced Subsequence Sum

November 29, 2024 · 9 min · array · binary-indexed-tree · binary-search · dynamic-programming · leetcode · segment-tree · Last updated: Aug 2, 2025

Maximum Consecutive Floors Without Special Floors

November 29, 2024 · 4 min · array · leetcode · sorting · Last updated: Aug 2, 2025

Maximum Deletions on a String

November 29, 2024 · 6 min · dynamic-programming · hash-function · leetcode · rolling-hash · string · string-matching · Last updated: Aug 2, 2025

Maximum Difference Score in a Grid

November 29, 2024 · 7 min · array · dynamic-programming · leetcode · matrix · Last updated: Aug 2, 2025

Maximum Element-Sum of a Complete Subset of Indices

November 29, 2024 · 6 min · array · leetcode · math · number-theory · Last updated: Aug 2, 2025

Maximum Energy Boost From Two Drinks

November 29, 2024 · 5 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Maximum Frequency of an Element After Performing Operations II

November 29, 2024 · 7 min · array · binary-search · leetcode · prefix-sum · sliding-window · sorting · Last updated: Aug 2, 2025

Maximum Good Subarray Sum

November 29, 2024 · 6 min · array · hash-table · leetcode · prefix-sum · Last updated: Aug 2, 2025

Maximum Height of a Triangle

November 29, 2024 · 4 min · array · enumeration · leetcode · Last updated: Aug 2, 2025

Maximum Ice Cream Bars

November 29, 2024 · 5 min · array · counting-sort · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Maximum Length of Subarray With Positive Product

November 29, 2024 · 6 min · array · dynamic-programming · greedy · leetcode · Last updated: Aug 2, 2025

Maximum Nesting Depth of Two Valid Parentheses Strings

November 29, 2024 · 4 min · leetcode · stack · string · Last updated: Aug 2, 2025

Maximum Number of Balls in a Box

November 29, 2024 · 5 min · counting · hash-table · leetcode · math · Last updated: Aug 2, 2025

Maximum Number of Consecutive Values You Can Make

November 29, 2024 · 4 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Maximum Number of Eaten Apples

November 29, 2024 · 7 min · array · greedy · heap-priority-queue · leetcode · Last updated: Aug 2, 2025

Maximum Number of Groups Getting Fresh Donuts

November 29, 2024 · 8 min · array · bit-manipulation · bitmask · dynamic-programming · leetcode · memoization · Last updated: Aug 2, 2025

Maximum Number of Moves to Kill All Pawns

November 29, 2024 · 17 min · array · bit-manipulation · bitmask · breadth-first-search · game-theory · leetcode · math · Last updated: Aug 2, 2025

Maximum Number of Non-overlapping Palindrome Substrings

November 29, 2024 · 7 min · dynamic-programming · greedy · leetcode · string · two-pointers · Last updated: Aug 2, 2025

Maximum Number of Non-Overlapping Subarrays With Sum Equals Target

November 29, 2024 · 4 min · array · greedy · hash-table · leetcode · prefix-sum · Last updated: Aug 2, 2025

Maximum Number of Non-Overlapping Substrings

November 29, 2024 · 9 min · greedy · leetcode · string · Last updated: Aug 2, 2025

Maximum Number of Operations With the Same Score I

November 29, 2024 · 6 min · array · leetcode · simulation · Last updated: Aug 2, 2025

Maximum Number of Pairs in Array

November 29, 2024 · 4 min · array · counting · hash-table · leetcode · Last updated: Aug 2, 2025

Maximum Number of Robots Within Budget

November 29, 2024 · 6 min · array · binary-search · heap-priority-queue · leetcode · monotonic-queue · prefix-sum · queue · sliding-window · Last updated: Aug 2, 2025

Maximum Number of Words Found in Sentences

November 29, 2024 · 4 min · array · leetcode · string · Last updated: Aug 2, 2025

Maximum Number of Words You Can Type

November 29, 2024 · 4 min · hash-table · leetcode · string · Last updated: Aug 2, 2025

Maximum Odd Binary Number

November 29, 2024 · 3 min · greedy · leetcode · math · string · Last updated: Aug 2, 2025

Maximum OR

November 29, 2024 · 5 min · array · bit-manipulation · greedy · leetcode · prefix-sum · Last updated: Aug 2, 2025

Maximum Path Quality of a Graph

November 29, 2024 · 8 min · array · backtracking · graph · leetcode · Last updated: Aug 2, 2025

Maximum Points After Collecting Coins From All Nodes

November 29, 2024 · 9 min · array · bit-manipulation · depth-first-search · dynamic-programming · leetcode · tree · Last updated: Aug 2, 2025

Maximum Points After Enemy Battles

November 29, 2024 · 6 min · array · greedy · leetcode · Last updated: Aug 2, 2025

Maximum Points Tourist Can Earn

November 29, 2024 · 6 min · array · dynamic-programming · leetcode · matrix · Last updated: Aug 2, 2025

Maximum Prime Difference

November 29, 2024 · 5 min · array · leetcode · math · number-theory · Last updated: Aug 2, 2025

Maximum Product After K Increments

November 29, 2024 · 5 min · array · greedy · heap-priority-queue · leetcode · Last updated: Aug 2, 2025

Maximum Product Difference Between Two Pairs

November 29, 2024 · 3 min · array · leetcode · sorting · Last updated: Aug 2, 2025

Maximum Product of the Length of Two Palindromic Substrings

November 29, 2024 · 7 min · hash-function · leetcode · rolling-hash · string · Last updated: Aug 2, 2025

Maximum Profit of Operating a Centennial Wheel

November 29, 2024 · 8 min · array · leetcode · simulation · Last updated: Aug 2, 2025

Maximum Score After Splitting a String

November 29, 2024 · 4 min · leetcode · prefix-sum · string · Last updated: Aug 2, 2025

Maximum Score From Grid Operations

November 29, 2024 · 7 min · array · dynamic-programming · leetcode · matrix · prefix-sum · Last updated: Aug 2, 2025

Maximum Score From Removing Stones

November 29, 2024 · 3 min · greedy · heap-priority-queue · leetcode · math · Last updated: Aug 2, 2025

Maximum Score Of Spliced Array

November 29, 2024 · 6 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Maximum Segment Sum After Removals

November 29, 2024 · 9 min · array · leetcode · ordered-set · prefix-sum · union-find · Last updated: Aug 2, 2025

Maximum Side Length of a Square with Sum Less than or Equal to Threshold

November 29, 2024 · 7 min · array · binary-search · leetcode · matrix · prefix-sum · Last updated: Aug 2, 2025

Maximum Size of a Set After Removals

November 29, 2024 · 5 min · array · greedy · hash-table · leetcode · Last updated: Aug 2, 2025

Maximum Spending After Buying Items

November 29, 2024 · 8 min · array · greedy · heap-priority-queue · leetcode · matrix · sorting · Last updated: Aug 2, 2025

Maximum Split of Positive Even Integers

November 29, 2024 · 5 min · backtracking · greedy · leetcode · math · Last updated: Aug 2, 2025

Maximum Strength of K Disjoint Subarrays

November 29, 2024 · 7 min · array · dynamic-programming · leetcode · prefix-sum · Last updated: Aug 2, 2025

Maximum Strictly Increasing Cells in a Matrix

November 29, 2024 · 8 min · array · binary-search · dynamic-programming · hash-table · leetcode · matrix · memoization · ordered-set · sorting · Last updated: Aug 2, 2025

Maximum Strong Pair XOR I

November 29, 2024 · 4 min · array · bit-manipulation · hash-table · leetcode · sliding-window · trie · Last updated: Aug 2, 2025

Maximum Sum of Almost Unique Subarray

November 29, 2024 · 6 min · array · hash-table · leetcode · sliding-window · Last updated: Aug 2, 2025

Maximum Sum of Subsequence With Non-adjacent Elements

November 29, 2024 · 7 min · array · divide-and-conquer · dynamic-programming · leetcode · segment-tree · Last updated: Aug 2, 2025

Maximum Sum of Two Non-Overlapping Subarrays

November 29, 2024 · 7 min · array · dynamic-programming · leetcode · sliding-window · Last updated: Aug 2, 2025

Maximum Total Reward Using Operations I

November 29, 2024 · 5 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Maximum Total Reward Using Operations II

November 29, 2024 · 5 min · array · bit-manipulation · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Maximum Twin Sum of a Linked List

November 29, 2024 · 6 min · leetcode · linked-list · stack · two-pointers · Last updated: Aug 2, 2025

Maximum Units on a Truck

November 29, 2024 · 4 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Maximum Value after Insertion

November 29, 2024 · 4 min · greedy · leetcode · string · Last updated: Aug 2, 2025

Maximum Value Sum by Placing Three Rooks II

November 29, 2024 · 6 min · array · dynamic-programming · enumeration · leetcode · matrix · Last updated: Aug 2, 2025

Maximum White Tiles Covered by a Carpet

November 29, 2024 · 7 min · array · binary-search · greedy · leetcode · prefix-sum · sorting · Last updated: Aug 2, 2025

Maximum Xor Product

November 29, 2024 · 5 min · bit-manipulation · greedy · leetcode · math · Last updated: Aug 2, 2025

Maximum XOR With an Element From Array

November 29, 2024 · 10 min · array · bit-manipulation · leetcode · trie · Last updated: Aug 2, 2025

Memoize

November 29, 2024 · 4 min · leetcode · Last updated: Aug 2, 2025

Merge In Between Linked Lists

November 29, 2024 · 5 min · leetcode · linked-list · Last updated: Aug 2, 2025

Method Chaining Problem

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Mice and Cheese

November 29, 2024 · 5 min · array · greedy · heap-priority-queue · leetcode · sorting · Last updated: Aug 2, 2025

Minesweeper

November 29, 2024 · 8 min · array · breadth-first-search · depth-first-search · leetcode · matrix · Last updated: Aug 2, 2025

Minimize Hamming Distance After Swap Operations

November 29, 2024 · 7 min · array · depth-first-search · leetcode · union-find · Last updated: Aug 2, 2025

Minimize Manhattan Distances

November 29, 2024 · 6 min · array · geometry · leetcode · math · ordered-set · sorting · Last updated: Aug 2, 2025

Minimize Maximum Pair Sum in Array

November 29, 2024 · 3 min · array · greedy · leetcode · sorting · two-pointers · Last updated: Aug 2, 2025

Minimize OR of Remaining Elements Using Operations

November 29, 2024 · 5 min · array · bit-manipulation · greedy · leetcode · Last updated: Aug 2, 2025

Minimize the Maximum of Two Arrays

November 29, 2024 · 8 min · binary-search · leetcode · math · number-theory · Last updated: Aug 2, 2025

Minimum Absolute Difference Queries

November 29, 2024 · 7 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

Minimum Absolute Sum Difference

November 29, 2024 · 7 min · array · binary-search · leetcode · ordered-set · sorting · Last updated: Aug 2, 2025

Minimum Addition to Make Integer Beautiful

November 29, 2024 · 5 min · greedy · leetcode · math · Last updated: Aug 2, 2025

Minimum Adjacent Swaps for K Consecutive Ones

November 29, 2024 · 6 min · array · greedy · leetcode · prefix-sum · sliding-window · Last updated: Aug 2, 2025

Minimum Adjacent Swaps to Reach the Kth Smallest Number

November 29, 2024 · 8 min · greedy · leetcode · string · two-pointers · Last updated: Aug 2, 2025

Minimum Amount of Damage Dealt to Bob

November 29, 2024 · 4 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Minimum Amount of Time to Fill Cups

November 29, 2024 · 3 min · array · greedy · heap-priority-queue · leetcode · sorting · Last updated: Aug 2, 2025

Minimum Area Rectangle

November 29, 2024 · 5 min · array · geometry · hash-table · leetcode · math · sorting · Last updated: Aug 2, 2025

Minimum Array Sum

November 29, 2024 · 3 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Minimum Average Difference

November 29, 2024 · 6 min · array · leetcode · prefix-sum · Last updated: Aug 2, 2025

Minimum Average of Smallest and Largest Elements

November 29, 2024 · 4 min · array · leetcode · sorting · two-pointers · Last updated: Aug 2, 2025

Minimum Common Value

November 29, 2024 · 4 min · array · binary-search · hash-table · leetcode · two-pointers · Last updated: Aug 2, 2025

Minimum Cost for Cutting Cake II

November 29, 2024 · 7 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Minimum Cost Homecoming of a Robot in a Grid

November 29, 2024 · 6 min · array · greedy · leetcode · Last updated: Aug 2, 2025

Minimum Cost to Equalize Array

November 29, 2024 · 6 min · array · enumeration · greedy · leetcode · Last updated: Aug 2, 2025

Minimum Cost to Make All Characters Equal

November 29, 2024 · 6 min · dynamic-programming · greedy · leetcode · string · Last updated: Aug 2, 2025

Minimum Cost to Make Array Equalindromic

November 29, 2024 · 6 min · array · binary-search · greedy · leetcode · math · sorting · Last updated: Aug 2, 2025

Minimum Cost to Reach Destination in Time

November 29, 2024 · 8 min · array · dynamic-programming · graph · leetcode · Last updated: Aug 2, 2025

Minimum Cost to Set Cooking Time

November 29, 2024 · 8 min · enumeration · leetcode · math · Last updated: Aug 2, 2025

Minimum Cost to Split an Array

November 29, 2024 · 6 min · array · counting · dynamic-programming · hash-table · leetcode · Last updated: Aug 2, 2025

Minimum Deletions to Make Array Beautiful

November 29, 2024 · 4 min · array · greedy · leetcode · stack · Last updated: Aug 2, 2025

Minimum Deletions to Make Array Divisible

November 29, 2024 · 4 min · array · heap-priority-queue · leetcode · math · number-theory · sorting · Last updated: Aug 2, 2025

Minimum Difference in Sums After Removal of Elements

November 29, 2024 · 6 min · array · dynamic-programming · heap-priority-queue · leetcode · Last updated: Aug 2, 2025

Minimum Distance to the Target Element

November 29, 2024 · 4 min · array · leetcode · Last updated: Aug 2, 2025

Minimum Division Operations to Make Array Non Decreasing

November 29, 2024 · 6 min · array · greedy · leetcode · math · number-theory · Last updated: Aug 2, 2025

Minimum Edge Weight Equilibrium Queries in a Tree

November 29, 2024 · 15 min · array · graph · leetcode · strongly-connected-component · tree · Last updated: Aug 8, 2025

Minimum Impossible OR

November 29, 2024 · 3 min · array · bit-manipulation · brainteaser · leetcode · Last updated: Aug 2, 2025

Minimum Incompatibility

November 29, 2024 · 12 min · array · bit-manipulation · bitmask · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Minimum Initial Energy to Finish Tasks

November 29, 2024 · 5 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Minimum Jumps to Reach Home

November 29, 2024 · 7 min · array · breadth-first-search · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Minimum Length of String After Deleting Similar Ends

November 29, 2024 · 5 min · leetcode · string · two-pointers · Last updated: Aug 2, 2025

Minimum Moves to Convert String

November 29, 2024 · 4 min · greedy · leetcode · string · Last updated: Aug 2, 2025

Minimum Moves to Reach Target with Rotations

November 29, 2024 · 12 min · array · breadth-first-search · leetcode · matrix · Last updated: Aug 2, 2025

Minimum Non-Zero Product of the Array Elements

November 29, 2024 · 6 min · greedy · leetcode · math · recursion · Last updated: Aug 2, 2025

Minimum Number of Chairs in a Waiting Room

November 29, 2024 · 5 min · leetcode · simulation · string · Last updated: Aug 2, 2025

Minimum Number of Frogs Croaking

November 29, 2024 · 5 min · counting · leetcode · string · Last updated: Aug 2, 2025

Minimum Number of Moves to Make Palindrome

November 29, 2024 · 6 min · binary-indexed-tree · greedy · leetcode · string · two-pointers · Last updated: Aug 2, 2025

Minimum Number of Operations to Convert Time

November 29, 2024 · 4 min · greedy · leetcode · string · Last updated: Aug 2, 2025

Minimum Number of Operations to Make All Array Elements Equal to 1

November 29, 2024 · 6 min · array · leetcode · math · number-theory · Last updated: Aug 2, 2025

Minimum Number of Operations to Make Array Continuous

November 29, 2024 · 5 min · array · binary-search · hash-table · leetcode · sliding-window · Last updated: Aug 2, 2025

Minimum Number of Operations to Make Array Empty

November 29, 2024 · 4 min · array · counting · greedy · hash-table · leetcode · Last updated: Aug 2, 2025

Minimum Number of Operations to Make Arrays Similar

November 29, 2024 · 6 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Minimum Number of Operations to Make String Sorted

November 29, 2024 · 9 min · combinatorics · leetcode · math · string · Last updated: Aug 2, 2025

Minimum Number of Operations to Make X and Y Equal

November 29, 2024 · 7 min · breadth-first-search · dynamic-programming · leetcode · memoization · Last updated: Aug 2, 2025

Minimum Number of Operations to Satisfy Conditions

November 29, 2024 · 7 min · array · dynamic-programming · leetcode · matrix · Last updated: Aug 2, 2025

Minimum Number of People to Teach

November 29, 2024 · 6 min · array · greedy · hash-table · leetcode · Last updated: Aug 2, 2025

Minimum Number of Pushes to Type Word I

November 29, 2024 · 4 min · greedy · leetcode · math · string · Last updated: Aug 2, 2025

Minimum Number of Valid Strings to Form Target II

November 29, 2024 · 6 min · array · binary-search · dynamic-programming · hash-function · leetcode · rolling-hash · segment-tree · string · string-matching · Last updated: Aug 2, 2025

Minimum Number of Visited Cells in a Grid

November 29, 2024 · 9 min · array · breadth-first-search · dynamic-programming · heap-priority-queue · leetcode · matrix · monotonic-stack · stack · union-find · Last updated: Aug 2, 2025

Minimum Number of Work Sessions to Finish the Tasks

November 29, 2024 · 7 min · array · backtracking · bit-manipulation · bitmask · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Minimum Numbers of Function Calls to Make Target Array

November 29, 2024 · 4 min · array · bit-manipulation · greedy · leetcode · Last updated: Aug 2, 2025

Minimum Obstacle Removal to Reach Corner

November 29, 2024 · 4 min · array · breadth-first-search · graph · heap-priority-queue · leetcode · matrix · shortest-path · Last updated: Aug 2, 2025

Minimum Operations to Make a Special Number

November 29, 2024 · 6 min · enumeration · greedy · leetcode · math · string · Last updated: Aug 2, 2025

Minimum Operations to Make a Subsequence

November 29, 2024 · 5 min · array · binary-search · greedy · hash-table · leetcode · Last updated: Aug 2, 2025

Minimum Operations to Make All Array Elements Equal

November 29, 2024 · 6 min · array · binary-search · leetcode · prefix-sum · sorting · Last updated: Aug 2, 2025

Minimum Operations to Make Array Equal II

November 29, 2024 · 6 min · array · greedy · leetcode · math · Last updated: Aug 2, 2025

Minimum Operations to Make Array Equal to Target

November 29, 2024 · 4 min · array · dynamic-programming · greedy · leetcode · monotonic-stack · stack · Last updated: Aug 2, 2025

Minimum Operations to Make Binary Array Elements Equal to One II

November 29, 2024 · 3 min · array · dynamic-programming · greedy · leetcode · Last updated: Aug 2, 2025

Minimum Operations to Make Median of Array Equal to K

November 29, 2024 · 3 min · array · greedy · leetcode · sorting · Last updated: Jan 1, 2025

Minimum Operations to Make the Array Alternating

November 29, 2024 · 8 min · array · counting · greedy · hash-table · leetcode · Last updated: Aug 2, 2025

Minimum Operations to Maximize Last Elements in Arrays

November 29, 2024 · 8 min · array · enumeration · leetcode · Last updated: Aug 2, 2025

Minimum Path Cost in a Grid

November 29, 2024 · 6 min · array · dynamic-programming · leetcode · matrix · Last updated: Aug 2, 2025

Minimum Positive Sum Subarray

November 29, 2024 · 5 min · array · leetcode · prefix-sum · sliding-window · Last updated: Aug 2, 2025

Minimum Processing Time

November 29, 2024 · 5 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Minimum Recolors to Get K Consecutive Black Blocks

November 29, 2024 · 3 min · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Minimum Rectangles to Cover Points

November 29, 2024 · 5 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Minimum Score by Changing Two Elements

November 29, 2024 · 3 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Minimum Score of a Path Between Two Cities

November 29, 2024 · 5 min · breadth-first-search · depth-first-search · graph · leetcode · union-find · Last updated: Aug 2, 2025

Minimum Seconds to Equalize a Circular Array

November 29, 2024 · 5 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

Minimum Skips to Arrive at Meeting On Time

November 29, 2024 · 7 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Minimum Space Wasted From Packaging

November 29, 2024 · 7 min · array · binary-search · leetcode · prefix-sum · sorting · Last updated: Aug 2, 2025

Minimum Suffix Flips

November 29, 2024 · 4 min · greedy · leetcode · string · Last updated: Aug 2, 2025

Minimum Sum of Mountain Triplets II

November 29, 2024 · 6 min · array · leetcode · Last updated: Aug 2, 2025

Minimum Sum of Squared Difference

November 29, 2024 · 6 min · array · binary-search · greedy · heap-priority-queue · leetcode · sorting · Last updated: Aug 2, 2025

Minimum Sum of Values by Dividing Array

November 29, 2024 · 6 min · array · binary-search · bit-manipulation · dynamic-programming · leetcode · queue · segment-tree · Last updated: Aug 2, 2025

Minimum Time to Finish the Race

November 29, 2024 · 8 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Minimum Time to Make Array Sum At Most x

November 29, 2024 · 6 min · array · dynamic-programming · leetcode · sorting · Last updated: Jan 1, 2025

Minimum Time to Remove All Cars Containing Illegal Goods

November 29, 2024 · 8 min · dynamic-programming · leetcode · string · Last updated: Jan 1, 2025

Minimum Time to Visit Disappearing Nodes

November 29, 2024 · 7 min · array · graph · heap-priority-queue · leetcode · shortest-path · Last updated: Aug 2, 2025

Minimum Time Visiting All Points

November 29, 2024 · 4 min · array · geometry · leetcode · math · Last updated: Aug 2, 2025

Minimum Total Cost to Make Arrays Unequal

November 29, 2024 · 8 min · array · counting · greedy · hash-table · leetcode · Last updated: Aug 2, 2025

Minimum Value to Get Positive Step by Step Sum

November 29, 2024 · 4 min · array · leetcode · prefix-sum · Last updated: Aug 2, 2025

Minimum Weighted Subgraph With the Required Paths

November 29, 2024 · 10 min · graph · leetcode · shortest-path · Last updated: Aug 2, 2025

Minimum White Tiles After Covering With Carpets

November 29, 2024 · 6 min · dynamic-programming · leetcode · prefix-sum · string · Last updated: Aug 2, 2025

Minimum XOR Sum of Two Arrays

November 29, 2024 · 5 min · array · bit-manipulation · bitmask · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Modify Columns

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Modify the Matrix

November 29, 2024 · 5 min · array · leetcode · matrix · Last updated: Aug 2, 2025

Monotone Increasing Digits

November 29, 2024 · 2 min · greedy · leetcode · math · Last updated: Aug 2, 2025

Most Frequent Even Element

November 29, 2024 · 2 min · array · counting · hash-table · leetcode · Last updated: Aug 2, 2025

Most Frequent Number Following Key In an Array

November 29, 2024 · 3 min · array · counting · hash-table · leetcode · Last updated: Aug 2, 2025

Movie Rating

November 29, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Moving Stones Until Consecutive II

November 29, 2024 · 4 min · array · leetcode · math · sorting · two-pointers · Last updated: Aug 2, 2025

Next Greater Element IV

November 29, 2024 · 6 min · array · binary-search · heap-priority-queue · leetcode · monotonic-stack · sorting · stack · Last updated: Aug 2, 2025

Nth Magical Number

November 29, 2024 · 5 min · binary-search · leetcode · math · Last updated: Aug 2, 2025

Number of Beautiful Partitions

November 29, 2024 · 6 min · dynamic-programming · leetcode · string · Last updated: Aug 2, 2025

Number of Bit Changes to Make Two Integers Equal

November 29, 2024 · 3 min · bit-manipulation · leetcode · Last updated: Aug 2, 2025

Number of Black Blocks

November 29, 2024 · 6 min · array · enumeration · hash-table · leetcode · Last updated: Aug 2, 2025

Number of Burgers with No Waste of Ingredients

November 29, 2024 · 4 min · leetcode · math · Last updated: Aug 2, 2025

Number of Different Integers in a String

November 29, 2024 · 4 min · hash-table · leetcode · string · Last updated: Aug 2, 2025

Number of Distinct Averages

November 29, 2024 · 4 min · array · hash-table · leetcode · sorting · two-pointers · Last updated: Aug 2, 2025

Number of Distinct Roll Sequences

November 29, 2024 · 7 min · dynamic-programming · leetcode · memoization · Last updated: Aug 2, 2025

Number of Employees Who Met the Target

November 29, 2024 · 3 min · array · leetcode · Last updated: Aug 2, 2025

Number of Even and Odd Bits

November 29, 2024 · 3 min · bit-manipulation · leetcode · Last updated: Aug 2, 2025

Number of Good Pairs

November 29, 2024 · 3 min · array · counting · hash-table · leetcode · math · Last updated: Aug 2, 2025

Number of Good Ways to Split a String

November 29, 2024 · 5 min · bit-manipulation · dynamic-programming · hash-table · leetcode · string · Last updated: Aug 2, 2025

Number of Orders in the Backlog

November 29, 2024 · 12 min · array · heap-priority-queue · leetcode · simulation · Last updated: Aug 2, 2025

Number of Pairs Satisfying Inequality

November 29, 2024 · 7 min · array · binary-indexed-tree · binary-search · divide-and-conquer · leetcode · merge-sort · ordered-set · segment-tree · Last updated: Aug 2, 2025

Number of People Aware of a Secret

November 29, 2024 · 6 min · dynamic-programming · leetcode · queue · simulation · Last updated: Aug 2, 2025

Number of Squareful Arrays

November 29, 2024 · 6 min · array · backtracking · bit-manipulation · bitmask · dynamic-programming · hash-table · leetcode · math · Last updated: Aug 2, 2025

Number of Strings Which Can Be Rearranged to Contain Substring

November 29, 2024 · 7 min · combinatorics · dynamic-programming · leetcode · math · Last updated: Aug 2, 2025

Number of Students Doing Homework at a Given Time

November 29, 2024 · 4 min · array · leetcode · Last updated: Aug 2, 2025

Number of Subarrays That Match a Pattern I

November 29, 2024 · 6 min · array · hash-function · leetcode · rolling-hash · string-matching · Last updated: Aug 2, 2025

Number of Subarrays With AND Value of K

November 29, 2024 · 4 min · array · binary-search · bit-manipulation · leetcode · segment-tree · Last updated: Aug 2, 2025

Number of Subarrays with Bounded Maximum

November 29, 2024 · 4 min · array · leetcode · two-pointers · Last updated: Aug 2, 2025

Number of Subarrays With GCD Equal to K

November 29, 2024 · 5 min · array · leetcode · math · number-theory · Last updated: Aug 2, 2025

Number of Subarrays With LCM Equal to K

November 29, 2024 · 5 min · array · leetcode · math · number-theory · Last updated: Aug 2, 2025

Number of Times Binary String Is Prefix-Aligned

November 29, 2024 · 4 min · array · leetcode · Last updated: Aug 2, 2025

Number of Unique Good Subsequences

November 29, 2024 · 5 min · dynamic-programming · leetcode · string · Last updated: Aug 2, 2025

Number of Valid Clock Times

November 29, 2024 · 5 min · enumeration · leetcode · string · Last updated: Aug 2, 2025

Number of Valid Move Combinations On Chessboard

November 29, 2024 · 14 min · array · backtracking · leetcode · simulation · string · Last updated: Aug 2, 2025

Number of Valid Words for Each Puzzle

November 29, 2024 · 7 min · array · bit-manipulation · hash-table · leetcode · string · trie · Last updated: Aug 2, 2025

Number of Ways to Divide a Long Corridor

November 29, 2024 · 7 min · dynamic-programming · leetcode · math · string · Last updated: Aug 2, 2025

Number of Ways to Reach a Position After Exactly k Steps

November 29, 2024 · 5 min · combinatorics · dynamic-programming · leetcode · math · Last updated: Aug 2, 2025

Number of Ways to Separate Numbers

November 29, 2024 · 8 min · dynamic-programming · leetcode · string · suffix-array · Last updated: Aug 2, 2025

Odd String Difference

November 29, 2024 · 5 min · array · hash-table · leetcode · string · Last updated: Aug 2, 2025

Optimal Partition of String

November 29, 2024 · 3 min · greedy · hash-table · leetcode · string · Last updated: Aug 2, 2025

Pairs of Songs With Total Durations Divisible by 60

November 29, 2024 · 3 min · array · counting · hash-table · leetcode · Last updated: Aug 2, 2025

Palindrome Partitioning IV

November 29, 2024 · 5 min · dynamic-programming · leetcode · string · Last updated: Aug 2, 2025

Palindrome Rearrangement Queries

November 29, 2024 · 12 min · hash-table · leetcode · prefix-sum · string · Last updated: Aug 2, 2025

Pancake Sorting

November 29, 2024 · 4 min · array · greedy · leetcode · sorting · two-pointers · Last updated: Jul 27, 2025

Parallel Courses II

November 29, 2024 · 7 min · bit-manipulation · bitmask · dynamic-programming · graph · leetcode · Last updated: Aug 2, 2025

Partition Array According to Given Pivot

November 29, 2024 · 6 min · array · daily-coding-problem · leetcode · simulation · two-pointers · Last updated: Aug 2, 2025

Partition Array into Disjoint Intervals

November 29, 2024 · 5 min · array · leetcode · Last updated: Aug 2, 2025

Partition Array Into Three Parts With Equal Sum

November 29, 2024 · 5 min · array · greedy · leetcode · Last updated: Aug 11, 2025

Partition String Into Minimum Beautiful Substrings

November 29, 2024 · 6 min · backtracking · dynamic-programming · hash-table · leetcode · string · Last updated: Aug 2, 2025

Partition String Into Substrings With Values at Most K

November 29, 2024 · 5 min · dynamic-programming · greedy · leetcode · string · Last updated: Jul 26, 2025

Path Crossing

November 29, 2024 · 4 min · hash-table · leetcode · string · Last updated: Aug 2, 2025

Path In Zigzag Labelled Binary Tree

November 29, 2024 · 4 min · binary-tree · leetcode · math · tree · Last updated: Aug 2, 2025

Peaks in Array

November 29, 2024 · 12 min · array · binary-indexed-tree · leetcode · segment-tree · Last updated: Aug 2, 2025

People Whose List of Favorite Companies Is Not a Subset of Another List

November 29, 2024 · 5 min · array · hash-table · leetcode · string · Last updated: Aug 2, 2025

Percentage of Letter in String

November 29, 2024 · 2 min · leetcode · string · Last updated: Aug 2, 2025

Plates Between Candles

November 29, 2024 · 8 min · array · binary-search · leetcode · prefix-sum · string · Last updated: Aug 2, 2025

Positions of Large Groups

November 29, 2024 · 4 min · leetcode · string · Last updated: Aug 2, 2025

Power of Heroes

November 29, 2024 · 5 min · array · dynamic-programming · leetcode · math · prefix-sum · sorting · Last updated: Aug 2, 2025

Primary Department for Each Employee

November 29, 2024 · 3 min · database · leetcode · Last updated: Jul 16, 2025

Prime Pairs With Target Sum

November 29, 2024 · 5 min · array · enumeration · leetcode · math · number-theory · Last updated: Aug 18, 2025

Print Words Vertically

November 29, 2024 · 4 min · array · leetcode · simulation · string · Last updated: Aug 2, 2025

Probability of a Two Boxes Having The Same Number of Distinct Balls

November 29, 2024 · 8 min · array · backtracking · combinatorics · dynamic-programming · leetcode · math · probability-and-statistics · Last updated: Aug 2, 2025

Process Restricted Friend Requests

November 29, 2024 · 8 min · graph · leetcode · union-find · Last updated: Aug 2, 2025

Product Price at a Given Date

November 29, 2024 · 3 min · database · leetcode · Last updated: Jul 16, 2025

Product Sales Analysis III

November 29, 2024 · 3 min · database · leetcode · Last updated: Jul 16, 2025

Project Employees I

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Projection Area of 3D Shapes

November 29, 2024 · 4 min · array · geometry · leetcode · math · matrix · Last updated: Aug 2, 2025

Pyramid Transition Matrix

November 29, 2024 · 7 min · bit-manipulation · breadth-first-search · depth-first-search · leetcode · Last updated: Aug 2, 2025

Queens That Can Attack the King

November 29, 2024 · 5 min · array · leetcode · matrix · simulation · Last updated: Aug 2, 2025

Queries on a Permutation With Key

November 29, 2024 · 4 min · array · binary-indexed-tree · leetcode · simulation · Last updated: Aug 2, 2025

Queries on Number of Points Inside a Circle

November 29, 2024 · 4 min · array · geometry · leetcode · math · Last updated: Aug 2, 2025

Queries Quality and Percentage

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Range Product Queries of Powers

November 29, 2024 · 7 min · array · bit-manipulation · leetcode · prefix-sum · Last updated: Aug 2, 2025

Reach a Number

November 29, 2024 · 4 min · binary-search · leetcode · math · Last updated: Aug 2, 2025

Reachable Nodes With Restrictions

November 29, 2024 · 6 min · array · breadth-first-search · depth-first-search · graph · hash-table · leetcode · tree · union-find · Last updated: Aug 2, 2025

Rearrange Array to Maximize Prefix Score

November 29, 2024 · 4 min · array · greedy · leetcode · prefix-sum · sorting · Last updated: Aug 2, 2025

Rearrange Characters to Make Target String

November 29, 2024 · 5 min · counting · hash-table · leetcode · string · Last updated: Aug 2, 2025

Rearrange K Substrings to Form Target String

November 29, 2024 · 5 min · hash-table · leetcode · sorting · string · Last updated: Aug 2, 2025

Rearrange Spaces Between Words

November 29, 2024 · 5 min · leetcode · string · Last updated: Aug 2, 2025

Rearrange Words in a Sentence

November 29, 2024 · 4 min · leetcode · sorting · string · Last updated: Aug 2, 2025

Rearranging Fruits

November 29, 2024 · 7 min · array · greedy · hash-table · leetcode · Last updated: Aug 2, 2025

Redistribute Characters to Make All Strings Equal

November 29, 2024 · 3 min · counting · hash-table · leetcode · string · Last updated: Aug 2, 2025

Reduction Operations to Make the Array Elements Equal

November 29, 2024 · 4 min · array · leetcode · sorting · Last updated: Aug 2, 2025

Reformat Date

November 29, 2024 · 3 min · leetcode · string · Last updated: Aug 2, 2025

Reformat Phone Number

November 29, 2024 · 6 min · leetcode · string · Last updated: Aug 2, 2025

Reformat The String

November 29, 2024 · 6 min · leetcode · string · Last updated: Aug 2, 2025

Relocate Marbles

November 29, 2024 · 5 min · array · hash-table · leetcode · simulation · sorting · Last updated: Aug 2, 2025

Remove Methods From Project

November 29, 2024 · 10 min · breadth-first-search · depth-first-search · graph · leetcode · Last updated: Aug 8, 2025

Remove Zero Sum Consecutive Nodes from Linked List

November 29, 2024 · 5 min · hash-table · leetcode · linked-list · Last updated: Aug 10, 2025

Removing Minimum Number of Magic Beans

November 29, 2024 · 5 min · array · enumeration · greedy · leetcode · prefix-sum · sorting · Last updated: Aug 2, 2025

Rename Columns

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Replace All ?’s to Avoid Consecutive Repeating Characters

November 29, 2024 · 4 min · leetcode · string · Last updated: Aug 2, 2025

Replace All Digits with Characters

November 29, 2024 · 3 min · leetcode · string · Last updated: Aug 2, 2025

Replace Non-Coprime Numbers in Array

November 29, 2024 · 6 min · array · leetcode · math · number-theory · stack · Last updated: Aug 2, 2025

Reshape Data- Concatenate

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Reshape Data- Melt

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Reshape the Matrix

November 29, 2024 · 4 min · array · leetcode · matrix · simulation · Last updated: Aug 2, 2025

Reveal Cards In Increasing Order

November 29, 2024 · 4 min · array · leetcode · queue · simulation · sorting · Last updated: Aug 2, 2025

Reverse Subarray To Maximize Array Value

November 29, 2024 · 6 min · array · greedy · leetcode · math · Last updated: Aug 2, 2025

Right Triangles

November 29, 2024 · 6 min · array · combinatorics · counting · hash-table · leetcode · math · Last updated: Aug 2, 2025

Rings and Rods

November 29, 2024 · 5 min · hash-table · leetcode · string · Last updated: Aug 2, 2025

Robot Collisions

November 29, 2024 · 10 min · array · leetcode · simulation · sorting · stack · Last updated: Aug 2, 2025

Robot Return to Origin

November 29, 2024 · 4 min · leetcode · simulation · string · Last updated: Aug 2, 2025

Running Sum of 1d Array

November 29, 2024 · 3 min · array · leetcode · prefix-sum · Last updated: Aug 2, 2025

Select Cells in Grid With Maximum Score

November 29, 2024 · 7 min · array · bit-manipulation · bitmask · dynamic-programming · leetcode · matrix · Last updated: Aug 2, 2025

Self Dividing Numbers

November 29, 2024 · 4 min · leetcode · math · Last updated: Aug 2, 2025

Semi-Ordered Permutation

November 29, 2024 · 5 min · array · leetcode · simulation · Last updated: Aug 2, 2025

Sequential Digits

November 29, 2024 · 4 min · enumeration · leetcode · Last updated: Aug 2, 2025

Shift Distance Between Two Strings

November 29, 2024 · 8 min · array · leetcode · prefix-sum · string · Last updated: Aug 2, 2025

Shifting Letters

November 29, 2024 · 4 min · array · leetcode · prefix-sum · string · Last updated: Jun 28, 2025

Shortest Distance After Road Addition Queries II

November 29, 2024 · 5 min · array · graph · greedy · leetcode · ordered-set · Last updated: Aug 2, 2025

Shortest Impossible Sequence of Rolls

November 29, 2024 · 3 min · array · greedy · hash-table · leetcode · Last updated: Aug 2, 2025

Shortest String That Contains Three Strings

November 29, 2024 · 3 min · enumeration · greedy · leetcode · string · Last updated: Aug 2, 2025

Shortest Subarray With OR at Least K I

November 29, 2024 · 3 min · array · bit-manipulation · leetcode · sliding-window · Last updated: Aug 2, 2025

Shortest Uncommon Substring in an Array

November 29, 2024 · 4 min · array · hash-table · leetcode · string · trie · Last updated: Aug 2, 2025

Shuffle String

November 29, 2024 · 2 min · array · leetcode · string · Last updated: Aug 2, 2025

Simple Bank System

November 29, 2024 · 4 min · array · design · hash-table · leetcode · simulation · Last updated: Aug 2, 2025

Simplified Fractions

November 29, 2024 · 2 min · leetcode · math · number-theory · string · Last updated: Aug 2, 2025

Sleep

November 29, 2024 · 1 min · leetcode · Last updated: Aug 2, 2025

Sliding Subarray Beauty

November 29, 2024 · 4 min · array · hash-table · leetcode · sliding-window · Last updated: Aug 2, 2025

Slowest Key

November 29, 2024 · 4 min · array · leetcode · string · Last updated: Aug 2, 2025

Smallest Even Multiple

November 29, 2024 · 2 min · leetcode · math · number-theory · Last updated: Aug 2, 2025

Smallest Integer Divisible by K

November 29, 2024 · 2 min · hash-table · leetcode · math · Last updated: Aug 2, 2025

Smallest Missing Non-negative Integer After Operations

November 29, 2024 · 3 min · array · greedy · hash-table · leetcode · math · Last updated: Aug 2, 2025

Smallest Range II

November 29, 2024 · 4 min · array · greedy · leetcode · math · sorting · Last updated: Aug 2, 2025

Smallest String Starting From Leaf

November 29, 2024 · 4 min · backtracking · binary-tree · depth-first-search · leetcode · string · tree · Last updated: Aug 2, 2025

Smallest String With A Given Numeric Value

November 29, 2024 · 4 min · greedy · leetcode · string · Last updated: Aug 2, 2025

Smallest Value After Replacing With Sum of Prime Factors

November 29, 2024 · 4 min · leetcode · math · number-theory · simulation · Last updated: Aug 2, 2025

Smallest Value of the Rearranged Number

November 29, 2024 · 5 min · leetcode · math · sorting · Last updated: Aug 2, 2025

Snail Traversal

November 29, 2024 · 4 min · leetcode · Last updated: Aug 2, 2025

Solve the Equation

November 29, 2024 · 9 min · leetcode · math · simulation · string · Last updated: Aug 2, 2025

Sort Array By Parity II

November 29, 2024 · 7 min · array · leetcode · sorting · two-pointers · Last updated: Aug 2, 2025

Sort By

November 29, 2024 · 6 min · leetcode · Last updated: Aug 2, 2025

Sort Items by Groups Respecting Dependencies

November 29, 2024 · 13 min · breadth-first-search · depth-first-search · graph · leetcode · topological-sort · Last updated: Aug 2, 2025

Sort Matrix by Diagonals

November 29, 2024 · 8 min · array · leetcode · matrix · sorting · Last updated: Aug 2, 2025

Sort the Students by Their Kth Score

November 29, 2024 · 3 min · array · leetcode · matrix · sorting · Last updated: Aug 2, 2025

Sorting the Sentence

November 29, 2024 · 4 min · leetcode · sorting · string · Last updated: Aug 2, 2025

Special Array 1

November 29, 2024 · 3 min · array · bits · leetcode · video · xor · Last updated: Aug 2, 2025

Special Binary String

November 29, 2024 · 6 min · leetcode · recursion · string · Last updated: Aug 2, 2025

Special Permutations

November 29, 2024 · 6 min · array · bit-manipulation · bitmask · dynamic-programming · leetcode · Last updated: Jul 26, 2025

Split a String in Balanced Strings

November 29, 2024 · 3 min · counting · greedy · leetcode · string · Last updated: Jul 26, 2025

Split Array into Fibonacci Sequence

November 29, 2024 · 6 min · backtracking · leetcode · string · Last updated: Jul 26, 2025

Split Array Into Maximum Number of Subarrays

November 29, 2024 · 4 min · array · bit-manipulation · greedy · leetcode · Last updated: Jul 26, 2025

Split the Array to Make Coprime Products

November 29, 2024 · 7 min · array · hash-table · leetcode · math · number-theory · Last updated: Jul 26, 2025

Split With Minimum Sum

November 29, 2024 · 4 min · greedy · leetcode · math · sorting · Last updated: Jul 26, 2025

Stamping The Sequence

November 29, 2024 · 7 min · greedy · leetcode · queue · stack · string · Last updated: Jul 26, 2025

Steps to Make Array Non-decreasing

November 29, 2024 · 3 min · array · leetcode · linked-list · monotonic-stack · stack · Last updated: Jul 27, 2025

Stone Game IX

November 29, 2024 · 5 min · array · counting · game-theory · greedy · leetcode · math · Last updated: Aug 2, 2025

Stream of Characters

November 29, 2024 · 8 min · array · data-stream · design · leetcode · string · trie · Last updated: Aug 2, 2025

Strictly Palindromic Number

November 29, 2024 · 2 min · brainteaser · leetcode · math · two-pointers · Last updated: Aug 2, 2025

Strong Password Checker II

November 29, 2024 · 5 min · leetcode · string · Last updated: Aug 2, 2025

Subarray With Elements Greater Than Varying Threshold

November 29, 2024 · 6 min · array · leetcode · monotonic-stack · stack · union-find · Last updated: Aug 2, 2025

Subarrays Distinct Element Sum of Squares I

November 29, 2024 · 4 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

Subarrays with K Different Integers

November 29, 2024 · 5 min · array · counting · hash-table · leetcode · sliding-window · Last updated: Aug 2, 2025

Subdomain Visit Count

November 29, 2024 · 5 min · array · counting · hash-table · leetcode · string · Last updated: Aug 2, 2025

Subrectangle Queries

November 29, 2024 · 5 min · array · design · leetcode · matrix · Last updated: Aug 2, 2025

Substring XOR Queries

November 29, 2024 · 7 min · array · bit-manipulation · hash-table · leetcode · string · Last updated: Aug 2, 2025

Substrings of Size Three with Distinct Characters

November 29, 2024 · 3 min · counting · hash-table · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Sum Multiples

November 29, 2024 · 4 min · leetcode · math · Last updated: Aug 2, 2025

Sum of Digits in Base K

November 29, 2024 · 3 min · leetcode · math · Last updated: Aug 2, 2025

Sum of Distances

November 29, 2024 · 6 min · array · hash-table · leetcode · prefix-sum · Last updated: Aug 2, 2025

Sum of Floored Pairs

November 29, 2024 · 7 min · array · binary-search · leetcode · math · prefix-sum · Last updated: Aug 2, 2025

Sum of Imbalance Numbers of All Subarrays

November 29, 2024 · 5 min · array · hash-table · leetcode · ordered-set · Last updated: Aug 2, 2025

Sum of Matrix After Queries

November 29, 2024 · 5 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

Sum of Nodes with Even-Valued Grandparent

November 29, 2024 · 4 min · binary-tree · breadth-first-search · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Sum of Numbers With Units Digit K

November 29, 2024 · 4 min · dynamic-programming · enumeration · greedy · leetcode · math · Last updated: Aug 2, 2025

Sum of Root To Leaf Binary Numbers

November 29, 2024 · 4 min · binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Sum of Scores of Built Strings

November 29, 2024 · 5 min · binary-search · hash-function · leetcode · rolling-hash · string · string-matching · suffix-array · Last updated: Aug 2, 2025

Sum of Squares of Special Elements

November 29, 2024 · 3 min · array · enumeration · leetcode · Last updated: Aug 2, 2025

Sum of Subsequence Widths

November 29, 2024 · 4 min · array · leetcode · math · sorting · Last updated: Aug 2, 2025

Sum of Unique Elements

November 29, 2024 · 2 min · array · counting · hash-table · leetcode · Last updated: Aug 2, 2025

Super Palindromes

November 29, 2024 · 6 min · enumeration · leetcode · math · Last updated: Aug 2, 2025

Super Washing Machines

November 29, 2024 · 4 min · array · greedy · leetcode · Last updated: Aug 2, 2025

Surface Area of 3D Shapes

November 29, 2024 · 4 min · array · geometry · leetcode · math · matrix · Last updated: Aug 2, 2025

Task Scheduler II

November 29, 2024 · 4 min · array · hash-table · leetcode · simulation · Last updated: Aug 2, 2025

The Earliest and Latest Rounds Where Players Compete

November 29, 2024 · 18 min · dynamic-programming · leetcode · memoization · Last updated: Jul 12, 2025

The kth Factor of n

November 29, 2024 · 3 min · leetcode · math · number-theory · Last updated: Aug 2, 2025

The Latest Login in 2020

November 29, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

The Two Sneaky Numbers of Digitville

November 29, 2024 · 3 min · array · hash-table · leetcode · math · Last updated: Aug 2, 2025

Thousand Separator

November 29, 2024 · 2 min · leetcode · string · Last updated: Aug 2, 2025

Throne Inheritance

November 29, 2024 · 6 min · depth-first-search · design · hash-table · leetcode · tree · Last updated: Aug 2, 2025

Tiling a Rectangle with the Fewest Squares

November 29, 2024 · 7 min · backtracking · leetcode · Last updated: Aug 2, 2025

Time Needed to Rearrange a Binary String

November 29, 2024 · 2 min · dynamic-programming · leetcode · simulation · string · Last updated: Aug 2, 2025

Time Taken to Mark All Nodes

November 29, 2024 · 4 min · depth-first-search · dynamic-programming · graph · leetcode · tree · Last updated: Aug 2, 2025

Timeout Cancellation

November 29, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Total Appeal of A String

November 29, 2024 · 4 min · dynamic-programming · hash-table · leetcode · string · Last updated: Aug 2, 2025

Transform to Chessboard

November 29, 2024 · 6 min · array · bit-manipulation · leetcode · math · matrix · Last updated: Aug 2, 2025

Tree of Coprimes

November 29, 2024 · 4 min · array · depth-first-search · leetcode · math · number-theory · tree · Last updated: Aug 2, 2025

Two Furthest Houses With Different Colors

November 29, 2024 · 3 min · array · greedy · leetcode · Last updated: Aug 2, 2025

Ugly Number III

November 29, 2024 · 3 min · binary-search · combinatorics · leetcode · math · number-theory · Last updated: Aug 2, 2025

Unique Morse Code Words

November 29, 2024 · 2 min · array · hash-table · leetcode · string · Last updated: Aug 2, 2025

Valid Arrangement of Pairs

November 29, 2024 · 4 min · depth-first-search · eulerian-circuit · graph · leetcode · Last updated: Aug 2, 2025

Valid Mountain Array

November 29, 2024 · 4 min · array · leetcode · Last updated: Jul 31, 2025

Valid Triangle Number

November 29, 2024 · 4 min · array · binary-search · greedy · leetcode · sorting · two-pointers · Last updated: Aug 2, 2025

Valid Word

November 29, 2024 · 4 min · leetcode · string · Last updated: Jul 15, 2025

Verbal Arithmetic Puzzle

November 29, 2024 · 10 min · array · backtracking · leetcode · math · string · Last updated: Aug 2, 2025

Visit Array Positions to Maximize Score

November 29, 2024 · 5 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Walking Robot Simulation II

November 29, 2024 · 8 min · design · leetcode · simulation · Last updated: Aug 2, 2025

Watering Plants II

November 29, 2024 · 7 min · array · leetcode · simulation · two-pointers · Last updated: Aug 2, 2025

Ways to Make a Fair Array

November 29, 2024 · 6 min · array · leetcode · prefix-sum · Last updated: Aug 2, 2025

Ways to Split Array Into Good Subarrays

November 29, 2024 · 4 min · array · dynamic-programming · leetcode · math · Last updated: Aug 2, 2025

Ways to Split Array Into Three Subarrays

November 29, 2024 · 6 min · array · binary-search · leetcode · prefix-sum · two-pointers · Last updated: Aug 2, 2025

Words Within Two Edits of Dictionary

November 29, 2024 · 5 min · array · leetcode · string · Last updated: Aug 2, 2025

XOR Operation in an Array

November 29, 2024 · 3 min · bit-manipulation · leetcode · math · Last updated: Aug 2, 2025

Zuma Game

November 29, 2024 · 12 min · breadth-first-search · dynamic-programming · leetcode · memoization · stack · string · Last updated: Aug 2, 2025

Minimum Equal Sum of Two Arrays After Replacing Zeros

November 29, 2024 · 4 min · array · greedy · leetcode · Last updated: Aug 2, 2025

Sequentially Ordinal Rank Tracker

November 28, 2024 · 8 min · data-stream · design · heap-priority-queue · leetcode · ordered-set · Last updated: Aug 2, 2025

Count Subarrays With Median K

November 28, 2024 · 3 min · array · hash-table · leetcode · prefix-sum · Last updated: Aug 2, 2025

Alt and Tab Simulation

November 27, 2024 · 5 min · array · hash-table · leetcode · simulation · Last updated: Aug 2, 2025

Better Compression of String

November 27, 2024 · 5 min · counting · hash-table · leetcode · sorting · string · Last updated: Aug 2, 2025

Bitwise OR of Adjacent Elements

November 27, 2024 · 2 min · array · bit-manipulation · leetcode · Last updated: Aug 2, 2025

Books with NULL Ratings

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Calculate Parking Fees and Duration

November 27, 2024 · 4 min · database · leetcode · Last updated: Jun 30, 2025

Calculate Product Final Price

November 27, 2024 · 3 min · database · leetcode · Last updated: Jul 1, 2025

Calculate Trapping Rain Water

November 27, 2024 · 3 min · database · leetcode · Last updated: Jul 1, 2025

CEO Subordinate Hierarchy

November 27, 2024 · 4 min · database · leetcode · Last updated: Jul 1, 2025

Construct String with Minimum Cost (Easy)

November 27, 2024 · 5 min · leetcode · Last updated: Jul 7, 2025

Constructing Two Increasing Arrays

November 27, 2024 · 7 min · array · dynamic-programming · leetcode · Last updated: Jul 7, 2025

Count Numbers With Unique Digits II

November 27, 2024 · 5 min · dynamic-programming · hash-table · leetcode · math · Last updated: Jul 27, 2025

Count Substrings With K-Frequency Characters II

November 27, 2024 · 5 min · hash-table · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Employee Task Duration and Concurrent Tasks

November 27, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

Employees Project Allocation

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Equalize Strings by Adding or Removing Characters at Ends

November 27, 2024 · 5 min · binary-search · dynamic-programming · hash-function · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Find Candidates for Data Scientist Position

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Find Longest Self-Contained Substring

November 27, 2024 · 7 min · binary-search · hash-table · leetcode · prefix-sum · string · Last updated: Aug 2, 2025

Find Overlapping Shifts II

November 27, 2024 · 6 min · database · leetcode · Last updated: Aug 2, 2025

Find Pattern in Infinite Stream I

November 27, 2024 · 5 min · array · hash-function · leetcode · rolling-hash · sliding-window · string-matching · Last updated: Aug 2, 2025

Find Pattern in Infinite Stream II

November 27, 2024 · 6 min · array · hash-function · leetcode · rolling-hash · sliding-window · string-matching · Last updated: Aug 2, 2025

Find Sorted Submatrices With Maximum Element at Most K

November 27, 2024 · 7 min · array · leetcode · matrix · monotonic-stack · stack · Last updated: Aug 2, 2025

Find the Index of Permutation

November 27, 2024 · 7 min · array · binary-indexed-tree · binary-search · divide-and-conquer · leetcode · merge-sort · ordered-set · segment-tree · Last updated: Aug 2, 2025

Find the Number of K-Even Arrays

November 27, 2024 · 8 min · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Find Top Performing Driver

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Find Top Scoring Students

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Find Trending Hashtags

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Friday Purchase III

November 27, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

Guess the Number Using Bitwise Questions I

November 27, 2024 · 3 min · bit-manipulation · interactive · leetcode · Last updated: Aug 2, 2025

Guess the Number Using Bitwise Questions II

November 27, 2024 · 3 min · bit-manipulation · interactive · leetcode · Last updated: Aug 2, 2025

Match Alphanumerical Pattern in Matrix I

November 27, 2024 · 10 min · array · hash-table · leetcode · matrix · string · Last updated: Aug 2, 2025

Maximum Array Hopping Score I

November 27, 2024 · 4 min · array · dynamic-programming · greedy · leetcode · monotonic-stack · stack · Last updated: Aug 2, 2025

Maximum Array Hopping Score II

November 27, 2024 · 5 min · array · greedy · leetcode · monotonic-stack · stack · Last updated: Aug 2, 2025

Maximum Number of Intersections on the Chart

November 27, 2024 · 5 min · array · binary-indexed-tree · geometry · leetcode · math · Last updated: Aug 2, 2025

Maximum Number of Potholes That Can Be Fixed

November 27, 2024 · 6 min · greedy · leetcode · sorting · string · Last updated: Aug 2, 2025

Maximum Number That Makes Result of Bitwise AND Zero

November 27, 2024 · 3 min · greedy · leetcode · sorting · string · Last updated: Aug 2, 2025

Maximum Total Area Occupied by Pistons

November 27, 2024 · 4 min · array · counting · hash-table · leetcode · prefix-sum · simulation · string · Last updated: Aug 2, 2025

Minimize Connected Groups by Inserting Interval

November 27, 2024 · 6 min · array · binary-search · leetcode · sliding-window · sorting · Last updated: Aug 2, 2025

Minimum Moves to Get a Peaceful Board

November 27, 2024 · 4 min · array · counting-sort · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Minimum Number of Increasing Subsequence to Be Removed

November 27, 2024 · 4 min · array · binary-search · leetcode · Last updated: Aug 2, 2025

Number of Subsequences with Odd Sum

November 27, 2024 · 5 min · array · combinatorics · dynamic-programming · leetcode · math · Last updated: Aug 2, 2025

Pizza Toppings Cost Analysis

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Premier League Table Ranking

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Second Highest Salary II

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Server Utilization Time

November 27, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

Sum of Consecutive Subarrays

November 27, 2024 · 8 min · array · dynamic-programming · leetcode · two-pointers · Last updated: Aug 2, 2025

The Number of Ways to Make the Sum

November 27, 2024 · 4 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

User Activities within Time Bounds

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Array of Objects to Matrix

November 27, 2024 · 5 min · leetcode · Last updated: Aug 2, 2025

Array Upper Bound

November 27, 2024 · 3 min · leetcode · Last updated: Aug 2, 2025

Bikes Last Time Used

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Bind Function to Context

November 27, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Calculate Compressed Mean

November 27, 2024 · 2 min · database · leetcode · Last updated: Jul 1, 2025

Calculate Orders Within Each Interval

November 27, 2024 · 3 min · database · leetcode · Last updated: Jun 30, 2025

Color the Triangle Red

November 27, 2024 · 4 min · array · leetcode · math · Last updated: Jul 7, 2025

Concatenate the Name and the Profession

November 27, 2024 · 2 min · database · leetcode · Last updated: Jul 7, 2025

Consecutive Transactions with Increasing Amounts

November 27, 2024 · 5 min · database · leetcode · Last updated: Jul 7, 2025

Count Artist Occurrences On Spotify Ranking List

November 27, 2024 · 2 min · database · leetcode · Last updated: Aug 2, 2025

Count Houses in a Circular Street

November 27, 2024 · 4 min · array · interactive · leetcode · Last updated: Aug 2, 2025

Count Nodes That Are Great Enough

November 27, 2024 · 9 min · binary-tree · depth-first-search · divide-and-conquer · leetcode · tree · Last updated: Jul 26, 2025

Count Occurrences in Text

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Count Substrings Without Repeating Character

November 27, 2024 · 5 min · hash-table · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Custom Interval

November 27, 2024 · 4 min · leetcode · Last updated: Aug 2, 2025

Customers with Maximum Number of Transactions on Consecutive Days

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Deep Merge of Two Objects

November 27, 2024 · 5 min · leetcode · Last updated: Aug 2, 2025

Deep Object Filter

November 27, 2024 · 4 min · leetcode · Last updated: Aug 2, 2025

Differences Between Two Objects

November 27, 2024 · 5 min · leetcode · Last updated: Aug 2, 2025

Election Results

November 27, 2024 · 4 min · leetcode · Last updated: Aug 2, 2025

Extract Kth Character From The Rope Tree

November 27, 2024 · 5 min · binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Find Active Users

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Find Latest Salaries

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Find Maximal Uncovered Ranges

November 27, 2024 · 6 min · array · leetcode · sorting · Last updated: Aug 2, 2025

Find Third Transaction

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Flight Occupancy and Waitlist Analysis

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Friday Purchases I

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Friday Purchases II

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Height of Special Binary Tree

November 27, 2024 · 5 min · binary-tree · breadth-first-search · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Highest Salaries Difference

November 27, 2024 · 3 min · database · leetcode · Last updated: Jul 26, 2025

Immediate Food Delivery III

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Infinite Method Object

November 27, 2024 · 2 min · leetcode · Last updated: Aug 2, 2025

Is Array a Preorder of Some ‌Binary Tree

November 27, 2024 · 5 min · binary-tree · depth-first-search · leetcode · stack · tree · Last updated: Aug 2, 2025

JSON Deep Equal

November 27, 2024 · 4 min · leetcode · Last updated: Aug 2, 2025

Loan Types

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Make Object Immutable

November 27, 2024 · 4 min · leetcode · Last updated: Aug 2, 2025

Make the Prefix Sum Non-negative

November 27, 2024 · 5 min · array · greedy · heap-priority-queue · leetcode · Last updated: Aug 2, 2025

Manager of the Largest Department

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Maximal Range That Each Element Is Maximum in It

November 27, 2024 · 6 min · array · leetcode · monotonic-stack · stack · Last updated: Aug 2, 2025

Maximum Frequency Score of a Subarray

November 27, 2024 · 6 min · array · hash-table · leetcode · math · sliding-window · stack · Last updated: Aug 2, 2025

Maximum Length of Semi-Decreasing Subarrays

November 27, 2024 · 4 min · array · leetcode · monotonic-stack · sorting · stack · Last updated: Aug 2, 2025

Maximum Number of Integers to Choose From a Range II

November 27, 2024 · 4 min · array · binary-search · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Maximum Profitable Triplets With Increasing Prices I

November 27, 2024 · 6 min · array · binary-indexed-tree · leetcode · segment-tree · Last updated: Aug 2, 2025

Maximum Profitable Triplets With Increasing Prices II

November 27, 2024 · 11 min · array · binary-indexed-tree · leetcode · segment-tree · Last updated: Aug 2, 2025

Minimum Number of Coins for Fruits II

November 27, 2024 · 5 min · array · dynamic-programming · heap-priority-queue · leetcode · monotonic-queue · queue · Last updated: Aug 2, 2025

Minimum Operations to Make Numbers Non-positive

November 27, 2024 · 6 min · array · binary-search · leetcode · Last updated: Aug 2, 2025

Minimum Time to Eat All Grains

November 27, 2024 · 7 min · array · binary-search · leetcode · sorting · two-pointers · Last updated: Jan 1, 2025

Most Expensive Item That Can Not Be Bought

November 27, 2024 · 2 min · dynamic-programming · leetcode · math · number-theory · Last updated: Aug 2, 2025

Number of Divisible Triplet Sums

November 27, 2024 · 4 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

Number of Equal Numbers Blocks

November 27, 2024 · 3 min · array · binary-search · interactive · leetcode · Last updated: Aug 2, 2025

Number of Good Binary Strings

November 27, 2024 · 5 min · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Number of Self-Divisible Permutations

November 27, 2024 · 5 min · array · backtracking · bit-manipulation · bitmask · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Partial Function with Placeholders

November 27, 2024 · 3 min · leetcode · Last updated: Aug 2, 2025

Popularity Percentage

November 27, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

Promise Pool

November 27, 2024 · 4 min · leetcode · Last updated: Aug 2, 2025

Query Batching

November 27, 2024 · 5 min · leetcode · Last updated: Aug 2, 2025

Smallest Number With Given Digit Product

November 27, 2024 · 3 min · greedy · leetcode · math · Last updated: Aug 2, 2025

The Knight’s Tour

November 27, 2024 · 5 min · array · backtracking · leetcode · matrix · Last updated: Aug 2, 2025

Time Taken to Cross the Door

November 27, 2024 · 5 min · array · leetcode · queue · simulation · Last updated: Aug 2, 2025

Top Three Wineries

November 27, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

Viewers Turned Streamers

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Account Balance

November 27, 2024 · 3 min · database · leetcode · Last updated: Jun 28, 2025

All the Matches of the League

November 27, 2024 · 2 min · database · leetcode · Last updated: Aug 2, 2025

Check for Contradictions in Equations

November 27, 2024 · 4 min · array · depth-first-search · graph · leetcode · union-find · Last updated: Jul 1, 2025

Check if an Array Is Consecutive

November 27, 2024 · 4 min · array · hash-table · leetcode · sorting · Last updated: Jul 3, 2025

Choose Edges to Maximize Score in a Tree

November 27, 2024 · 6 min · depth-first-search · dynamic-programming · leetcode · tree · Last updated: Jul 4, 2025

Closest Node to Path in Tree

November 27, 2024 · 12 min · array · breadth-first-search · depth-first-search · leetcode · tree · Last updated: Jul 6, 2025

Count Positions on Street With Required Brightness

November 27, 2024 · 7 min · array · leetcode · prefix-sum · Last updated: Aug 2, 2025

Count Strictly Increasing Subarrays

November 27, 2024 · 4 min · array · dynamic-programming · leetcode · math · Last updated: Aug 2, 2025

Customers With Strictly Increasing Purchases

November 27, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

Design SQL

November 27, 2024 · 6 min · array · design · hash-table · leetcode · string · Last updated: Aug 2, 2025

Design Video Sharing Platform

November 27, 2024 · 10 min · design · hash-table · leetcode · ordered-set · stack · Last updated: Aug 2, 2025

Drop Type 1 Orders for Customers With Type 0 Orders

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Dynamic Unpivoting of a Table

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Elements in Array After Removing and Replacing Elements

November 27, 2024 · 7 min · array · leetcode · Last updated: Aug 2, 2025

Finding the Topic of Each Post

November 27, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

Form a Chemical Bond

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Generate the Invoice

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Jump Game VIII

November 27, 2024 · 9 min · array · dynamic-programming · graph · leetcode · monotonic-stack · shortest-path · stack · Last updated: Aug 2, 2025

Maximize Total Tastiness of Purchased Fruits

November 27, 2024 · 10 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Maximum Alternating Subarray Sum

November 27, 2024 · 5 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Maximum Cost of Trip With K Highways

November 27, 2024 · 9 min · bit-manipulation · bitmask · dynamic-programming · graph · leetcode · Last updated: Aug 2, 2025

Maximum Number of Books You Can Take

November 27, 2024 · 7 min · array · dynamic-programming · leetcode · monotonic-stack · stack · Last updated: Aug 2, 2025

Maximum Profit From Trading Stocks

November 27, 2024 · 5 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Maximum Sum Score of Array

November 27, 2024 · 5 min · array · leetcode · prefix-sum · Last updated: Aug 2, 2025

Merge Operations to Turn Array Into a Palindrome

November 27, 2024 · 5 min · array · greedy · leetcode · two-pointers · Last updated: Aug 2, 2025

Merge Overlapping Events in the Same Hall

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Minimize Maximum Value in a Grid

November 27, 2024 · 11 min · array · graph · leetcode · matrix · sorting · topological-sort · union-find · Last updated: Aug 2, 2025

Minimum Adjacent Swaps to Make a Valid Array

November 27, 2024 · 5 min · array · greedy · leetcode · Last updated: Aug 2, 2025

Minimum Cost to Buy Apples

November 27, 2024 · 10 min · array · graph · heap-priority-queue · leetcode · shortest-path · Last updated: Aug 2, 2025

Minimum Cost to Reach City With Discounts

November 27, 2024 · 9 min · graph · heap-priority-queue · leetcode · shortest-path · Last updated: Aug 2, 2025

Minimum Cost to Separate Sentence Into Rows

November 27, 2024 · 7 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Minimum Costs Using the Train Line

November 27, 2024 · 6 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Minimum Flips in Binary Tree to Get Result

November 27, 2024 · 13 min · binary-tree · depth-first-search · dynamic-programming · leetcode · tree · Last updated: Aug 8, 2025

Minimum Number of Lines to Cover Points

November 27, 2024 · 8 min · array · backtracking · bit-manipulation · bitmask · dynamic-programming · geometry · hash-table · leetcode · math · Last updated: Aug 2, 2025

Minimum Split Into Subarrays With GCD Greater Than One

November 27, 2024 · 5 min · array · dynamic-programming · greedy · leetcode · math · number-theory · Last updated: Aug 2, 2025

Minimum Subarrays in a Valid Split

November 27, 2024 · 6 min · array · dynamic-programming · leetcode · math · number-theory · Last updated: Aug 2, 2025

Minimum Time to Kill All Monsters

November 27, 2024 · 9 min · array · bit-manipulation · bitmask · dynamic-programming · leetcode · Last updated: Jan 1, 2025

Number of Accounts That Did Not Stream

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Number of People That Can Be Seen in a Grid

November 27, 2024 · 8 min · array · leetcode · matrix · monotonic-stack · stack · Last updated: Aug 2, 2025

Number of Spaces Cleaning Robot Cleaned

November 27, 2024 · 6 min · array · leetcode · matrix · simulation · Last updated: Aug 2, 2025

Number of Subarrays Having Even Product

November 27, 2024 · 5 min · array · dynamic-programming · leetcode · math · Last updated: Aug 2, 2025

Number of Ways to Build House of Cards

November 27, 2024 · 6 min · dynamic-programming · leetcode · math · Last updated: Aug 2, 2025

Number of Ways to Build Sturdy Brick Wall

November 27, 2024 · 9 min · array · bit-manipulation · bitmask · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Order Two Columns Independently

November 27, 2024 · 2 min · database · leetcode · Last updated: Aug 2, 2025

Paths in Maze That Lead to Same Room

November 27, 2024 · 5 min · graph · leetcode · Last updated: Aug 2, 2025

Pour Water Between Buckets to Make Water Levels Equal

November 27, 2024 · 7 min · array · binary-search · leetcode · Last updated: Aug 2, 2025

Product Sales Analysis IV

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Remove All Ones With Row and Column Flips

November 27, 2024 · 5 min · array · bit-manipulation · leetcode · math · matrix · Last updated: Aug 2, 2025

Sort Linked List Already Sorted Using Absolute Values

November 27, 2024 · 10 min · leetcode · linked-list · sorting · two-pointers · Last updated: Aug 2, 2025

Sort the Olympic Table

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Substrings That Begin and End With the Same Letter

November 27, 2024 · 4 min · counting · hash-table · leetcode · math · prefix-sum · string · Last updated: Aug 2, 2025

Subtree Removal Game with Fibonacci Tree

November 27, 2024 · 3 min · binary-tree · dynamic-programming · game-theory · leetcode · math · tree · Last updated: Jul 26, 2025

Tasks Count in the Weekend

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

The Airport With the Most Traffic

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

The Category of Each Member in the Store

November 27, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

The Change in Global Rankings

November 27, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

The First Day of the Maximum Recorded Degree in Each City

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

The Number of Passengers in Each Bus I

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

The Number of Passengers in Each Bus II

November 27, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

The Number of Seniors and Juniors to Join the Company

November 27, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

The Number of Seniors and Juniors to Join the Company II

November 27, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

The Users That Are Eligible for Discount

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Valid Palindrome 4 - is string palindrome after at most 2 char replacement

November 27, 2024 · 2 min · leetcode · palindrome · string · two-pointers · Last updated: Aug 2, 2025

Active Users

November 27, 2024 · 4 min · database · leetcode · Last updated: Jun 28, 2025

All the Pairs With the Maximum Number of Common Followers

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

All Valid Triplets That Can Represent a Country

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Bank Account Summary

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Binary Searchable Numbers in an Unsorted Array

November 27, 2024 · 6 min · array · binary-search · leetcode · Last updated: Aug 2, 2025

Change the Root of a Binary Tree

November 27, 2024 · 5 min · binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Check if String Is Decomposable Into Value-Equal Substrings

November 27, 2024 · 5 min · leetcode · string · Last updated: Jul 4, 2025

Clone N-ary Tree

November 27, 2024 · 5 min · breadth-first-search · depth-first-search · hash-table · leetcode · tree · Last updated: Jul 6, 2025

Count Apples and Oranges

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Count Nodes Equal to Sum of Descendants

November 27, 2024 · 5 min · binary-tree · depth-first-search · leetcode · tree · Last updated: Jul 26, 2025

Count Pairs of Equal Substrings With Minimum Difference

November 27, 2024 · 1 min · greedy · hash-table · leetcode · string · Last updated: Aug 2, 2025

Counting Elements

November 27, 2024 · 3 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

Countries You Can Safely Invest In

November 27, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

Cutting Ribbons

November 27, 2024 · 6 min · array · binary-search · leetcode · Last updated: Aug 2, 2025

Delete N Nodes After M Nodes of a Linked List

November 27, 2024 · 5 min · leetcode · linked-list · Last updated: Aug 2, 2025

Design an Expression Tree With Evaluate Function

November 27, 2024 · 5 min · array · binary-tree · design · leetcode · math · stack · tree · Last updated: Aug 2, 2025

Design Most Recently Used Queue

November 27, 2024 · 4 min · array · binary-indexed-tree · design · hash-table · leetcode · ordered-set · stack · Last updated: Aug 2, 2025

Dot Product of Two Sparse Vectors

November 27, 2024 · 3 min · array · design · hash-table · leetcode · two-pointers · Last updated: Aug 2, 2025

Faulty Sensor

November 27, 2024 · 6 min · array · leetcode · two-pointers · Last updated: Aug 2, 2025

Find Customers With Positive Revenue this Year

November 27, 2024 · 2 min · database · leetcode · Last updated: Aug 2, 2025

Find Interview Candidates

November 27, 2024 · 6 min · database · leetcode · Last updated: Aug 2, 2025

Find Root of N-Ary Tree

November 27, 2024 · 4 min · bit-manipulation · depth-first-search · hash-table · leetcode · tree · Last updated: Aug 2, 2025

First and Last Call On the Same Day

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Fix Product Name Format

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Grand Slam Titles

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Group Employees of the Same Salary

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Guess the Majority in a Hidden Array

November 27, 2024 · 9 min · array · interactive · leetcode · math · Last updated: Aug 2, 2025

Hopper Company Queries I

November 27, 2024 · 7 min · database · leetcode · Last updated: Jul 26, 2025

Hopper Company Queries II

November 27, 2024 · 8 min · database · leetcode · Last updated: Jul 26, 2025

Hopper Company Queries III

November 27, 2024 · 7 min · database · leetcode · Last updated: Jul 26, 2025

Kth Smallest Subarray Sum

November 27, 2024 · 6 min · array · binary-search · leetcode · sliding-window · Last updated: Aug 2, 2025

League Statistics

November 27, 2024 · 6 min · database · leetcode · Last updated: Aug 2, 2025

Leetcodify Friends Recommendations

November 27, 2024 · 6 min · database · leetcode · Last updated: Aug 2, 2025

Leetcodify Similar Friends

November 27, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

Leftmost Column with at Least a One

November 27, 2024 · 5 min · array · binary-search · interactive · leetcode · matrix · Last updated: Aug 2, 2025

Longest Word With All Prefixes

November 27, 2024 · 7 min · depth-first-search · leetcode · trie · Last updated: Aug 2, 2025

Maximize the Beauty of the Garden

November 27, 2024 · 6 min · array · greedy · hash-table · leetcode · prefix-sum · Last updated: Aug 2, 2025

Maximum Number of Accepted Invitations

November 27, 2024 · 6 min · array · depth-first-search · graph · leetcode · matrix · Last updated: Aug 2, 2025

Maximum Number of People That Can Be Caught in Tag

November 27, 2024 · 6 min · array · greedy · leetcode · Last updated: Aug 2, 2025

Maximum Transaction Each Day

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Minimize Product Sum of Two Arrays

November 27, 2024 · 3 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Move Sub-Tree of N-Ary Tree

November 27, 2024 · 5 min · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Next Palindrome Using Same Digits

November 27, 2024 · 6 min · leetcode · string · two-pointers · Last updated: Aug 2, 2025

NPV Queries

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Number of Calls Between Two Persons

November 27, 2024 · 2 min · database · leetcode · Last updated: Aug 2, 2025

Number of Distinct Substrings in a String

November 27, 2024 · 4 min · hash-function · leetcode · rolling-hash · string · suffix-array · trie · Last updated: Aug 2, 2025

Page Recommendations II

November 27, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

Product’s Price for Each Store

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Product’s Worth Over Invoices

November 27, 2024 · 4 min · database · leetcode · Last updated: Jul 26, 2025

Put Boxes Into the Warehouse I

November 27, 2024 · 5 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Put Boxes Into the Warehouse II

November 27, 2024 · 6 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Rectangles Area

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Sales by Day of the Week

November 27, 2024 · 6 min · database · leetcode · Last updated: Aug 2, 2025

Sellers With No Sales

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Shortest Path in a Hidden Grid

November 27, 2024 · 6 min · breadth-first-search · depth-first-search · graph · interactive · leetcode · Last updated: Aug 2, 2025

Shortest Path to Get Food

November 27, 2024 · 3 min · array · breadth-first-search · leetcode · matrix · Last updated: Aug 2, 2025

Smallest Greater Multiple Made of Two Digits

November 27, 2024 · 4 min · enumeration · leetcode · math · Last updated: Aug 2, 2025

Strings Differ by One Character

November 27, 2024 · 4 min · hash-function · hash-table · leetcode · rolling-hash · string · Last updated: Aug 2, 2025

Strong Friendship

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Sum Of Special Evenly-Spaced Elements In Array

November 27, 2024 · 6 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

The Most Recent Orders for Each Product

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

The Most Similar Path in a Graph

November 27, 2024 · 9 min · dynamic-programming · graph · leetcode · Last updated: Aug 2, 2025

Unique Orders and Customers Per Month

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Warehouse Manager

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Widest Pair of Indices With Equal Range Sum

November 27, 2024 · 5 min · array · hash-table · leetcode · prefix-sum · Last updated: Aug 2, 2025

Capital Gain-Loss

November 27, 2024 · 4 min · array · counting · database · hash-table · leetcode · Last updated: Jul 1, 2025

Activity Participants

November 27, 2024 · 3 min · database · leetcode · Last updated: Jun 28, 2025

Ads Performance

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Array Transformation

November 27, 2024 · 3 min · array · leetcode · simulation · Last updated: Aug 2, 2025

Design A Leaderboard

November 27, 2024 · 3 min · design · hash-table · leetcode · sorting · Last updated: Aug 2, 2025

Encode Number

November 27, 2024 · 3 min · bit-manipulation · leetcode · math · string · Last updated: Aug 2, 2025

Find the Start and End Number of Continuous Ranges

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Get the Second Most Recent Activity

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Handshakes That Don’t Cross

November 27, 2024 · 4 min · dynamic-programming · leetcode · math · Last updated: Aug 2, 2025

Number of Comments per Post

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Number of Trusted Contacts of a Customer

November 27, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

Palindrome Removal

November 27, 2024 · 6 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Remove Interval

November 27, 2024 · 5 min · array · leetcode · Last updated: Aug 2, 2025

Smallest Common Region

November 27, 2024 · 3 min · array · breadth-first-search · depth-first-search · hash-table · leetcode · string · tree · Last updated: Aug 2, 2025

Students With Invalid Departments

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Synonymous Sentences

November 27, 2024 · 7 min · array · backtracking · hash-table · leetcode · string · union-find · Last updated: Aug 2, 2025

Total Sales Amount by Year

November 27, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

Tree Diameter

November 27, 2024 · 5 min · breadth-first-search · depth-first-search · graph · leetcode · topological-sort · tree · Last updated: Aug 2, 2025

Meeting Scheduler

November 27, 2024 · 5 min · array · leetcode · sorting · two-pointers · Last updated: Aug 2, 2025

Stepping Numbers

November 27, 2024 · 6 min · backtracking · breadth-first-search · leetcode · math · Last updated: Jul 26, 2025

Team Scores in Football Tournament

November 27, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

Toss Strange Coins

November 27, 2024 · 2 min · array · dynamic-programming · leetcode · math · probability-and-statistics · Last updated: Aug 2, 2025

Two Sum BSTs

November 27, 2024 · 2 min · binary-search · binary-search-tree · binary-tree · depth-first-search · leetcode · stack · tree · two-pointers · Last updated: Aug 2, 2025

Analyze User Website Visit Pattern

November 27, 2024 · 9 min · array · hash-table · leetcode · sorting · Last updated: Aug 2, 2025

Armstrong Number

November 27, 2024 · 2 min · leetcode · math · Last updated: Aug 2, 2025

Article Views II

November 27, 2024 · 2 min · database · leetcode · Last updated: Aug 2, 2025

Check If a Number Is Majority Element in a Sorted Array

November 27, 2024 · 7 min · array · binary-search · leetcode · Last updated: Jul 3, 2025

Connecting Cities With Minimum Cost

November 27, 2024 · 6 min · graph · heap-priority-queue · leetcode · minimum-spanning-tree · union-find · Last updated: Jul 7, 2025

Design Bounded Blocking Queue

November 27, 2024 · 5 min · concurrency · leetcode · Last updated: Aug 2, 2025

Design File System

November 27, 2024 · 8 min · design · hash-table · leetcode · string · trie · Last updated: Aug 2, 2025

Diet Plan Performance

November 27, 2024 · 6 min · array · leetcode · sliding-window · Last updated: Aug 2, 2025

Find Smallest Common Element in All Rows

November 27, 2024 · 4 min · array · binary-search · counting · hash-table · leetcode · matrix · Last updated: Aug 2, 2025

Market Analysis II

November 27, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

Minimum Time to Build Blocks

November 27, 2024 · 5 min · array · greedy · heap-priority-queue · leetcode · math · Last updated: Aug 2, 2025

New Users Daily Count

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Number of Days in a Month

November 27, 2024 · 3 min · leetcode · math · Last updated: Aug 2, 2025

Optimize Water Distribution in a Village

November 27, 2024 · 7 min · graph · heap-priority-queue · leetcode · minimum-spanning-tree · union-find · Last updated: Aug 2, 2025

Remove Vowels from a String

November 27, 2024 · 2 min · leetcode · string · Last updated: Aug 2, 2025

Reported Posts

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Reported Posts II

November 27, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

Single-Row Keyboard

November 27, 2024 · 3 min · hash-table · leetcode · string · Last updated: Aug 2, 2025

String Transforms Into Another String

November 27, 2024 · 4 min · hash-table · leetcode · string · Last updated: Aug 2, 2025

The Earliest Moment When Everyone Become Friends

November 27, 2024 · 5 min · array · leetcode · sorting · union-find · Last updated: Aug 2, 2025

All Paths from Source Lead to Destination

November 27, 2024 · 6 min · graph · leetcode · topological-sort · Last updated: Aug 2, 2025

Campus Bikes

November 27, 2024 · 7 min · array · greedy · leetcode · sorting · Last updated: Jul 1, 2025

Confusing Number

November 27, 2024 · 4 min · leetcode · math · Last updated: Jul 7, 2025

Digit Count in Range

November 27, 2024 · 3 min · dynamic-programming · leetcode · math · Last updated: Aug 2, 2025

Find fixed point in sorted array

November 27, 2024 · 6 min · array · binary-search · leetcode · divide-n-conquer · daily-coding-problem · array-algo · Last updated: Aug 11, 2025

Find K-Length Substrings With No Repeated Characters

November 27, 2024 · 5 min · array · binary-search · binary-tree · breadth-first-search · depth-first-search · hash-table · heap-priority-queue · leetcode · math · matrix · simulation · sliding-window · sorting · string · tree · union-find · Last updated: Aug 2, 2025

Index Pairs of a String

November 27, 2024 · 7 min · array · leetcode · sorting · string · trie · Last updated: Aug 2, 2025

Missing Element in Sorted Array

November 27, 2024 · 5 min · array · binary-search · leetcode · Last updated: Aug 2, 2025

Project Employees II

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Shortest Distance After Road Addition Queries I

November 27, 2024 · 5 min · array · breadth-first-search · graph · leetcode · Last updated: Aug 2, 2025

Similar RGB Color

November 27, 2024 · 3 min · enumeration · leetcode · math · string · Last updated: Aug 2, 2025

Split BST

November 27, 2024 · 2 min · binary-search-tree · binary-tree · leetcode · recursion · tree · Last updated: Jul 26, 2025

Pour Water

November 27, 2024 · 7 min · array · leetcode · simulation · Last updated: Aug 2, 2025

IP to CIDR

November 27, 2024 · 7 min · bit-manipulation · leetcode · string · Last updated: Aug 2, 2025

Candy Crush

November 27, 2024 · 10 min · array · leetcode · matrix · simulation · two-pointers · Last updated: Jul 1, 2025

Number of Distinct Islands II

November 27, 2024 · 6 min · breadth-first-search · depth-first-search · hash-function · hash-table · leetcode · union-find · Last updated: Aug 2, 2025

Search in a Sorted Array of Unknown Size

November 27, 2024 · 5 min · array · binary-search · interactive · leetcode · Last updated: Aug 2, 2025

K Empty Slots

November 27, 2024 · 7 min · array · binary-indexed-tree · heap-priority-queue · leetcode · monotonic-queue · ordered-set · queue · segment-tree · sliding-window · Last updated: Aug 2, 2025

Path Sum IV

November 27, 2024 · 4 min · array · binary-tree · depth-first-search · hash-table · leetcode · tree · Last updated: Aug 2, 2025

Remove 9

November 27, 2024 · 3 min · leetcode · math · Last updated: Aug 2, 2025

Average Salary - Departments VS Company

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Minimum Factorization

November 27, 2024 · 5 min · greedy · leetcode · math · Last updated: Aug 2, 2025

Students Report By Geography

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Shortest Distance in a Plane

November 27, 2024 · 3 min · database · leetcode · Last updated: Jul 26, 2025

Design Compressed String Iterator

November 27, 2024 · 6 min · array · design · iterator · leetcode · string · Last updated: Aug 2, 2025

Design In-Memory File System

November 27, 2024 · 10 min · design · hash-table · leetcode · sorting · string · trie · Last updated: Aug 2, 2025

Friend Requests II - Who Has the Most Friends

November 27, 2024 · 3 min · database · leetcode · Last updated: Jul 12, 2025

Find Cumulative Salary of an Employee

November 27, 2024 · 5 min · database · leetcode · Last updated: Aug 2, 2025

Get Highest Answer Rate Question

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Kill Process

November 27, 2024 · 4 min · array · breadth-first-search · depth-first-search · hash-table · leetcode · tree · Last updated: Aug 2, 2025

Median Employee Salary

November 27, 2024 · 4 min · database · leetcode · Last updated: Aug 2, 2025

Squirrel Simulation

November 27, 2024 · 3 min · array · leetcode · math · Last updated: Jul 27, 2025

Winning Candidate

November 27, 2024 · 3 min · database · leetcode · Last updated: Aug 2, 2025

Longest Line of Consecutive One in Matrix

November 27, 2024 · 6 min · array · dynamic-programming · leetcode · matrix · Last updated: Aug 2, 2025

Binary Tree Longest Consecutive Sequence II

November 27, 2024 · 7 min · binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Construct Binary Tree from String

November 27, 2024 · 7 min · binary-tree · depth-first-search · leetcode · stack · string · tree · Last updated: Jul 7, 2025

Lonely Pixel I

November 27, 2024 · 5 min · array · hash-table · leetcode · matrix · Last updated: Aug 2, 2025

Find Permutation

November 27, 2024 · 4 min · array · greedy · leetcode · stack · string · Last updated: Aug 2, 2025

Smallest Good Base Problem

November 26, 2024 · 4 min · binary-search · leetcode · math · search/binary · Last updated: Nov 26, 2024

Binary Tree Path Sum - Find all paths between any two nodes value

November 26, 2024 · 3 min · leetcode · backtracking · ctci · binary-tree · bt-binary-tree · path-finding · pathsum · binary-tree-path · Last updated: Aug 2, 2025

Binary Tree Path Sum - Maximum between any two leaves

November 26, 2024 · 4 min · bt-binary-tree · path-finding · pathsum · traversal/postorder · binary-tree-path · binary-tree-leaf · Last updated: Aug 2, 2025

Binary Tree Path Sum - Maximum Sum Leaf to Root path

November 26, 2024 · 3 min · bt-binary-tree · path-finding · pathsum · binary-tree-path · binary-tree-leaf · dfs · Last updated: Aug 2, 2025

Binary Tree Path Sum - Maximum Sum Root to Leaf path

November 26, 2024 · 3 min · bt-binary-tree · path-finding · pathsum · binary-tree-path · binary-tree-leaf · dfs · Last updated: Aug 2, 2025

Binary Tree Path Sum - Minimum Sum Root to Leaf path

November 26, 2024 · 3 min · bt-binary-tree · path-finding · pathsum · binary-tree-path · binary-tree-leaf · dfs · daily-coding-problem · Last updated: Aug 2, 2025

Brick Wall

November 26, 2024 · 5 min · array · hash-table · hashing · leetcode · Last updated: Aug 9, 2025

Check if Tree is Full Binary Tree

November 26, 2024 · 2 min · full-binary-tree · binary-tree · Last updated: Aug 2, 2025

Check if two binary trees are mirror images of each other

November 26, 2024 · 3 min · bt-binary-tree · mirror · Last updated: Aug 2, 2025

Check if two nodes in a binary tree are siblings

November 26, 2024 · 3 min · bt-binary-tree · Last updated: Aug 2, 2025

Closest leaf to root in a binary tree

November 26, 2024 · 3 min · bt-binary-tree · longest · path-finding · pathsum · binary-tree-path · binary-tree-leaf · daily-coding-problem · Last updated: Aug 2, 2025

Consecutive Numbers Sum

November 26, 2024 · 3 min · count · enumeration · leetcode · math · Last updated: Aug 1, 2025

Construct ancestor matrix from a binary tree

November 26, 2024 · 4 min · matrix · tree-ds · Last updated: Aug 2, 2025

Construct binary tree from an ancestor matrix

November 26, 2024 · 5 min · matrix · tree-ds · Last updated: Aug 2, 2025

Convert binary tree to its Sum tree

November 26, 2024 · 4 min · convert · bt-binary-tree · Last updated: Aug 2, 2025

Convert Heap ordered Linked List to Binary Tree

November 26, 2024 · 5 min · convert · linkedlist · bt-binary-tree · Last updated: Aug 2, 2025

Delete a binary tree completely

November 26, 2024 · 3 min · bt-binary-tree · traversal/postorder · Last updated: Aug 2, 2025

Diameter Of a N-Ary Tree

November 26, 2024 · 4 min · depth-first-search · dfs · interviewbit · leetcode · n-ary-tree · tree · Last updated: Aug 2, 2025

Distance between two nodes in binary tree

November 26, 2024 · 7 min · binary-tree · breadth-first-search · bt-binary-tree · depth-first-search · distance · hash-table · leetcode · tree · Last updated: Aug 2, 2025

Find distance from root to given node in binary tree

November 26, 2024 · 3 min · bt-binary-tree · distance · Last updated: Aug 2, 2025

Find path from root to given node in a binary tree

November 26, 2024 · 4 min · bt-binary-tree · Last updated: Aug 2, 2025

Flatten Binary Search Tree to Circular Doubly Linked List

November 26, 2024 · 4 min · convert · linkedlist · bt-binary-tree · Last updated: Aug 2, 2025

Flatten Binary tree to double linked list in-place

November 26, 2024 · 8 min · todo · conversion · convert · bt-binary-tree · doubly-linked-list · Last updated: Aug 2, 2025

Height of a Tree Definition

November 26, 2024 · 1 min · Last updated: Aug 2, 2025

Implement queue using resizing array

November 26, 2024 · 4 min · queue · dynamic-memory · Last updated: Aug 2, 2025

Improve search in BST with sentinel

November 26, 2024 · 6 min · bt-binary-tree · Last updated: Aug 2, 2025

Inorder predecessor and successor of a node in binary search tree

November 26, 2024 · 6 min · todo · bst-binary-search-tree · traversal · traversal/inorder · daily-coding-problem · Last updated: Aug 2, 2025

Is Graph Bipartite

November 26, 2024 · 11 min · bipartite · breadth-first-search · depth-first-search · graph · leetcode · union-find · Last updated: Aug 2, 2025

Minimize Malware Spread

November 26, 2024 · 8 min · array · breadth-first-search · depth-first-search · graph · hash-table · leetcode · union-find · Last updated: Aug 2, 2025

Minimum Number Of Platforms For Train Station

November 26, 2024 · 3 min · interval · Last updated: Aug 2, 2025

Optimal binary search tree construction for minimum search cost

November 26, 2024 · 4 min · bst-binary-search-tree · Last updated: Aug 2, 2025

Partition Array for Maximum Sum Problem

November 26, 2024 · 4 min · array · dynamic-programming · leetcode · todo · Last updated: Nov 27, 2024

Range Max Query

November 26, 2024 · 5 min · tree-ds · rmq-range-minimum-query · Last updated: Aug 2, 2025

Range Module

November 26, 2024 · 5 min · design · leetcode · ordered-set · segment-tree · todo · Last updated: Aug 2, 2025

Rectangle Overlap

November 26, 2024 · 4 min · geometry · java · leetcode · math · rectangle · Last updated: Aug 2, 2025

Remove Boxes

November 26, 2024 · 12 min · array · dynamic-programming · leetcode · memoization · Last updated: Aug 3, 2025

Reverse Pairs

November 26, 2024 · 3 min · array · binary-indexed-tree · binary-search · divide-and-conquer · leetcode · merge-sort · ordered-set · segment-tree · todo · Last updated: Aug 2, 2025

Robot Room Cleaner

November 26, 2024 · 5 min · backtracking · interactive · leetcode · Last updated: Aug 2, 2025

Shortest Unique Prefix

November 26, 2024 · 3 min · interviewbit · trie · daily-coding-problem · Last updated: Aug 2, 2025

Subarray Product Less Than K

November 26, 2024 · 4 min · array · binary-search · count · dynamic-programming · leetcode · prefix-sum · product · sliding-window · subarray · Last updated: Aug 2, 2025

Target Sum

November 26, 2024 · 7 min · array · backtracking · dynamic-programming · leetcode · video · Last updated: Aug 2, 2025

The Maze 1

November 26, 2024 · 4 min · array · breadth-first-search · depth-first-search · leetcode · matrix · Last updated: Jul 31, 2025

The Maze 2

November 26, 2024 · 9 min · array · breadth-first-search · depth-first-search · graph · heap-priority-queue · leetcode · matrix · shortest-path · Last updated: Jul 31, 2025

The Maze 3

November 26, 2024 · 6 min · array · breadth-first-search · depth-first-search · graph · heap-priority-queue · leetcode · matrix · shortest-path · string · Last updated: Jul 31, 2025

Transformations Between Binary Tree Structuctures and Linked Lists

November 26, 2024 · 1 min · convert · linkedlist · bt-binary-tree · todo · Last updated: Aug 2, 2025

Binary Tree Path - All root to leaf paths

November 26, 2024 · 2 min · backtracking · binary-tree · binary-tree-leaf · binary-tree-path · bt-binary-tree · depth-first-search · leetcode · path-finding · string · todo · tree · Last updated: Aug 2, 2025

Closest Binary Search Tree Value

November 26, 2024 · 4 min · binary-search · binary-search-tree · binary-tree · bst-binary-search-tree · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Closest Binary Search Tree Value II

November 26, 2024 · 3 min · binary-search-tree · binary-tree · depth-first-search · heap-priority-queue · leetcode · stack · tree · two-pointers · Last updated: Aug 2, 2025

Count distinct binary trees for a given number of nodes

November 26, 2024 · 4 min · binary-tree · count · Last updated: Aug 2, 2025

Employee Free Time

November 26, 2024 · 6 min · array · heap-priority-queue · interviewbit · leetcode · sorting · Last updated: Aug 1, 2025

Height and Depth of a Node in Tree

November 26, 2024 · 1 min · Last updated: Aug 2, 2025

Maximum CPU Load For Running Tasks

November 26, 2024 · 3 min · interviewbit · interval · Last updated: Aug 2, 2025

Replace the Substring for Balanced String

November 26, 2024 · 4 min · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Validate Binary Tree Nodes

November 26, 2024 · 4 min · binary-tree · breadth-first-search · depth-first-search · graph · leetcode · math · tree · union-find · Last updated: Aug 2, 2025

Find Champion II

November 26, 2024 · 4 min · graph · leetcode · Last updated: Aug 2, 2025

Sliding Puzzle

November 25, 2024 · 5 min · array · backtracking · breadth-first-search · dynamic-programming · leetcode · matrix · memoization · Last updated: Aug 2, 2025

Maximum Matrix Sum

November 24, 2024 · 5 min · array · database · dynamic-programming · graph · greedy · leetcode · math · matrix · number-theory · shortest-path · string · suffix-array · topological-sort · Last updated: Aug 2, 2025

Implement circular stack

November 24, 2024 · 4 min · Last updated: Aug 2, 2025

Rotating the Box

November 23, 2024 · 3 min · array · binary-search · leetcode · math · matrix · prefix-sum · two-pointers · Last updated: Aug 2, 2025

Flip Columns For Maximum Number of Equal Rows

November 22, 2024 · 3 min · array · hash-table · leetcode · math · matrix · Last updated: Aug 2, 2025

Count Unguarded Cells in the Grid

November 21, 2024 · 5 min · array · binary-indexed-tree · binary-search · binary-tree · breadth-first-search · counting · depth-first-search · divide-and-conquer · dynamic-programming · enumeration · greedy · hash-function · hash-table · leetcode · math · matrix · merge-sort · number-theory · ordered-set · prefix-sum · rolling-hash · segment-tree · simulation · sliding-window · sorting · stack · string · tree · trie · Last updated: Aug 2, 2025

Take K of Each Character From Left and Right

November 20, 2024 · 4 min · hash-table · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Maximum Sum of Distinct Subarrays With Length K

November 19, 2024 · 4 min · array · hash-table · heap-priority-queue · leetcode · simulation · sliding-window · two-pointers · Last updated: Aug 2, 2025

Defuse the Bomb

November 18, 2024 · 3 min · array · leetcode · sliding-window · Last updated: Aug 2, 2025

Shortest Subarray with Sum at Least K

November 17, 2024 · 3 min · array · binary-search · heap-priority-queue · leetcode · monotonic-queue · prefix-sum · queue · sliding-window · Last updated: Aug 2, 2025

Find the Power of K-Size Subarrays 1

November 16, 2024 · 3 min · array · backtracking · binary-search · binary-tree · bit-manipulation · bitmask · breadth-first-search · combinatorics · counting · database · depth-first-search · doubly-linked-list · dynamic-programming · enumeration · game-theory · graph · greedy · hash-function · hash-table · heap-priority-queue · leetcode · linked-list · math · matrix · number-theory · prefix-sum · recursion · rolling-hash · segment-tree · shortest-path · simulation · sliding-window · sorting · string · string-matching · tree · trie · two-pointers · Last updated: Aug 2, 2025

Shortest Subarray to be Removed to Make Array Sorted

November 15, 2024 · 3 min · array · binary-search · leetcode · monotonic-stack · stack · two-pointers · Last updated: Aug 2, 2025

Minimized Maximum of Products Distributed to Any Store

November 14, 2024 · 4 min · array · backtracking · binary-search · counting · database · design · graph · greedy · hash-table · leetcode · prefix-sum · search/binary · simulation · string · Last updated: Aug 2, 2025

Count the Number of Fair Pairs

November 13, 2024 · 4 min · array · binary-search · bit-manipulation · bitmask · brainteaser · breadth-first-search · depth-first-search · dynamic-programming · graph · greedy · hash-table · heap-priority-queue · leetcode · math · matrix · prefix-sum · search/binary · segment-tree · shortest-path · simulation · sorting · string · tree · two-pointers · union-find · Last updated: Aug 2, 2025

Two Best Non-Overlapping Events

November 12, 2024 · 4 min · array · backtracking · binary-search · dynamic-programming · heap-priority-queue · leetcode · prefix-sum · simulation · sorting · string · todo · Last updated: Aug 2, 2025

Maximum Earnings From Taxi

November 12, 2024 · 4 min · array · binary-search · database · dynamic-programming · hash-table · leetcode · simulation · sliding-window · sorting · string · Last updated: Aug 2, 2025

Most Beautiful Item for Each Query

November 12, 2024 · 4 min · array · binary-search · greedy · leetcode · monotonic-queue · queue · sorting · Last updated: Aug 2, 2025

Maximum XOR for Each Query

November 8, 2024 · 5 min · array · bit-manipulation · bits · combinatorics · database · leetcode · math · prefix-sum · string · video · Last updated: Aug 2, 2025

Largest Combination With Bitwise AND Greater Than Zero

November 7, 2024 · 6 min · array · bit-manipulation · bits · breadth-first-search · counting · depth-first-search · design · hash-table · leetcode · ordered-set · segment-tree · string · tree · video · Last updated: Aug 2, 2025

Find if Array Can Be Sorted

November 6, 2024 · 5 min · array · bit-manipulation · bits · breadth-first-search · bubble · graph · greedy · hash-table · heap-priority-queue · leetcode · math · number-theory · prefix-sum · sliding-window · sorting · string · video · Last updated: Aug 2, 2025

Minimum Number of Changes to Make Binary String Beautiful

November 5, 2024 · 4 min · array · binary-indexed-tree · binary-search · binary-string · bit-manipulation · combinatorics · database · depth-first-search · dynamic-programming · enumeration · graph · greedy · hash-table · heap-priority-queue · interactive · leetcode · math · matrix · segment-tree · sliding-window · sorting · string · video · Last updated: Aug 2, 2025

Consecutive Characters

November 5, 2024 · 2 min · leetcode · math · number-theory · string · Last updated: Aug 2, 2025

String Compression 3

November 4, 2024 · 3 min · array · backtracking · binary-indexed-tree · binary-search · bit-manipulation · breadth-first-search · combinatorics · compression · counting · counting-sort · database · depth-first-search · divide-and-conquer · dynamic-programming · enumeration · graph · greedy · hash-table · heap-priority-queue · leetcode · math · matrix · monotonic-stack · prefix-sum · queue · segment-tree · simulation · sliding-window · sorting · stack · string · suffix-array · tree · two-pointers · video · Last updated: Aug 2, 2025

Capitalize the Title

November 4, 2024 · 3 min · leetcode · linked-list · stack · string · two-pointers · Last updated: Aug 2, 2025

Extended Euclidean Algorithm using modulo operator

November 3, 2024 · 3 min · numerical-algo · Last updated: Aug 2, 2025

Basic Euclidean Algorithm to find GCD of two numbers using modulo operator

November 3, 2024 · 2 min · Last updated: Aug 2, 2025

Subtractive Euclidean Algorithm to find GCD of two numbers

November 3, 2024 · 3 min · Last updated: Aug 2, 2025

Binary to Decimal Conversion

November 3, 2024 · 2 min · Last updated: Nov 3, 2024

Circular Sentence

November 2, 2024 · 4 min · leetcode · string · video · Last updated: Aug 2, 2025

Delete Characters to Make Fancy String

November 1, 2024 · 4 min · count · leetcode · string · todo · video · Last updated: Jul 21, 2025

October ²⁹

Row With Maximum Ones

October 31, 2024 · 2 min · array · binary-matrix · depth-first-search · dynamic-programming · graph · greedy · leetcode · math · matrix · stack · string · tree · Last updated: Aug 2, 2025

Minimum Total Distance Traveled

October 31, 2024 · 10 min · array · dynamic-programming · hash-table · leetcode · math · number-theory · sorting · two-pointers · Last updated: Aug 2, 2025

Maximum Number of Moves in a Grid

October 29, 2024 · 8 min · array · binary-tree · breadth-first-search · database · depth-first-search · dynamic-programming · graph · leetcode · matrix · todo · tree · union-find · Last updated: Aug 2, 2025

Longest Square Streak in an Array

October 28, 2024 · 4 min · array · binary-search · binary-tree · bit-manipulation · brainteaser · breadth-first-search · combinatorics · counting · database · design · dynamic-programming · graph · hash-table · heap-priority-queue · leetcode · math · matrix · number-theory · search/binary · simulation · sorting · string · todo · tree · two-pointers · union-find · video · Last updated: Aug 2, 2025

Count Square Submatrices with All Ones

October 27, 2024 · 7 min · array · binary-matrix · dynamic-programming · leetcode · matrix · recursion · todo · Last updated: Aug 2, 2025

Height of Binary Tree After Subtree Removal Queries

October 26, 2024 · 9 min · array · binary-tree · breadth-first-search · bt-binary-tree · depth-first-search · dfs · greedy · leetcode · simulation · sorting · todo · tree · two-pointers · video · Last updated: Aug 2, 2025

Remove Sub-Folders from the Filesystem

October 25, 2024 · 6 min · array · depth-first-search · leetcode · sorting · string · todo · trie · video · Last updated: Aug 2, 2025

Diagonal Traverse

October 22, 2024 · 3 min · array · leetcode · matrix · simulation · Last updated: Aug 2, 2025

Kth Largest Sum in a Binary Tree

October 22, 2024 · 7 min · array · bfs · binary-search · binary-tree · bit-manipulation · breadth-first-search · bt-binary-tree · counting · depth-first-search · design · dynamic-programming · greedy · hash-table · heap-priority-queue · leetcode · math · matrix · number-theory · prefix-sum · simulation · sorting · stack · string · traversal/level-order · tree · two-pointers · video · Last updated: Aug 2, 2025

Split a String Into the Max Number of Unique Substrings

October 21, 2024 · 4 min · backtracking · hash-table · hashmap · leetcode · string · video · Last updated: Aug 2, 2025

Parsing A Boolean Expression

October 20, 2024 · 4 min · array · database · leetcode · prefix-sum · recursion · stack · string · Last updated: Aug 10, 2025

Find Kth Bit in Nth Binary String

October 19, 2024 · 4 min · array · bits · greedy · hash-table · leetcode · prefix-sum · recursion · simulation · string · Last updated: Aug 2, 2025

Count Number of Maximum Bitwise-OR Subsets

October 18, 2024 · 6 min · array · backtracking · bit-manipulation · bits · enumeration · leetcode · video · Last updated: Jul 28, 2025

Maximum Swap

October 17, 2024 · 7 min · greedy · leetcode · math · maths · video · Last updated: Aug 2, 2025

Separate Black and White Balls

October 15, 2024 · 3 min · array · binary-indexed-tree · binary-search · bit-manipulation · combinatorics · counting · depth-first-search · dynamic-programming · enumeration · graph · greedy · hash-table · heap-priority-queue · leetcode · math · matrix · monotonic-queue · monotonic-stack · number-theory · partition · prefix-sum · queue · segment-tree · shortest-path · simulation · sliding-window · sorting · stack · string · tree · two-pointers · union-find · video · Last updated: Aug 2, 2025

Maximal Score After Applying K Operations

October 14, 2024 · 4 min · array · binary-search · combinatorics · counting · depth-first-search · dynamic-programming · greedy · hash-table · heap-priority-queue · heap/max · leetcode · math · matrix · prefix-sum · queue · simulation · sliding-window · string · tree · two-pointers · video · Last updated: Aug 2, 2025

Divide Intervals Into Minimum Number of Groups

October 12, 2024 · 4 min · array · binary-indexed-tree · binary-search · binary-tree · bit-manipulation · breadth-first-search · depth-first-search · design · divide-and-conquer · dynamic-programming · greedy · hash-table · heap-priority-queue · interval · leetcode · math · monotonic-queue · number-theory · prefix-sum · queue · segment-tree · sliding-window · sorting · string · todo · tree · two-pointers · Last updated: Aug 2, 2025

The Number of the Smallest Unoccupied Chair

October 11, 2024 · 8 min · array · hash-table · heap · heap-priority-queue · leetcode · monotonic-stack · prefix-sum · sorting · stack · video · Last updated: Aug 2, 2025

Maximum Width Ramp

October 10, 2024 · 8 min · array · leetcode · monotonic-stack · sorting · stack · stack/monotonic · todo · two-pointers · Last updated: Aug 2, 2025

Minimum Add to Make Parentheses Valid

October 9, 2024 · 4 min · count · greedy · leetcode · stack · string · todo · video · Last updated: Aug 2, 2025

Minimum String Length After Removing Substrings

October 7, 2024 · 6 min · backtracking · greedy · leetcode · math · simulation · stack · string · todo · two-pointers · video · Last updated: Aug 2, 2025

Sentence Similarity

October 6, 2024 · 4 min · array · hash-table · leetcode · string · Last updated: Aug 10, 2025

Sentence Similarity 2 - with transitive word pairs

October 6, 2024 · 4 min · array · breadth-first-search · depth-first-search · hash-table · leetcode · string · union-find · Last updated: Aug 2, 2025

Sentence Similarity 3 - By Insertion

October 6, 2024 · 4 min · array · leetcode · string · two-pointers · Last updated: Aug 2, 2025

3Sum Smaller

October 5, 2024 · 2 min · array · binary-search · leetcode · sorting · todo · two-pointers · Last updated: Aug 2, 2025

Divide Players Into Teams of Equal Skill

October 4, 2024 · 6 min · array · breadth-first-search · database · depth-first-search · dynamic-programming · graph · hash-table · leetcode · math · nsum · sorting · two-pointers · union-find · video · Last updated: Aug 2, 2025

Make Sum Divisible by P

October 3, 2024 · 7 min · array · graph · hash-table · leetcode · matrix · prefix · prefix-sum · string · todo · topological-sort · Last updated: Aug 2, 2025

Rank Transform of an Array

October 2, 2024 · 3 min · array · hash-table · hashmap · leetcode · sorting · todo · video · Last updated: Aug 2, 2025

Check If Array Pairs Are Divisible by k

October 1, 2024 · 4 min · array · counting · hash-table · leetcode · todo · video · Last updated: Aug 2, 2025

September ²⁶

Design a Stack With Increment Operation

September 30, 2024 · 3 min · array · design · design/data-structure · java · leetcode · python · stack · todo · Last updated: Aug 2, 2025

Sum of Prefix Scores of Strings

September 25, 2024 · 8 min · array · counting · enumeration · leetcode · math · string · trie · Last updated: Aug 2, 2025

Find the Length of the Longest Common Prefix

September 24, 2024 · 9 min · array · binary-indexed-tree · binary-search · bit-manipulation · counting · database · depth-first-search · dynamic-programming · enumeration · geometry · greedy · hash-function · hash-table · hashing · heap-priority-queue · interactive · leetcode · linked-list · math · matrix · number-theory · ordered-set · prefix-sum · rolling-hash · segment-tree · simulation · sorting · string · string-matching · todo · tree · trie · Last updated: Aug 2, 2025

Extra Characters in a String

September 23, 2024 · 4 min · array · backtracking · binary-indexed-tree · binary-search · bit-manipulation · bitmask · brainteaser · database · dynamic-programming · enumeration · graph · greedy · hash-table · heap-priority-queue · interactive · leetcode · math · matrix · memoization · monotonic-stack · number-theory · ordered-set · prefix-sum · segment-tree · shortest-path · simulation · sliding-window · sorting · stack · string · trie · union-find · Last updated: Aug 2, 2025

Minimum Absolute Difference

September 21, 2024 · 2 min · array · binary-search · combinatorics · leetcode · math · number-theory · sorting · Last updated: Aug 2, 2025

Trough index in a Valley array

September 20, 2024 · 2 min · bitonic · Last updated: Aug 2, 2025

Delete List Nodes With Larger Value Node on the Right

September 17, 2024 · 3 min · Last updated: Aug 2, 2025

Uncommon Words from Two Sentences

September 17, 2024 · 2 min · counting · hash-table · java · leetcode · python · string · todo · video · Last updated: Aug 2, 2025

Flatten a Multi-Level Linked List in Depth-first way

September 15, 2024 · 4 min · linkedlist · Last updated: Aug 2, 2025

Find the Longest Substring Containing Vowels in Even Counts

September 15, 2024 · 7 min · bit-manipulation · bits · hash-table · hashing · leetcode · prefix-sum · string · video · Last updated: Aug 2, 2025

Longest Subarray With Maximum Bitwise AND

September 14, 2024 · 4 min · array · bit-manipulation · bits · brainteaser · dynamic-programming · leetcode · prefix-sum · video · Last updated: Jul 30, 2025

XOR Queries of a Subarray

September 13, 2024 · 4 min · array · bit-manipulation · bits · breadth-first-search · graph · hash-table · leetcode · prefix-sum · sorting · video · Last updated: Aug 2, 2025

Count the Number of Consistent Strings

September 12, 2024 · 5 min · array · bit-manipulation · counting · hash-table · leetcode · string · video · Last updated: Aug 2, 2025

Insert Greatest Common Divisors in Linked List

September 10, 2024 · 4 min · array · dynamic-programming · gcd · greedy · hash-table · leetcode · linked-list · linkedlist · math · number-theory · numerical-algo · simulation · sorting · string · video · Last updated: Aug 2, 2025

Minimum Steps to Traverse Points in an Infinite 2D Grid

September 7, 2024 · 3 min · daily-coding-problem · interviewbit · Last updated: Aug 16, 2025

Conditional selection between x and y with bitwise operations

September 7, 2024 · 3 min · daily-coding-problem · java · python · Last updated: Aug 2, 2025

Alternating Two-Instance Singleton Pattern

September 7, 2024 · 2 min · daily-coding-problem · singleton · design-pattern · Last updated: Jan 7, 2025

Delete Nodes From Linked List Present in Array

September 6, 2024 · 3 min · array · binary-indexed-tree · binary-search · bit-manipulation · brainteaser · breadth-first-search · combinatorics · counting · database · depth-first-search · design · dynamic-programming · enumeration · game-theory · geometry · graph · greedy · hash-table · java · leetcode · linked-list · linkedlist · math · matrix · monotonic-stack · number-theory · ordered-set · prefix-sum · python · simulation · sliding-window · sorting · stack · string · tree · two-pointers · union-find · video · Last updated: Aug 2, 2025

Validating Consistency of Directional Rules Between Points

September 5, 2024 · 5 min · daily-coding-problem · Last updated: Aug 2, 2025

Find Missing Observations

September 5, 2024 · 6 min · array · counting · game-theory · greedy · leetcode · math · maths · simulation · video · Last updated: Aug 2, 2025

Capturing Loop Variables in Lambdas Problem

September 5, 2024 · 3 min · daily-coding-problem · Last updated: Sep 5, 2024

Walking Robot Simulation

September 4, 2024 · 5 min · array · hash-table · leetcode · simulation · video · Last updated: Aug 2, 2025

Read N characters given read7

September 3, 2024 · 3 min · daily-coding-problem · Last updated: Aug 2, 2025

Sum of Digits of String After Convert

September 3, 2024 · 4 min · array · backtracking · binary-search · bit-manipulation · bitmask · database · dynamic-programming · enumeration · geometry · greedy · hash-function · hash-table · leetcode · math · monotonic-stack · number-theory · simulation · stack · string · trie · video · Last updated: Aug 2, 2025

Find the Student that Will Replace the Chalk

September 2, 2024 · 4 min · array · binary-search · counting · dynamic-programming · hash-table · java · leetcode · math · matrix · prefix-sum · python · simulation · stack · string · video · Last updated: Aug 2, 2025

Convert 1D Array Into 2D Array

September 1, 2024 · 4 min · array · leetcode · matrix · simulation · video · Last updated: Aug 2, 2025

August ²⁰

Modify Graph Edge Weights

August 30, 2024 · 6 min · array · binary-search · database · graph · greedy · heap-priority-queue · leetcode · shortest-path · sorting · Last updated: Jul 31, 2025

Minimum Columns to Remove for Lexicographical Order in Matrix

August 16, 2024 · 4 min · daily-coding-problem · greedy · Last updated: Aug 2, 2025

Random Pick with Blacklist

August 16, 2024 · 4 min · array · binary-search · daily-coding-problem · hash-table · leetcode · math · randomized · sorting · Last updated: Aug 2, 2025

Maximum Distance in Arrays

August 16, 2024 · 4 min · array · greedy · leetcode · video · Last updated: Aug 2, 2025

Lemonade Change

August 15, 2024 · 3 min · array · greedy · leetcode · video · Last updated: Aug 2, 2025

Find K-th Smallest Pair Distance

August 14, 2024 · 8 min · array · binary-search · bucketsort · leetcode · search/binary · sorting · todo · two-pointers · Last updated: Aug 2, 2025

Efficient Conversion Between Imperial Distance Units

August 11, 2024 · 3 min · daily-coding-problem · design/data-structure · Last updated: Aug 2, 2025

Regions Cut By Slashes

August 10, 2024 · 5 min · array · breadth-first-search · depth-first-search · hash-table · leetcode · matrix · union-find · Last updated: Aug 2, 2025

Magic Squares In Grid

August 9, 2024 · 7 min · array · hash-table · leetcode · math · matrix · numerical-algo · video · Last updated: Aug 2, 2025

Spiral Matrix 4 - From Linked List

August 9, 2024 · 3 min · array · dynamic-programming · leetcode · linked-list · matrix · queue · simulation · video · Last updated: Aug 2, 2025

Spiral Matrix 3 - Traverse from Given Starting Point

August 8, 2024 · 4 min · array · leetcode · matrix · simulation · video · Last updated: Aug 2, 2025

Minimum Number of Pushes to Type Word 2

August 6, 2024 · 7 min · array · bit-manipulation · counting · dynamic-programming · enumeration · frequency · geometry · graph · greedy · hash-function · hash-table · leetcode · math · matrix · memoization · prefix-sum · rolling-hash · simulation · sliding-window · sorting · string · string-matching · trie · video · Last updated: Aug 2, 2025

Kth Distinct String in an Array

August 5, 2024 · 4 min · array · counting · hash-table · hashing · leetcode · string · video · Last updated: Aug 2, 2025

Determining the Existence of a Valid Secret Code in Mastermind Based on Given Guesses and Scores Guesses and Scores

August 5, 2024 · 4 min · daily-coding-problem · backtracking · Last updated: Aug 2, 2025

Range Sum of Sorted Subarray Sums

August 4, 2024 · 8 min · array · binary-search · leetcode · sorting · two-pointers · video · Last updated: Aug 2, 2025

Minimum jumps to reduce number to 1

August 4, 2024 · 4 min · daily-coding-problem · graph · Last updated: Jun 13, 2025

Make Two Arrays Equal by Reversing Subarrays

August 3, 2024 · 2 min · array · hash-table · hashing · leetcode · sorting · Last updated: Aug 2, 2025

Minimum Swaps to Group All 1’s Together 1 - In an array

August 2, 2024 · 3 min · array · hash-table · leetcode · sliding-window · sorting · string · Last updated: Aug 2, 2025

Minimum Swaps to Group All 1’s Together 2 - In circular array

August 2, 2024 · 5 min · array · bit-manipulation · hash-table · leetcode · sliding-window · sorting · string · Last updated: Aug 2, 2025

Number of Senior Citizens

August 1, 2024 · 2 min · array · bit-manipulation · dynamic-programming · greedy · hash-table · heap-priority-queue · leetcode · math · matrix · prefix-sum · simulation · sorting · string · video · Last updated: Aug 2, 2025

July ³⁸

Largest value path in a directed graph

July 31, 2024 · 4 min · graph · cycle · dfs · daily-coding-problem · Last updated: Aug 2, 2025

Filling Bookcase Shelves

July 31, 2024 · 5 min · array · dynamic-programming · leetcode · video · Last updated: Aug 2, 2025

Implement rand5() using rand7()

July 31, 2024 · 2 min · daily-coding-problem · rejection-sampling · Last updated: Aug 2, 2025

Bishop diagonally attack on chess board

July 31, 2024 · 4 min · leetcode · daily-coding-problem · hashing · hashmap · Last updated: Aug 2, 2025

Minimum Deletions to Make String Balanced

July 30, 2024 · 6 min · array · breadth-first-search · dynamic-programming · leetcode · stack · string · video · Last updated: Aug 2, 2025

Count Number of Teams

July 29, 2024 · 6 min · array · binary-indexed-tree · counting · dynamic-programming · leetcode · segment-tree · video · Last updated: Aug 2, 2025

Second Minimum Time to Reach Destination

July 28, 2024 · 6 min · array · backtracking · binary-tree · breadth-first-search · depth-first-search · dijkstra · enumeration · graph · leetcode · linked-list · math · shortest-path · sorting · string · tree · two-pointers · Last updated: Jul 31, 2025

Shortest Uphill-Downhill Route for a Competitive Runner

July 27, 2024 · 5 min · daily-coding-problem · dfs · leetcode · Last updated: Aug 2, 2025

Minimum Cost to Convert String 1

July 27, 2024 · 5 min · array · backtracking · binary-search · bit-manipulation · bitmask · breadth-first-search · counting · database · dynamic-programming · floyd-warshall · graph · hash-table · leetcode · math · memoization · number-theory · prefix-sum · shortest-path · sliding-window · sorting · string · trie · video · Last updated: Jul 31, 2025

Count Knight’s Tour

July 26, 2024 · 2 min · daily-coding-problem · Last updated: Aug 2, 2025

Sort the Jumbled Numbers

July 24, 2024 · 3 min · array · hashmap · leetcode · sorting · video · Last updated: Aug 2, 2025

Simulating an Unbiased Coin Toss Using a Biased Coin

July 23, 2024 · 3 min · daily-coding-problem · leetcode · maths · probability · random · Last updated: Aug 2, 2025

Sort Array by Increasing Frequency

July 23, 2024 · 3 min · array · dynamic-programming · enumeration · frequency · hash-table · java · leetcode · python · sorting · string · video · Last updated: Aug 2, 2025

Interleave the first half of the stack with second half using one queue

July 22, 2024 · 3 min · leetcode · stack · queue · Last updated: Aug 2, 2025

Sort the People

July 22, 2024 · 3 min · array · hash-table · java · leetcode · python · sorting · string · video · Last updated: Aug 2, 2025

Build a Matrix With Conditions

July 21, 2024 · 8 min · array · backtracking · binary-search · bit-manipulation · bitmask · brainteaser · combinatorics · counting · database · dynamic-programming · enumeration · graph · greedy · hash-table · heap-priority-queue · leetcode · math · matrix · monotonic-queue · prefix-sum · queue · simulation · sliding-window · sorting · string · topological-sort · two-pointers · Last updated: Aug 2, 2025

Find Valid Matrix Given Row and Column Sums

July 20, 2024 · 3 min · array · database · greedy · heap-priority-queue · leetcode · matrix · ordered-set · video · Last updated: Aug 2, 2025

Lucky Numbers in a Matrix

July 19, 2024 · 4 min · array · leetcode · matrix · video · Last updated: Aug 2, 2025

Delete Nodes And Return Forest

July 17, 2024 · 2 min · array · binary-tree · concurrency · counting · database · depth-first-search · dfs · hash-table · leetcode · math · stack · string · traversal/postorder · tree · video · Last updated: Aug 2, 2025

Step-By-Step Directions From a Binary Tree Node to Another

July 16, 2024 · 4 min · array · binary-tree · bt-binary-tree · depth-first-search · dynamic-programming · eulerian-circuit · graph · greedy · hash-table · heap-priority-queue · leetcode · prefix-sum · sorting · string · tree · Last updated: Aug 2, 2025

Create Binary Tree From Descriptions

July 15, 2024 · 3 min · array · binary-tree · bt-binary-tree · database · hash-table · leetcode · math · number-theory · stack · tree · video · Last updated: Aug 2, 2025

Number of Atoms

July 14, 2024 · 6 min · hash-table · leetcode · sorting · stack · string · Last updated: Aug 2, 2025

Low bandwidth almost similar file syncing algorithm between two computers

July 13, 2024 · 5 min · daily-coding-problem · Last updated: Jan 4, 2025

m Coloring Problem - undirected graph as adjacency matrix

July 13, 2024 · 3 min · daily-coding-problem · backtracking · dfs · Last updated: Aug 2, 2025

Locking and unlocking resources represented as binary tree nodes

July 13, 2024 · 3 min · daily-coding-problem · bt-binary-tree · mutual-exclusion · locking · traversal/preorder · Last updated: Aug 2, 2025

Find the Shortest Path between 2 cells in boolean maze

July 13, 2024 · 6 min · bfs · daily-coding-problem · shortest-path · Last updated: Aug 2, 2025

Design log Order records

July 13, 2024 · 3 min · daily-coding-problem · array/circular · Last updated: Aug 2, 2025

Maximum Score From Removing Substrings

July 12, 2024 · 3 min · array · backtracking · bit-manipulation · graph · greedy · leetcode · stack · string · tree · Last updated: Aug 2, 2025

Reverse Substrings Between Each Pair of Parentheses

July 11, 2024 · 4 min · leetcode · stack · string · Last updated: Aug 2, 2025

Estimating the value of Pi using Monte Carlo method

July 10, 2024 · 3 min · daily-coding-problem · named-algo-ds/algo · monte-carlo · Last updated: Jul 31, 2025

Implement Job Scheduler with Delay Function Execution

July 10, 2024 · 1 min · programming-language · daily-coding-problem · schedule · queue/priority · Last updated: Jan 4, 2025

Implementing car and cdr Functions for Pair Construction

July 9, 2024 · 1 min · daily-coding-problem · Last updated: Jan 4, 2025

Find the Winner of the Circular Game

July 8, 2024 · 7 min · array · data-stream · design · dynamic-programming · geometry · greedy · heap-priority-queue · leetcode · math · numerical-algo · ordered-set · queue · recursion · simulation · two-pointers · video · Last updated: Jul 31, 2025

Water Bottles

July 8, 2024 · 3 min · leetcode · math · maths · numerical-algo · simulation · Last updated: Jul 31, 2025

Find the Minimum and Maximum Number of Nodes Between Critical Points

July 5, 2024 · 5 min · array · breadth-first-search · combinatorics · dynamic-programming · hash-table · leetcode · linked-list · linkedlist · math · matrix · simulation · string · video · Last updated: Aug 2, 2025

Merge Nodes in Between Zeros

July 4, 2024 · 5 min · array · bit-manipulation · bitmask · counting · dynamic-programming · greedy · hash-table · heap-priority-queue · leetcode · linked-list · linkedlist · math · number-theory · simulation · string · string-matching · video · Last updated: Aug 2, 2025

Minimum Difference Between Largest and Smallest Value in Three Moves

July 3, 2024 · 6 min · array · greedy · leetcode · sorting · video · Last updated: Aug 2, 2025

Three Consecutive Odds

July 1, 2024 · 1 min · array · leetcode · math · video · Last updated: Aug 2, 2025

June ³¹

Find All Groups of Farmland

June 30, 2024 · 7 min · array · breadth-first-search · depth-first-search · disjoint-set · leetcode · matrix · todo · union-find · Last updated: Jul 30, 2025

Accounts Merge

June 30, 2024 · 4 min · array · breadth-first-search · depth-first-search · disjoint-set · hash-table · leetcode · sorting · string · todo · union-find · Last updated: Aug 2, 2025

All Ancestors of a Node in a Directed Acyclic Graph

June 29, 2024 · 9 min · array · bfs · binary-indexed-tree · breadth-first-search · depth-first-search · dfs · graph · graph-degree · graph/dag · greedy · kahn-algorithm · leetcode · math · sorting · string · topological-sort · two-pointers · video · Last updated: Aug 2, 2025

Split Linked List in Parts

June 29, 2024 · 4 min · leetcode · linked-list · linkedlist · todo · video · Last updated: Aug 2, 2025

Maximum Total Importance of Roads

June 28, 2024 · 4 min · array · binary-indexed-tree · binary-search · breadth-first-search · counting · database · design · doubly-linked-list · dynamic-programming · graph · greedy · hash-table · heap-priority-queue · leetcode · linked-list · matrix · monotonic-stack · segment-tree · shortest-path · simulation · sorting · stack · string · video · Last updated: Aug 2, 2025

Find the length of the linked list

June 28, 2024 · 1 min · linkedlist · Last updated: Aug 2, 2025

Remove duplicates from an unsorted linked list keeping only unique elements

June 28, 2024 · 2 min · hash-table · leetcode · linked-list · math · Last updated: Aug 2, 2025

Find Center of Star Graph

June 27, 2024 · 3 min · array · graph · graph/star · greedy · heap-priority-queue · leetcode · video · Last updated: Aug 2, 2025

Balance a Binary Search Tree

June 26, 2024 · 2 min · binary-search-tree · binary-tree · bst-binary-search-tree · depth-first-search · divide-and-conquer · greedy · leetcode · tree · video · Last updated: Aug 2, 2025

Longest Continuous Subarray With Absolute Diff Less Than or Equal to Limit Problem

June 23, 2024 · 6 min · array · binary-search · database · heap-priority-queue · leetcode · matrix · monotonic-queue · ordered-set · queue · queue/deque · simulation · sliding-window · stack · Last updated: Aug 2, 2025

Count Number of Nice Subarrays

June 22, 2024 · 4 min · array · hash-table · leetcode · math · prefix-sum · sliding-window · Last updated: Aug 2, 2025

Grumpy Bookstore Owner

June 21, 2024 · 3 min · array · counting · greedy · hash-table · heap-priority-queue · leetcode · sliding-window · sorting · Last updated: Aug 2, 2025

Magnetic Force Between Two Balls

June 20, 2024 · 4 min · array · binary-search · leetcode · search/binary · sorting · Last updated: Aug 2, 2025

Most Profit Assigning Work

June 18, 2024 · 5 min · array · binary-search · greedy · leetcode · search/binary · sorting · two-pointers · video · Last updated: Aug 2, 2025

Number of cells in multiplication table containing X

June 18, 2024 · 5 min · leetcode · daily-coding-problem · numerical-algo · modulo-operator · division · Last updated: Jul 31, 2025

Nth Number with sum of digits as 10

June 18, 2024 · 2 min · daily-coding-problem · numerical-algo · Last updated: Jul 31, 2025

Sum of Square Numbers

June 17, 2024 · 2 min · binary-search · hashing · leetcode · math · numerical-algo · two-pointers · video · Last updated: Jul 31, 2025

IPO

June 15, 2024 · 5 min · array · greedy · heap-priority-queue · leetcode · queue/priority · sorting · video · Last updated: Aug 2, 2025

Minimum Number of Moves to Seat Everyone

June 13, 2024 · 3 min · array · counting-sort · greedy · leetcode · sorting · video · Last updated: Aug 16, 2025

Relative Sort Array

June 11, 2024 · 3 min · array · binary-tree · breadth-first-search · bucketsort · counting-sort · depth-first-search · hash-table · leetcode · monotonic-stack · prefix-sum · sorting · stack · tree · video · Last updated: Aug 2, 2025

Max Stack

June 11, 2024 · 5 min · daily-coding-problem · design · doubly-linked-list · leetcode · linked-list · ordered-set · stack · Last updated: Aug 2, 2025

Height Checker

June 10, 2024 · 4 min · array · bucketsort · counting-sort · leetcode · sorting · video · Last updated: Aug 2, 2025

Replace Words

June 7, 2024 · 2 min · array · hash-table · leetcode · string · trie · Last updated: Aug 2, 2025

Buildings with sunset view

June 7, 2024 · 4 min · daily-coding-problem · queue/monotonic · stack/monotonic · Last updated: Aug 2, 2025

Find Common Characters

June 5, 2024 · 2 min · array · binary-search · greedy · hash-table · leetcode · map · math · minimum · prefix-sum · simulation · sliding-window · sorting · stack · string · video · Last updated: Aug 2, 2025

Level of Binary Tree with minimum sum

June 5, 2024 · 2 min · bfs · binary-tree · breadth-first-search · daily-coding-problem · depth-first-search · leetcode · traversal/level-order · tree · Last updated: Aug 2, 2025

RLE Iterator

June 4, 2024 · 5 min · array · counting · design · iterator · leetcode · Last updated: Aug 2, 2025

Decompress Run-Length Encoded List

June 4, 2024 · 2 min · array · leetcode · Last updated: Aug 2, 2025

Append Characters to String to Make Subsequence

June 3, 2024 · 2 min · greedy · leetcode · string · subsequence · two-pointers · Last updated: Aug 2, 2025

Score of a String

June 2, 2024 · 2 min · array · binary-search · bit-manipulation · breadth-first-search · combinatorics · counting · database · depth-first-search · dynamic-programming · enumeration · graph · greedy · hash-table · heap-priority-queue · leetcode · math · matrix · monotonic-stack · number-theory · prefix-sum · queue · segment-tree · shortest-path · sorting · stack · string · two-pointers · video · Last updated: Aug 2, 2025

Search in Rotated Sorted Array - Duplicates Allowed

June 1, 2024 · 2 min · Last updated: Aug 2, 2025

May ²⁶

Number of Overlapping Lines between points on 2 parallel lines

May 30, 2024 · 1 min · coordinate-geometry · daily-coding-problem · leetcode · sorting · Last updated: Jul 31, 2025

Count Triplets That Can Form Two Arrays of Equal XOR

May 30, 2024 · 3 min · array · bit-manipulation · bits · hash-table · leetcode · math · prefix-sum · Last updated: Aug 2, 2025

Reverse words in a string keep delimiters in order

May 30, 2024 · 2 min · leetcode · stack · queue · reverse · string · Last updated: Aug 2, 2025

Number of Steps to Reduce a Number in Binary Representation to One

May 29, 2024 · 4 min · bit-manipulation · leetcode · string · video · Last updated: Aug 2, 2025

Maximum Sum Subarray of Size K

May 29, 2024 · 2 min · Last updated: Aug 2, 2025

Get Equal Substrings Within Budget

May 28, 2024 · 2 min · binary-search · leetcode · prefix-sum · sliding-window · string · video · Last updated: Aug 2, 2025

Special Array With X Elements Greater Than or Equal X

May 27, 2024 · 6 min · array · binary-search · binary-tree · breadth-first-search · geometry · leetcode · math · sliding-window · sorting · tree · video · Last updated: Aug 2, 2025

Maximum Score Words Formed by Letters

May 24, 2024 · 4 min · array · backtracking · bit-manipulation · bitmask · breadth-first-search · depth-first-search · dynamic-programming · hash-table · leetcode · math · string · tree · union-find · video · Last updated: Aug 2, 2025

The Number of Beautiful Subsets

May 23, 2024 · 3 min · array · backtracking · combinatorics · dynamic-programming · greedy · hash-table · heap-priority-queue · leetcode · math · sorting · video · Last updated: Aug 2, 2025

Sum of All Subset XOR Totals

May 20, 2024 · 3 min · array · backtracking · bit-manipulation · combinatorics · design · enumeration · greedy · hash-table · leetcode · math · string · video · xor · Last updated: Aug 2, 2025

Distribute Coins in Binary Tree

May 18, 2024 · 3 min · binary-tree · bt-binary-tree · depth-first-search · dfs · leetcode · traversal/postorder · tree · video · Last updated: Aug 2, 2025

Delete Leaves With a Given Value

May 17, 2024 · 3 min · binary-tree · bt-binary-tree · depth-first-search · dfs · leetcode · traversal/postorder · tree · video · Last updated: Aug 2, 2025

Evaluate Boolean Binary Tree

May 16, 2024 · 2 min · array · binary-search · binary-tree · bt-binary-tree · combinatorics · counting · database · depth-first-search · design · divide-and-conquer · dynamic-programming · greedy · hash-table · heap-priority-queue · leetcode · math · monotonic-stack · number-theory · ordered-set · quickselect · radix-sort · sorting · stack · string · tree · two-pointers · union-find · video · Last updated: Aug 2, 2025

Find the Safest Path in a Grid

May 15, 2024 · 6 min · array · bfs · binary-search · breadth-first-search · dijkstra · greedy · hash-table · heap-priority-queue · leetcode · matrix · matrix/binary · shortest-path · sorting · stack · union-find · video · Last updated: Aug 2, 2025

Path with Maximum Gold

May 14, 2024 · 5 min · array · backtracking · bfs · dfs · leetcode · matrix · video · Last updated: Aug 2, 2025

Score After Flipping Matrix

May 13, 2024 · 4 min · array · binary-matrix · bit-manipulation · bits · greedy · leetcode · matrix · video · Last updated: Aug 2, 2025

Largest Local Values in a Matrix

May 12, 2024 · 3 min · array · leetcode · matrix · sliding-window · video · Last updated: Aug 2, 2025

Print binary search tree in increasing order

May 12, 2024 · 1 min · leetcode · bst-binary-search-tree · Last updated: Aug 2, 2025

Minimum Cost to Hire K Workers

May 11, 2024 · 5 min · array · greedy · heap-priority-queue · heap/max · leetcode · queue/priority · sorting · video · Last updated: Aug 2, 2025

K-th Smallest Prime Fraction

May 10, 2024 · 4 min · array · binary-search · greedy · heap-priority-queue · heap/min · k-smallest-largest · kth · leetcode · queue/priority · smallest · sorting · two-pointers · video · Last updated: Aug 2, 2025

Maximize Happiness of Selected Children

May 9, 2024 · 5 min · array · bit-manipulation · counting · counting-sort · database · dynamic-programming · enumeration · greedy · hash-table · heap-priority-queue · heap/max · interactive · leetcode · math · matrix · ordered-set · prefix-sum · priority-queue · simulation · sliding-window · sorting · string · trie · video · Last updated: Aug 2, 2025

Relative Ranks

May 8, 2024 · 3 min · array · heap-priority-queue · heap/max · leetcode · priority-queue · sorting · video · Last updated: Aug 2, 2025

Double a Number Represented as a Linked List

May 7, 2024 · 4 min · arithmetic · array · binary-search · bit-manipulation · combinatorics · counting · database · dynamic-programming · enumeration · graph · greedy · hash-table · leetcode · linked-list · linkedlist · math · monotonic-stack · number-theory · ordered-set · prefix-sum · sliding-window · sorting · stack · string · strongly-connected-component · tree · two-pointers · Last updated: Aug 2, 2025

Remove nodes in linked list with greater value on right side

May 6, 2024 · 3 min · array · hash-table · leetcode · linked-list · linkedlist · math · monotonic-stack · prefix-sum · recursion · stack · string · Last updated: Aug 2, 2025

Largest Positive Integer That Exists With Its Negative

May 3, 2024 · 2 min · array · array-algo · counting · enumeration · hash-table · leetcode · math · nsum · sorting · string · two-pointers · video · Last updated: Aug 2, 2025

Reverse Prefix of Word

May 2, 2024 · 2 min · array · array-algo · hash-table · leetcode · stack · string · two-pointers · video · Last updated: Aug 2, 2025

April ¹

Given a binary search tree with 2 nodes swapped find number of pairs not following BST properties

April 24, 2024 · 1 min · bst-binary-search-tree · traversal/inorder · Last updated: Aug 2, 2025

February ¹¹

Meeting Rooms 3

February 18, 2024 · 6 min · array · hash-table · heap-priority-queue · leetcode · simulation · sorting · Last updated: Aug 1, 2025

Permutations of Array 2 - Array has duplicates

February 16, 2024 · 2 min · array · backtracking · duplicates-algo · leetcode · todo · Last updated: Aug 2, 2025

Combination Sum 4 - All permutations

February 16, 2024 · 3 min · array · dynamic-programming · leetcode · permutation-combination · Last updated: Aug 2, 2025

Understanding Deck of Cards

February 12, 2024 · 1 min · Last updated: Aug 2, 2024

Implement multiplication, subtraction, and division using only addition

February 10, 2024 · 4 min · ctci · puzzle · bits · maths · multiplication · divisor · add · Last updated: Nov 16, 2024

Continuous Subarray Sum

February 10, 2024 · 5 min · array · hash-table · hashing · leetcode · math · maths · modulo-operator · prefix-sum · video · Last updated: Aug 2, 2025

Implement Power Function 1

February 10, 2024 · 2 min · bits · daily-coding-problem · divide-n-conquer · leetcode · math · maths · recursion · search/binary · Last updated: Jul 31, 2025

Maximum Points on a Line

February 10, 2024 · 7 min · array · coordinate-geometry · duplicates-algo · geometry · hash-table · leetcode · math · maths · max-min · Last updated: Aug 2, 2025

Missing Number

February 10, 2024 · 9 min · array · binary-search · bit-manipulation · bits · hash-table · leetcode · math · maths · missing · sorting · video · Last updated: Aug 2, 2025

Reverse Integer

February 10, 2024 · 3 min · integer · interviewbit · leetcode · math · maths · reverse · todo · Last updated: Jul 31, 2025

Palindrome Number

February 10, 2024 · 3 min · interviewbit · leetcode · math · maths · palindrome · video · Last updated: Aug 2, 2025

January ¹⁴¹

Additive Number

January 27, 2024 · 3 min · backtracking · leetcode · string · todo · Last updated: Aug 2, 2025

Check If a String Can Break Another String

January 27, 2024 · 2 min · greedy · leetcode · sorting · string · todo · Last updated: Aug 2, 2025

Check if One String Swap Can Make Strings Equal

January 27, 2024 · 3 min · counting · hash-table · leetcode · string · video · Last updated: Aug 2, 2025

Custom Sort String

January 27, 2024 · 3 min · hash-table · leetcode · sorting · string · todo · Last updated: Aug 2, 2025

Delete and Earn

January 27, 2024 · 3 min · array · dynamic-programming · hash-table · leetcode · todo · Last updated: Aug 2, 2025

Determine if Two Strings Are Close

January 27, 2024 · 3 min · counting · hash-table · leetcode · sorting · string · todo · Last updated: Aug 2, 2025

Edit Distance - Insert, Delete, no replace

January 27, 2024 · 4 min · todo · string · string-algo · edit-distance · Last updated: Aug 2, 2025

Find Longest Awesome Substring

January 27, 2024 · 3 min · bit-manipulation · database · hash-table · leetcode · string · todo · Last updated: Aug 2, 2025

Friend Words - One Edit Distance

January 27, 2024 · 4 min · edit-distance · friendship · leetcode · string · todo · two-pointers · Last updated: Aug 2, 2025

Largest Odd Number in String

January 27, 2024 · 2 min · greedy · leetcode · math · string · todo · Last updated: Aug 2, 2025

Largest Substring Between Two Equal Characters

January 27, 2024 · 2 min · breadth-first-search · depth-first-search · enumeration · hash-table · leetcode · string · todo · Last updated: Aug 2, 2025

Longest Common Subsequence of Three Sequences

January 27, 2024 · 3 min · todo · string-algo · dynamic-programming · longest · Last updated: Aug 2, 2025

Longest Duplicate Substring Problem

January 27, 2024 · 10 min · binary-search · database · hash-function · hashing/rolling · leetcode · rolling-hash · sliding-window · string · suffix-array · suffix-tree · todo · Last updated: Nov 9, 2024

Longest Happy Prefix

January 27, 2024 · 2 min · hash-function · leetcode · rolling-hash · string · string-matching · todo · Last updated: Aug 2, 2025

Minimum Number of Removals to Make Mountain Array

January 27, 2024 · 4 min · array · binary-search · dynamic-programming · greedy · leetcode · lis-longest-increasing-subsequence · todo · Last updated: Aug 2, 2025

Search a long string for small strings in an array

January 27, 2024 · 5 min · ctci · todo · search · suffix · suffix-tree · pattern-matching · Last updated: Aug 2, 2025

Shortest Common Supersequence

January 27, 2024 · 5 min · array · dynamic-programming · leetcode · math · np-complete · probability-and-statistics · sequence · string · string-algo · todo · Last updated: Aug 2, 2025

Split Message Based on Limit Problem

January 27, 2024 · 5 min · array · binary-search · binary-search-tree · binary-tree · breadth-first-search · daily-coding-problem · database · depth-first-search · dynamic-programming · graph · greedy · hash-table · heap-priority-queue · leetcode · math · number-theory · shortest-path · sorting · string · todo · tree · two-pointers · word · word-break · Last updated: Nov 14, 2024

Z Algorithm String Searching

January 27, 2024 · 5 min · todo · string · string-algo · pattern-matching · Last updated: Aug 2, 2025

Balanced Binary Tree

January 26, 2024 · 4 min · balanced-bst · binary-tree · bt-binary-tree · ctci · depth-first-search · leetcode · tree · Last updated: Aug 6, 2025

Best Team With No Conflicts

January 26, 2024 · 5 min · array · binary-tree · design · dynamic-programming · hash-table · leetcode · math · number-theory · sorting · stack · string · todo · tree · union-find · Last updated: Aug 2, 2025

Best Time To Buy And Sell Stock With Cooldown

January 26, 2024 · 3 min · array · dynamic-programming · interviewbit · leetcode · state-machine · stock-algo · Last updated: Aug 2, 2025

Binary Tree Path Sum - Maximum between any two nodes

January 26, 2024 · 5 min · binary-tree · binary-tree-path · bt-binary-tree · depth-first-search · dynamic-programming · leetcode · path-finding · pathsum · todo · tree · Last updated: Aug 2, 2025

Binary Tree Traversal - Zigzag Level Order Traversal

January 26, 2024 · 6 min · bfs · binary-tree · breadth-first-search · bt-binary-tree · leetcode · traversal · traversal/level-order · tree · zigzag · Last updated: Aug 8, 2025

Binary Tree Upside Down

January 26, 2024 · 3 min · binary-tree · depth-first-search · leetcode · todo · tree · Last updated: Aug 2, 2025

Boyer-Moore String Searching

January 26, 2024 · 11 min · todo · string · string-algo · pattern-matching · substring · named-algo-ds · Last updated: Aug 2, 2025

Buddy Strings

January 26, 2024 · 5 min · hash-table · leetcode · string · todo · Last updated: Aug 2, 2025

Calculate the Binomial Coefficient

January 26, 2024 · 5 min · todo · dynamic-programming · numerical-algo · Last updated: Aug 2, 2025

Calculating the mean and median of an unsorted array

January 26, 2024 · 3 min · todo · median · statistics · array · Last updated: Aug 2, 2025

Check if Move is Legal

January 26, 2024 · 4 min · array · dynamic-programming · enumeration · hash-function · leetcode · matrix · rolling-hash · string · todo · two-pointers · Last updated: Aug 2, 2025

Check if Word Equals Summation of Two Words

January 26, 2024 · 3 min · greedy · leetcode · string · todo · Last updated: Aug 2, 2025

Cherry Pickup

January 26, 2024 · 15 min · array · dynamic-programming · leetcode · matrix · todo · yna · Last updated: Aug 2, 2025

Cherry Pickup II

January 26, 2024 · 13 min · array · dynamic-programming · leetcode · matrix · Last updated: Aug 2, 2025

Combinations Problem

January 26, 2024 · 4 min · backtracking · leetcode · todo · Last updated: Aug 2, 2025

Construct Binary Tree from Inorder and Postorder Traversal

January 26, 2024 · 3 min · array · binary-tree · bt-binary-tree · divide-and-conquer · hash-table · interviewbit · leetcode · todo · traversal · traversal/inorder · traversal/postorder · tree · Last updated: May 31, 2024

Construct Binary Tree from Inorder and Preorder Traversal

January 26, 2024 · 3 min · array · binary-tree · bt-binary-tree · daily-coding-problem · divide-and-conquer · hash-table · leetcode · todo · traversal/inorder · traversal/preorder · tree · Last updated: Mar 16, 2025

Contains Duplicate 2 - within k distance

January 26, 2024 · 2 min · array · duplicates-algo · hash-table · hashing · leetcode · sliding-window · todo · Last updated: Aug 2, 2025

Contains Duplicate 3 - within k distance and t difference

January 26, 2024 · 3 min · array · bucket-sort · duplicates-algo · leetcode · ordered-set · sliding-window · sorting · todo · Last updated: Aug 2, 2025

Convert Sorted List into a height-balanced Binary search Tree

January 26, 2024 · 5 min · balanced-bst · binary-search-tree · binary-tree · convert · divide-and-conquer · leetcode · linked-list · todo · tree · tree-ds · Last updated: Aug 2, 2025

Count Inversions - Count Smaller on Right

January 26, 2024 · 7 min · todo · array · inversion · daily-coding-problem · count · Last updated: Aug 2, 2025

Count of Smaller Numbers After Self

January 26, 2024 · 20 min · array · array-algo · binary-indexed-tree · binary-search · count · daily-coding-problem · divide-and-conquer · inversion · leetcode · merge-sort · ordered-set · segment-tree · Last updated: Aug 2, 2025

Count Primes

January 26, 2024 · 3 min · array · count · enumeration · leetcode · math · number-theory · todo · Last updated: Aug 6, 2025

Create Maximum Number

January 26, 2024 · 6 min · array · greedy · leetcode · monotonic-stack · stack · stack/monotonic · todo · two-pointers · Last updated: Aug 2, 2025

Depth First Search

January 26, 2024 · 4 min · todo · graph · traversal · video · Last updated: Aug 2, 2025

Different Ways to Add Parentheses

January 26, 2024 · 7 min · dynamic-programming · leetcode · math · memoization · parentheses · recursion · string · todo · Last updated: Aug 2, 2025

Distinct Subsequences

January 26, 2024 · 8 min · dynamic-programming · leetcode · string · todo · Last updated: Aug 2, 2025

Divisor Game

January 26, 2024 · 2 min · brainteaser · dynamic-programming · game-theory · leetcode · math · todo · Last updated: Aug 2, 2025

Dot Product of 2 Sparse Vectors

January 26, 2024 · 5 min · sparse · vector · matrix · array · maths · Last updated: Aug 2, 2025

Euler Graphs - Origin of Graph Theory - Seven bridges of Konigsberg

January 26, 2024 · 4 min · graph · Last updated: Aug 2, 2025

Factor Combinations

January 26, 2024 · 4 min · backtracking · leetcode · Last updated: Jul 31, 2025

Find first position of target element in sorted array

January 26, 2024 · 2 min · divide-n-conquer · search · sorted-array · search/binary · Last updated: Aug 2, 2025

Find Leader Elements in an Array

January 26, 2024 · 3 min · todo · array · integer · Last updated: Aug 2, 2025

Find Median from Data Stream

January 26, 2024 · 5 min · ctci · daily-coding-problem · data-stream · design · heap · heap-priority-queue · leetcode · median · sorting · streaming · todo · two-pointers · Last updated: Aug 2, 2025

Find Peak Element in a Given Array

January 26, 2024 · 3 min · array · array-algo · binary-search · leetcode · Last updated: Aug 2, 2025

Find the Closest Palindrome

January 26, 2024 · 4 min · leetcode · math · string · Last updated: Aug 2, 2025

Find two repeating elements in a given ranged array

January 26, 2024 · 10 min · repeat · todo · duplicates-algo · array-algo · array-1-n · ranged-array · Last updated: Aug 2, 2025

Finding N-th Smallest Sum from Two Sorted Arrays

January 26, 2024 · 4 min · array-algo · two-array · Last updated: Aug 2, 2025

First Unique Character in a Stream of Characters

January 26, 2024 · 7 min · streaming · todo · algorithm · python · misc · array-algo · stream · interviewbit · Last updated: Aug 2, 2025

Fisher-Yates Shuffle

January 26, 2024 · 5 min · array · array-algo · ctci · daily-coding-problem · numerical-algo · probability · random · shuffle · Last updated: Aug 2, 2025

Flip Game 1

January 26, 2024 · 2 min · duplicates-algo · game-development · leetcode · string · todo · Last updated: Aug 2, 2025

Flip Game 2

January 26, 2024 · 3 min · backtracking · dynamic-programming · game-development · game-theory · leetcode · math · memoization · todo · Last updated: Aug 2, 2025

Fraction to Recurring Decimal

January 26, 2024 · 5 min · hash-table · leetcode · math · string · todo · Last updated: Aug 1, 2025

Generate Nth Fibonacci Number

January 26, 2024 · 10 min · ctci · dynamic-programming · fibonacci · leetcode · math · memoization · recursion · todo · video · Last updated: Jul 31, 2025

Gray Code

January 26, 2024 · 3 min · backtracking · bit-manipulation · bits · leetcode · math · Last updated: Aug 2, 2025

Implement rand7() using rand5()

January 26, 2024 · 6 min · ctci · probability · random · daily-coding-problem · Last updated: Aug 2, 2025

Jump Game 2 - Get min jumps

January 26, 2024 · 7 min · array · dynamic-programming · game-development · greedy · leetcode · todo · Last updated: Aug 6, 2025

Knight Dialer

January 26, 2024 · 7 min · dynamic-programming · leetcode · todo · Last updated: Aug 2, 2025

Knight’s Tour

January 26, 2024 · 5 min · backtracking · path-finding · Last updated: Aug 2, 2025

Knuth Morris Pratt KMP Algorithm

January 26, 2024 · 9 min · todo · string · string-algo · pattern-matching · substring · named-algo-ds/algo · Last updated: Aug 2, 2025

kSum

January 26, 2024 · 2 min · backtracking · nsum · Last updated: Aug 2, 2025

Kth Permutation Sequence of Numbers 1 to N

January 26, 2024 · 9 min · kth · leetcode · math · permutation-combination · recursion · todo · Last updated: Aug 2, 2025

Largest Rectangle in Histogram

January 26, 2024 · 13 min · array · dynamic-programming · leetcode · max-min · monotonic-stack · rectangle · stack · stack/monotonic · todo · Last updated: Aug 2, 2025

Least Number of Perfect Squares that Sums to n

January 26, 2024 · 7 min · bfs · breadth-first-search · daily-coding-problem · dynamic-programming · lagrange · leetcode · math · numerical-algo · square · Last updated: Aug 10, 2025

Linked List in Binary Tree

January 26, 2024 · 3 min · binary-tree · depth-first-search · leetcode · linked-list · linkedlist · todo · tree · video · Last updated: Aug 2, 2025

Longest arithmetic progression in a sorted array

January 26, 2024 · 3 min · dynamic-programming · longest · arithmetic-progression · Last updated: Aug 2, 2025

Longest Palindrome

January 26, 2024 · 2 min · greedy · hash-table · leetcode · palindrome · string · video · Last updated: Aug 2, 2025

Max Chunks To Make Sorted 2

January 26, 2024 · 2 min · array · greedy · leetcode · monotonic-stack · sorting · stack · stack/monotonic · todo · Last updated: Aug 2, 2025

Maximum consecutive repeating character in string

January 26, 2024 · 3 min · todo · string · Last updated: Aug 2, 2025

Maximum Gap

January 26, 2024 · 6 min · array · array-algo · bucket-sort · bucketsort · leetcode · pigeonhole-principle · radix-sort · sorting · Last updated: Aug 2, 2025

Maximum Nesting Depth of the Parentheses

January 26, 2024 · 3 min · leetcode · parentheses · stack · string · todo · Last updated: Aug 2, 2025

Maximum Number of Events That Can Be Attended

January 26, 2024 · 9 min · array · greedy · heap-priority-queue · leetcode · sorting · Last updated: Jul 7, 2025

Maximum Number of Occurrences of a Substring

January 26, 2024 · 2 min · array · breadth-first-search · graph · hash-table · leetcode · sliding-window · string · todo · Last updated: Aug 2, 2025

Maximum Size Subarray Sum equals K

January 26, 2024 · 1 min · array · hash-table · leetcode · prefix · prefix-sum · Last updated: Aug 15, 2025

Merge K Sorted Lists

January 26, 2024 · 8 min · bt-binary-tree · daily-coding-problem · divide-and-conquer · heap · heap-priority-queue · interviewbit · k-sorted · leetcode · linked-list · linkedlist · merge-sort · video · Last updated: Aug 2, 2025

Minimum Cost Tree From Leaf Values

January 26, 2024 · 11 min · array · bt-binary-tree · database · dynamic-programming · graph · greedy · hash-table · heap-priority-queue · leetcode · math · minimum-spanning-tree · monotonic-stack · sorting · stack · stack/monotonic · string · todo · topological-sort · union-find · Last updated: Aug 2, 2025

Minimum Insertion Steps to Make a String Palindrome

January 26, 2024 · 7 min · daily-coding-problem · dynamic-programming · leetcode · string · todo · Last updated: Jul 25, 2025

My Calendar 2

January 26, 2024 · 3 min · array · binary-search · design · leetcode · ordered-set · prefix-sum · segment-tree · todo · Last updated: Aug 2, 2025

Nim Game

January 26, 2024 · 4 min · brainteaser · game-theory · hash-table · leetcode · math · Last updated: Jul 31, 2025

Number of trailing zeros in a factorial

January 26, 2024 · 5 min · ctci · duplicates-algo · factorial · leetcode · math · moderate · todo · Last updated: Aug 1, 2025

Number of Wonderful Substrings

January 26, 2024 · 4 min · array · binary-search · bit-manipulation · combinatorics · database · dynamic-programming · graph · hash-table · leetcode · math · prefix-sum · simulation · sliding-window · string · todo · topological-sort · tree · Last updated: Aug 2, 2025

Odd Even Linked List - Bring odd nodes first and even later

January 26, 2024 · 3 min · leetcode · linked-list · linkedlist · todo · Last updated: Aug 2, 2025

Paint House 2 - N houses with k colors with no two adjacent houses with same color color

January 26, 2024 · 5 min · array · color · daily-coding-problem · dynamic-programming · leetcode · matrix · Last updated: Aug 2, 2025

Palindrome Pairs

January 26, 2024 · 6 min · array · hash-table · leetcode · pair_tuple · palindrome · string · trie · Last updated: Aug 2, 2025

Palindrome Partitioning II

January 26, 2024 · 6 min · dynamic-programming · leetcode · palindrome · partition · string · todo · Last updated: Aug 2, 2025

Palindrome Partitioning III

January 26, 2024 · 6 min · concurrency · dynamic-programming · leetcode · string · todo · Last updated: Aug 2, 2025

Palindrome Permutation

January 26, 2024 · 2 min · bit-manipulation · hash-table · leetcode · string · todo · Last updated: Aug 2, 2025

Partition List

January 26, 2024 · 4 min · leetcode · linked-list · linkedlist · partition · todo · two-pointers · Last updated: Aug 2, 2025

Partition to K Equal Sum Subsets Problem

January 26, 2024 · 2 min · array · backtracking · bit-manipulation · bitmask · dynamic-programming · leetcode · memoization · Last updated: Jun 14, 2024

Pascal’s Triangle 2 - Return nth row

January 26, 2024 · 2 min · array · dynamic-programming · leetcode · numerical-algo · pascal · triangle · Last updated: Aug 9, 2025

Peeking Iterator

January 26, 2024 · 3 min · array · design · iterator · leetcode · todo · Last updated: Aug 2, 2025

Populate next pointer to inorder successor in Binary Tree

January 26, 2024 · 5 min · ctci · bt-binary-tree · traversal/inorder · next · todo · traversal/reverse-inorder · Last updated: Mar 16, 2025

Populate next pointer to right node in Binary Tree

January 26, 2024 · 6 min · binary-tree · breadth-first-search · bt-binary-tree · depth-first-search · leetcode · linked-list · todo · tree · Last updated: Aug 2, 2025

Range Sum Query – Mutable

January 26, 2024 · 11 min · array · binary-indexed-tree · bt-binary-tree · design · fenwick-tree · leetcode · range-tree · segment-tree · Last updated: Aug 5, 2025

Range Sum Query 2D - Immutable

January 26, 2024 · 4 min · array · design · immutablity · leetcode · matrix · prefix-sum · segment-tree · todo · Last updated: Aug 2, 2025

Reconstruct Itinerary

January 26, 2024 · 5 min · backtracking · daily-coding-problem · depth-first-search · dfs · eulerian-circuit · graph · leetcode · Last updated: Aug 2, 2025

Rectangle Area - Total area of two rectangles

January 26, 2024 · 6 min · geometry · interval · leetcode · math · maths · rectangle · todo · Last updated: Aug 1, 2025

Remove Invalid Parentheses Problem

January 26, 2024 · 6 min · backtracking · breadth-first-search · leetcode · parentheses · string · string-algo · todo · Last updated: Nov 25, 2024

Remove K Digits

January 26, 2024 · 4 min · greedy · leetcode · monotonic-stack · stack · stack/monotonic · string · todo · Last updated: Aug 2, 2025

Remove Outermost Parentheses

January 26, 2024 · 3 min · binary-tree · depth-first-search · leetcode · parentheses · stack · string · todo · tree · Last updated: Aug 2, 2025

Reverse Bits

January 26, 2024 · 3 min · bit-manipulation · bits · divide-and-conquer · leetcode · reverse · video · Last updated: Aug 2, 2025

Reverse Words in a String 2

January 26, 2024 · 3 min · ctci · daily-coding-problem · leetcode · reverse · string · two-pointers · Last updated: Aug 2, 2025

Reverse Words in a String 3

January 26, 2024 · 2 min · leetcode · reverse · string · two-pointers · Last updated: Aug 2, 2025

Rotate n x n matrix by 90 degrees

January 26, 2024 · 11 min · array · array-algo · ctci · daily-coding-problem · interviewbit · leetcode · math · matrix · rotate · video · Last updated: Aug 2, 2025

Scramble String

January 26, 2024 · 12 min · dynamic-programming · leetcode · string · todo · Last updated: Aug 2, 2025

Search in Rotated Sorted Array 2 - Check if number exists - Duplicates allowed

January 26, 2024 · 2 min · array · binary-search · leetcode · rotated-sorted-array · todo · Last updated: Aug 2, 2025

Select Copy Paste 1 - Minimum operations

January 26, 2024 · 9 min · dynamic-programming · leetcode · math · max-min · video · Last updated: Aug 2, 2025

Serialize and Deserialize Binary Tree

January 26, 2024 · 5 min · binary-tree · breadth-first-search · bt-binary-tree · daily-coding-problem · depth-first-search · design · leetcode · serialization · string · todo · tree · Last updated: Mar 4, 2025

Shortest Palindrome 1 - Prepending characters

January 26, 2024 · 7 min · hash-function · leetcode · palindrome · rolling-hash · shortest-path · string · string-matching · todo · Last updated: Aug 2, 2025

Smallest K-Length Subsequence With Occurrences of a Letter

January 26, 2024 · 5 min · array · binary-indexed-tree · binary-search · bit-manipulation · bitmask · data-stream · design · divide-and-conquer · dynamic-programming · greedy · hash-table · heap-priority-queue · leetcode · math · matrix · merge-sort · monotonic-stack · ordered-set · segment-tree · sorting · stack · stack/monotonic · string · todo · two-pointers · Last updated: Aug 2, 2025

Sort Characters By Frequency

January 26, 2024 · 2 min · bucket-sort · counting · hash-table · heap-priority-queue · leetcode · sorting · string · Last updated: Aug 11, 2025

Spiral Matrix 1 - Return

January 26, 2024 · 6 min · array · daily-coding-problem · leetcode · matrix · simulation · spiral · todo · video · Last updated: Aug 2, 2025

Square root of an integer

January 26, 2024 · 4 min · binary-search · interviewbit · leetcode · math · search/binary · search/linear · Last updated: Jul 31, 2025

Strobogrammatic Number 1 - Check if strobogrammatic

January 26, 2024 · 2 min · hash-table · leetcode · string · two-pointers · Last updated: Aug 10, 2025

Strobogrammatic Number 2 - Generate for length n

January 26, 2024 · 2 min · array · daily-coding-problem · leetcode · recursion · string · Last updated: Aug 2, 2025

Strobogrammatic Number 3 - Count in Range

January 26, 2024 · 2 min · array · leetcode · recursion · string · Last updated: Aug 2, 2025

Student Attendance Record 1

January 26, 2024 · 2 min · leetcode · string · video · Last updated: Aug 2, 2025

Student Attendance Record 2

January 26, 2024 · 9 min · dynamic-programming · leetcode · string · Last updated: Aug 2, 2025

Subset Sum 1 - Is there a subset?

January 26, 2024 · 7 min · recursion · backtracking · dynamic-programming · sum · subset · Last updated: Aug 2, 2025

Sudoku Solver

January 26, 2024 · 4 min · array · backtracking · daily-coding-problem · hash-table · leetcode · matrix · sudoku · todo · Last updated: Aug 2, 2025

Sum of Beauty of All Substrings

January 26, 2024 · 3 min · array · binary-search · counting · database · graph · greedy · hash-table · leetcode · sorting · string · todo · two-pointers · Last updated: Aug 2, 2025

Surrounded Regions

January 26, 2024 · 14 min · array · breadth-first-search · depth-first-search · graph · leetcode · matrix · todo · union-find · Last updated: Aug 2, 2025

Swap Nodes in Pairs

January 26, 2024 · 2 min · daily-coding-problem · leetcode · linked-list · linkedlist · pair_tuple · recursion · swap · Last updated: Aug 2, 2025

Trips and Users Problem

January 26, 2024 · 4 min · database · leetcode · sql · todo · Last updated: Sep 26, 2024

Unique BSTs 2 - Generate

January 26, 2024 · 2 min · backtracking · binary-search-tree · binary-tree · dynamic-programming · leetcode · todo · tree · Last updated: Aug 2, 2025

Valid Number

January 26, 2024 · 2 min · daily-coding-problem · leetcode · string · todo · Last updated: Aug 2, 2025

Valid Parenthesis String

January 26, 2024 · 3 min · daily-coding-problem · dynamic-programming · greedy · leetcode · stack · string · Last updated: Aug 2, 2025

Valid Sudoku

January 26, 2024 · 6 min · array · game-development · games/sudoku · hash-table · leetcode · matrix · sudoku · to-publish · todo · Last updated: Aug 2, 2025

Validate Binary Search Tree

January 26, 2024 · 8 min · bfs · binary-search-tree · binary-tree · bst-binary-search-tree · daily-coding-problem · depth-first-search · dfs · leetcode · traversal/inorder · traversal/level-order · tree · Last updated: Aug 2, 2025

What is Java String’s Immutability

January 26, 2024 · 1 min · java · string · immutablity · video · Last updated: Mar 26, 2025

Word Break 2 - Construct a sentence

January 26, 2024 · 2 min · array · backtracking · daily-coding-problem · dfs · dynamic-programming · hash-table · leetcode · memoization · string · trie · video · word · word-break · Last updated: Aug 2, 2025

Zigzag Iterator

January 26, 2024 · 3 min · array · design · iterator · leetcode · queue · todo · Last updated: Aug 2, 2025

2023 ⁶⁸³

December ⁹

Validate IP Address

December 10, 2023 · 4 min · leetcode · string · Last updated: Aug 2, 2025

Convex Polygon

December 10, 2023 · 5 min · array · geometry · leetcode · math · Last updated: Aug 2, 2025

Encode String with Shortest Length

December 10, 2023 · 4 min · dynamic-programming · leetcode · string · Last updated: Aug 2, 2025

Generate Random Point in a Circle

December 10, 2023 · 4 min · geometry · leetcode · math · randomized · rejection-sampling · Last updated: Jul 31, 2025

Heaters Problem

December 10, 2023 · 7 min · array · binary-search · leetcode · sorting · two-pointers · Last updated: Nov 26, 2024

Implement Rand10() Using Rand7()

December 10, 2023 · 2 min · leetcode · math · probability-and-statistics · randomized · rejection-sampling · Last updated: Aug 2, 2025

Largest Palindrome Product

December 10, 2023 · 5 min · enumeration · leetcode · math · Last updated: Aug 2, 2025

Magical String

December 10, 2023 · 3 min · leetcode · string · two-pointers · Last updated: Aug 2, 2025

Sliding Window Median

December 10, 2023 · 5 min · array · hash-table · heap-priority-queue · leetcode · sliding-window · Last updated: Aug 11, 2025

November ²⁴⁵

Inorder Successor in Binary Tree

November 30, 2023 · 2 min · bt-binary-tree · traversal/inorder · Last updated: Aug 2, 2025

Sum of Absolute Differences in a Sorted Array

November 25, 2023 · 6 min · array · game-theory · greedy · heap-priority-queue · leetcode · math · prefix-sum · sorting · Last updated: Aug 2, 2025

Shortest Path in a Grid with Obstacles Elimination

November 24, 2023 · 8 min · array · breadth-first-search · leetcode · matrix · Last updated: Aug 2, 2025

Permutation in String

November 23, 2023 · 7 min · hash-table · leetcode · sliding-window · string · todo · two-pointers · Last updated: Aug 2, 2025

Can Make Arithmetic Progression From Sequence

November 23, 2023 · 2 min · array · brainteaser · dynamic-programming · leetcode · matrix · monotonic-stack · simulation · sorting · stack · Last updated: Aug 2, 2025

Check If It Is a Straight Line

November 23, 2023 · 3 min · array · geometry · leetcode · math · Last updated: Jul 31, 2025

Constrained Subsequence Sum

November 23, 2023 · 5 min · array · binary-search · binary-tree · breadth-first-search · data-stream · depth-first-search · design · dynamic-programming · hash-table · heap-priority-queue · interactive · leetcode · math · matrix · monotonic-queue · queue · sliding-window · string · tree · Last updated: Aug 2, 2025

Count Nice Pairs in an Array

November 23, 2023 · 4 min · array · binary-search · bit-manipulation · bitmask · counting · database · depth-first-search · dynamic-programming · graph · hash-table · leetcode · math · matrix · memoization · number-theory · ordered-set · sorting · string · Last updated: Aug 2, 2025

Count Unreachable Pairs of Nodes in an Undirected Graph

November 23, 2023 · 6 min · array · bit-manipulation · breadth-first-search · database · depth-first-search · dynamic-programming · graph · greedy · hash-table · leetcode · math · matrix · memoization · sorting · string · tree · union-find · Last updated: Aug 2, 2025

Find in Mountain Array

November 23, 2023 · 9 min · array · backtracking · binary-search · breadth-first-search · database · interactive · leetcode · stack · string · Last updated: Jul 31, 2025

Fruit Into Baskets

November 23, 2023 · 11 min · array · hash-table · leetcode · sliding-window · Last updated: Aug 9, 2025

Generate Fibonacci Sequence

November 23, 2023 · 2 min · leetcode · Last updated: Jul 31, 2025

Maximum Score of a Good Subarray

November 23, 2023 · 3 min · array · binary-search · greedy · hash-table · leetcode · monotonic-stack · stack · string · two-pointers · Last updated: Aug 2, 2025

Minimize Maximum of Array

November 23, 2023 · 3 min · array · binary-search · depth-first-search · dynamic-programming · enumeration · greedy · leetcode · math · prefix-sum · search/binary · todo · tree · Last updated: Aug 2, 2025

Minimum Amount of Time to Collect Garbage

November 23, 2023 · 7 min · array · leetcode · prefix-sum · string · Last updated: Aug 2, 2025

Nested Array Generator

November 23, 2023 · 2 min · array · backtracking · binary-indexed-tree · binary-search · binary-tree · bit-manipulation · breadth-first-search · database · depth-first-search · design · dynamic-programming · graph · greedy · hash-table · heap-priority-queue · leetcode · linked-list · math · matrix · number-theory · ordered-set · segment-tree · shortest-path · simulation · sliding-window · sorting · string · tree · two-pointers · union-find · Last updated: Aug 2, 2025

Number of Closed Islands

November 23, 2023 · 8 min · array · breadth-first-search · depth-first-search · leetcode · matrix · union-find · Last updated: Aug 2, 2025

Number of Flowers in Full Bloom

November 23, 2023 · 3 min · array · binary-search · database · design · hash-table · leetcode · ordered-set · prefix-sum · sorting · stack · string · Last updated: Aug 2, 2025

Number of Ways to Stay in the Same Place After Some Steps

November 23, 2023 · 5 min · array · breadth-first-search · database · depth-first-search · divide-and-conquer · dynamic-programming · interactive · leetcode · math · string · tree · Last updated: Aug 2, 2025

Painting the Walls

November 23, 2023 · 5 min · array · backtracking · binary-search · binary-tree · bit-manipulation · brainteaser · breadth-first-search · counting · database · depth-first-search · dynamic-programming · enumeration · greedy · hash-table · heap-priority-queue · interactive · leetcode · math · monotonic-queue · number-theory · ordered-set · prefix-sum · queue · simulation · sliding-window · sorting · stack · string · tree · union-find · Last updated: Aug 2, 2025

Parallel Courses III

November 23, 2023 · 7 min · array · database · dynamic-programming · graph · leetcode · topological-sort · Last updated: Jul 30, 2025

Remove Colored Pieces if Both Neighbors are the Same Color

November 23, 2023 · 4 min · game-theory · greedy · leetcode · math · string · Last updated: Aug 2, 2025

Removing Stars From a String

November 23, 2023 · 3 min · leetcode · simulation · stack · string · Last updated: Aug 2, 2025

Shuffle the Array

November 23, 2023 · 3 min · array · leetcode · sorting · todo · two-pointers · Last updated: Aug 2, 2025

Time Needed to Inform All Employees

November 23, 2023 · 4 min · breadth-first-search · depth-first-search · graph · leetcode · tree · Last updated: Aug 2, 2025

Sales Analysis II

November 23, 2023 · 2 min · array · database · hash-table · heap-priority-queue · leetcode · math · sorting · sql · Last updated: Jul 14, 2025

Remove All Adjacent Duplicates In String 1

November 23, 2023 · 2 min · leetcode · stack · string · Last updated: Jul 29, 2025

Diagonal Traverse 2

November 23, 2023 · 2 min · array · heap-priority-queue · leetcode · sorting · Last updated: Aug 2, 2025

Find Duplicate Subtrees

November 23, 2023 · 3 min · binary-tree · depth-first-search · hash-table · leetcode · traversal/postorder · tree · Last updated: Aug 2, 2025

Longest Subsequence With Limited Sum

November 23, 2023 · 5 min · array · binary-search · greedy · leetcode · prefix-sum · sorting · Last updated: Aug 2, 2025

Most Common Word

November 23, 2023 · 3 min · array · counting · hash-table · leetcode · string · Last updated: Aug 2, 2025

Removing Minimum and Maximum From Array

November 23, 2023 · 3 min · array · breadth-first-search · depth-first-search · enumeration · graph · greedy · hash-table · heap-priority-queue · leetcode · shortest-path · sorting · union-find · Last updated: Aug 2, 2025

Linked List Random Node

November 23, 2023 · 4 min · leetcode · linked-list · math · randomized · reservoir-sampling · Last updated: Aug 2, 2025

Max Area of Island

November 23, 2023 · 3 min · array · breadth-first-search · depth-first-search · dfs · disjoint-set · graph · leetcode · matrix · todo/add-dfs-visited-set · todo/add-union-find-sol · union-find · Last updated: Aug 2, 2025

A Number After a Double Reversal

November 23, 2023 · 2 min · array · hash-table · leetcode · math · prefix-sum · simulation · string · todo · Last updated: Aug 8, 2025

Count Number of Pairs With Absolute Difference K

November 23, 2023 · 5 min · 2sum · arithmetic-difference · array · array-algo · counting · hash-table · leetcode · pair_tuple · todo · Last updated: Aug 2, 2025

Cracking the Safe

November 23, 2023 · 5 min · depth-first-search · eulerian-circuit · graph · leetcode · Last updated: Aug 2, 2025

Exchange Seats Problem

November 23, 2023 · 2 min · database · leetcode · Last updated: Sep 26, 2024

Filter Elements from Array

November 23, 2023 · 4 min · array · combinatorics · dynamic-programming · leetcode · math · matrix · prefix-sum · sorting · Last updated: Aug 2, 2025

First Letter to Appear Twice

November 23, 2023 · 2 min · bit-manipulation · counting · hash-table · leetcode · string · Last updated: Jul 27, 2025

Longest Word in Dictionary through Deleting

November 23, 2023 · 8 min · array · leetcode · sorting · string · two-pointers · Last updated: Aug 2, 2025

Number of Excellent Pairs

November 23, 2023 · 4 min · array · binary-search · bit-manipulation · dynamic-programming · hash-table · leetcode · monotonic-stack · stack · Last updated: Jul 27, 2025

Prefix and Suffix Search

November 23, 2023 · 5 min · array · design · hash-table · leetcode · string · trie · Last updated: Jul 27, 2025

Search Suggestions System

November 23, 2023 · 6 min · array · binary-search · heap-priority-queue · leetcode · sorting · string · trie · Last updated: Aug 2, 2025

Count Good Meals

November 23, 2023 · 3 min · 2sum · array · binary-search · database · dynamic-programming · greedy · hash-table · hashing · leetcode · math · prefix-sum · two-pointers · Last updated: Aug 2, 2025

Binary Gap

November 23, 2023 · 2 min · bit-manipulation · leetcode · Last updated: Aug 2, 2025

Count Ways To Build Good Strings

November 23, 2023 · 4 min · array · breadth-first-search · depth-first-search · dynamic-programming · graph · leetcode · tree · Last updated: Aug 2, 2025

Find All K-Distant Indices in an Array

November 23, 2023 · 4 min · array · breadth-first-search · depth-first-search · graph · greedy · hash-table · leetcode · shortest-path · simulation · two-pointers · union-find · Last updated: Aug 2, 2025

Find First Palindromic String in the Array

November 23, 2023 · 2 min · array · binary-search · database · dynamic-programming · graph · greedy · hash-table · leetcode · math · simulation · stack · string · topological-sort · two-pointers · Last updated: Aug 2, 2025

Find the Difference of Two Arrays

November 23, 2023 · 3 min · array · greedy · hash-table · leetcode · math · stack · Last updated: Aug 2, 2025

Longest Binary Subsequence Less Than or Equal to K

November 23, 2023 · 5 min · array · binary-tree · database · depth-first-search · dynamic-programming · greedy · leetcode · memoization · string · tree · Last updated: Aug 2, 2025

Maximum Number of Points with Cost

November 23, 2023 · 5 min · array · bit-manipulation · counting · database · depth-first-search · dynamic-programming · hash-table · leetcode · matrix · string · todo · trie · Last updated: Aug 2, 2025

Maximum Performance of a Team

November 23, 2023 · 6 min · array · binary-search · bit-manipulation · database · dynamic-programming · greedy · hash-table · heap-priority-queue · leetcode · memoization · sorting · two-pointers · Last updated: Aug 2, 2025

Maximum Score from Performing Multiplication Operations

November 23, 2023 · 5 min · leetcode · Last updated: Aug 2, 2025

Number of Pairs of Strings With Concatenation Equal to Target

November 23, 2023 · 3 min · array · counting · hash-table · leetcode · string · Last updated: Aug 2, 2025

Numbers With Same Consecutive Differences

November 23, 2023 · 5 min · backtracking · breadth-first-search · leetcode · Last updated: Aug 2, 2025

Recover the Original Array

November 23, 2023 · 4 min · array · bit-manipulation · depth-first-search · enumeration · graph · greedy · hash-table · leetcode · math · matrix · sorting · string · topological-sort · two-pointers · Last updated: Aug 2, 2025

Sort the Matrix Diagonally

November 23, 2023 · 3 min · array · greedy · leetcode · math · matrix · sorting · Last updated: Aug 2, 2025

Find and Replace Pattern

November 23, 2023 · 3 min · array · hash-table · leetcode · string · Last updated: Jul 27, 2025

Design Skiplist

November 22, 2023 · 6 min · array · design · hash-table · leetcode · linked-list · Last updated: Aug 2, 2025

Human Traffic of Stadium

November 22, 2023 · 4 min · database · leetcode · sql · Last updated: Sep 26, 2024

Jump Game 6

November 22, 2023 · 5 min · array · dynamic-programming · heap-priority-queue · leetcode · monotonic-queue · queue · Last updated: Aug 2, 2025

Count Odd Numbers in an Interval Range

November 22, 2023 · 3 min · array · bit-manipulation · dynamic-programming · greedy · hash-table · leetcode · math · monotonic-stack · prefix-sum · stack · string · Last updated: Jul 31, 2025

Jump Game 4

November 22, 2023 · 6 min · array · binary-search · breadth-first-search · counting · design · hash-table · leetcode · ordered-set · sorting · string · two-pointers · Last updated: Aug 2, 2025

Minimize Deviation in Array

November 22, 2023 · 6 min · array · greedy · heap-priority-queue · leetcode · ordered-set · Last updated: Aug 2, 2025

Minimum Fuel Cost to Report to the Capital

November 22, 2023 · 5 min · array · breadth-first-search · database · depth-first-search · dynamic-programming · geometry · graph · leetcode · math · matrix · prefix-sum · simulation · string · tree · trie · Last updated: Aug 2, 2025

Minimum Time to Complete Trips

November 22, 2023 · 6 min · array · binary-search · counting · dynamic-programming · hash-table · leetcode · math · Last updated: Aug 2, 2025

Sum of Subarray Minimums

November 22, 2023 · 6 min · array · dynamic-programming · leetcode · monotonic-stack · stack · stack/monotonic · Last updated: Aug 2, 2025

Koko Eating Bananas

November 22, 2023 · 5 min · array · binary-search · leetcode · search/binary · Last updated: Aug 2, 2025

Check Completeness of a Binary Tree

November 21, 2023 · 3 min · binary-tree · breadth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Design Browser History

November 21, 2023 · 4 min · array · data-stream · design · doubly-linked-list · leetcode · linked-list · stack · Last updated: Jul 27, 2025

Kth Missing Positive Number

November 21, 2023 · 3 min · array · binary-search · greedy · hash-table · leetcode · stack · string · Last updated: Jul 29, 2025

Number of Provinces

November 21, 2023 · 5 min · breadth-first-search · depth-first-search · dfs · disjoint-set · graph · leetcode · union-find · Last updated: Aug 2, 2025

Number of Zero-Filled Subarrays

November 21, 2023 · 2 min · array · design · greedy · hash-table · heap-priority-queue · leetcode · math · ordered-set · Last updated: Aug 2, 2025

Shortest Path in Binary Matrix

November 21, 2023 · 4 min · array · bfs · breadth-first-search · leetcode · matrix · Last updated: Aug 2, 2025

Kids With the Greatest Number of Candies

November 21, 2023 · 2 min · array · greedy · leetcode · math · Last updated: Aug 2, 2025

Number of Operations to Make Network Connected

November 21, 2023 · 5 min · breadth-first-search · depth-first-search · disjoint-set · graph · leetcode · todo · union-find · Last updated: Aug 2, 2025

Checking Existence of Edge Length Limited Paths

November 21, 2023 · 7 min · array · database · graph · hash-function · leetcode · queue · rolling-hash · simulation · sorting · stack · string · suffix-array · trie · two-pointers · union-find · Last updated: Jul 30, 2025

Remove Max Number of Edges to Keep Graph Fully Traversable

November 21, 2023 · 5 min · array · database · disjoint-set · graph · greedy · leetcode · matrix · simulation · sorting · union-find · Last updated: Aug 2, 2025

Similar String Groups

November 21, 2023 · 4 min · array · breadth-first-search · depth-first-search · hash-table · leetcode · string · union-find · Last updated: Aug 2, 2025

Subarray Sum Equals K

November 21, 2023 · 6 min · array · daily-coding-problem · hash-table · leetcode · nsum · prefix-sum · Last updated: Aug 2, 2025

Apply Transform Over Each Element in Array Problem

November 19, 2023 · 2 min · leetcode · Last updated: Nov 27, 2024

Crawler Log Folder

November 19, 2023 · 3 min · array · depth-first-search · design · hash-table · leetcode · simulation · stack · string · tree · video · Last updated: Aug 2, 2025

Equal Row and Column Pairs

November 19, 2023 · 3 min · array · design · hash-table · heap-priority-queue · leetcode · matrix · ordered-set · simulation · Last updated: Jul 27, 2025

Find the Highest Altitude

November 19, 2023 · 3 min · array · binary-search · binary-tree · bit-manipulation · breadth-first-search · combinatorics · counting · depth-first-search · divide-and-conquer · dynamic-programming · greedy · hash-table · heap-priority-queue · leetcode · math · matrix · number-theory · prefix-sum · quickselect · sorting · string · tree · Last updated: Aug 2, 2025

K Radius Subarray Averages

November 19, 2023 · 6 min · array · leetcode · sliding-window · Last updated: Aug 2, 2025

Keys and Rooms

November 19, 2023 · 3 min · bfs · breadth-first-search · depth-first-search · graph · leetcode · Last updated: Aug 2, 2025

Number of Sub-arrays of Size K and Average Greater than or Equal to Threshold

November 19, 2023 · 4 min · array · leetcode · math · sliding-window · Last updated: Aug 2, 2025

Possible Bipartition

November 19, 2023 · 6 min · breadth-first-search · depth-first-search · graph · leetcode · union-find · Last updated: Aug 2, 2025

Print Binary Tree

November 19, 2023 · 4 min · binary-tree · breadth-first-search · bt-binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Snapshot Array

November 19, 2023 · 3 min · array · binary-search · design · hash-table · leetcode · Last updated: Jul 27, 2025

Sum of Distances in Tree

November 19, 2023 · 4 min · depth-first-search · dfs · dynamic-programming · graph · leetcode · traversal/postorder · traversal/preorder · tree · Last updated: Aug 2, 2025

Assign Cookies

November 19, 2023 · 5 min · array · greedy · leetcode · sorting · two-pointers · Last updated: Jul 14, 2025

Circular Array Loop

November 19, 2023 · 8 min · array · hash-table · leetcode · two-pointers · Last updated: Aug 1, 2025

Island Perimeter

November 19, 2023 · 6 min · array · bfs · breadth-first-search · depth-first-search · dfs · leetcode · matrix · video · Last updated: Aug 2, 2025

Minimum Moves to Equal Array Elements II

November 19, 2023 · 3 min · array · leetcode · math · sorting · Last updated: Aug 2, 2025

Minimum Number of Arrows to Burst Balloons

November 19, 2023 · 4 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Number of Boomerangs

November 19, 2023 · 4 min · array · hash-table · leetcode · math · Last updated: Jul 27, 2025

Optimal Account Balancing

November 19, 2023 · 8 min · array · backtracking · bit-manipulation · bitmask · dynamic-programming · leetcode · Last updated: Aug 1, 2025

All O`one Data Structure

November 18, 2023 · 7 min · design · doubly-linked-list · hash-table · hashmap · leetcode · linked-list · video · Last updated: Aug 10, 2025

Arithmetic Slices II - Subsequence

November 18, 2023 · 4 min · array · dynamic-programming · leetcode · Last updated: Aug 1, 2025

Encode N-ary Tree to Binary Tree

November 18, 2023 · 4 min · binary-tree · breadth-first-search · depth-first-search · design · leetcode · n-ary-tree · tree · Last updated: Aug 2, 2025

Find All Duplicates in an Array

November 18, 2023 · 4 min · array · hash-table · leetcode · Last updated: Jul 29, 2025

Find Right Interval

November 18, 2023 · 6 min · array · binary-search · leetcode · sorting · Last updated: Aug 1, 2025

Flatten a Multilevel Doubly Linked List

November 18, 2023 · 4 min · depth-first-search · doubly-linked-list · leetcode · linked-list · Last updated: Aug 2, 2025

K-th Smallest in Lexicographical Order

November 18, 2023 · 4 min · leetcode · trie · Last updated: Aug 2, 2025

Number of Segments in a String

November 18, 2023 · 4 min · leetcode · string · Last updated: Aug 2, 2025

Sequence Reconstruction

November 18, 2023 · 7 min · array · graph · leetcode · topological-sort · Last updated: Aug 2, 2025

Ternary Expression Parser

November 18, 2023 · 5 min · leetcode · recursion · stack · string · Last updated: Aug 2, 2025

Maximum XOR of Two Numbers in an Array

November 18, 2023 · 7 min · array · bit-manipulation · hash-table · leetcode · trie · Last updated: Aug 6, 2025

Reconstruct Original Digits from English

November 18, 2023 · 4 min · hash-table · leetcode · math · string · Last updated: Jul 27, 2025

Strong Password Checker

November 18, 2023 · 7 min · greedy · heap-priority-queue · leetcode · string · Last updated: Aug 2, 2025

Valid Word Square

November 18, 2023 · 4 min · array · leetcode · matrix · Last updated: Aug 2, 2025

Add Strings

November 18, 2023 · 5 min · cpp · golang · java · javascript · leetcode · math · python · rust · simulation · string · typescript · Last updated: Aug 2, 2025

Convert Number to Hexadecimal Number Problem

November 18, 2023 · 3 min · bit-manipulation · leetcode · math · number · number-system · Last updated: Nov 26, 2024

Minimum Unique Word Abbreviation

November 18, 2023 · 11 min · array · backtracking · bit-manipulation · leetcode · string · todo · Last updated: Aug 2, 2025

Trapping Rain Water 2

November 18, 2023 · 7 min · array · breadth-first-search · heap-priority-queue · leetcode · matrix · Last updated: Aug 2, 2025

Valid Word Abbreviation

November 18, 2023 · 5 min · leetcode · string · two-pointers · Last updated: Aug 2, 2025

Binary Watch

November 18, 2023 · 4 min · backtracking · bit-manipulation · bits · leetcode · Last updated: Aug 2, 2025

Maximum Subsequence Score

November 18, 2023 · 6 min · array · bit-manipulation · counting · dynamic-programming · greedy · hash-table · heap-priority-queue · leetcode · math · matrix · number-theory · recursion · simulation · sorting · string · todo · Last updated: Aug 2, 2025

Delete Columns to Make Sorted

November 15, 2023 · 4 min · array · leetcode · string · Last updated: Aug 2, 2025

Daily Temperatures

November 15, 2023 · 5 min · array · leetcode · monotonic-stack · stack · stack/monotonic · Last updated: Aug 2, 2025

Find Consecutive Integers from a Data Stream

November 15, 2023 · 3 min · counting · data-stream · design · hash-table · leetcode · queue · Last updated: Jul 28, 2025

Find Xor-Beauty of Array

November 15, 2023 · 3 min · array · binary-search · bit-manipulation · counting · greedy · leetcode · math · prefix-sum · queue · sliding-window · Last updated: Aug 2, 2025

Flip String to Monotone Increasing

November 15, 2023 · 2 min · dynamic-programming · leetcode · string · Last updated: Aug 2, 2025

Leaf-Similar Trees

November 15, 2023 · 3 min · binary-tree · depth-first-search · dfs · leetcode · traversal/preorder · tree · Last updated: Aug 2, 2025

Maximum Bags With Full Capacity of Rocks

November 15, 2023 · 4 min · array · counting · geometry · greedy · hash-table · leetcode · math · matrix · monotonic-stack · number-theory · prefix-sum · sorting · stack · string · Last updated: Aug 2, 2025

Non-decreasing Subsequences

November 15, 2023 · 4 min · array · backtracking · bit-manipulation · hash-table · leetcode · Last updated: Aug 2, 2025

Odd Even Jump

November 15, 2023 · 10 min · array · dynamic-programming · greedy · leetcode · math · monotonic-stack · ordered-set · sorting · stack · Last updated: Aug 2, 2025

Path Sum 3 - Count paths from parent to child

November 15, 2023 · 2 min · binary-tree · depth-first-search · dfs · leetcode · pathsum · prefix-sum · todo · tree · Last updated: Aug 2, 2025

Remove Stones to Minimize the Total

November 15, 2023 · 4 min · array · greedy · heap-priority-queue · leetcode · Last updated: Jul 31, 2025

Subarray Sums Divisible by K

November 15, 2023 · 7 min · array · hash-table · leetcode · modulo-operator · prefix-sum · video · Last updated: Aug 2, 2025

Swap For Longest Repeated Character Substring

November 15, 2023 · 7 min · hash-table · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Maximum Element After Decreasing and Rearranging

November 15, 2023 · 4 min · array · binary-search · greedy · leetcode · ordered-set · sorting · Last updated: Aug 2, 2025

Binary Trees With Factors

November 14, 2023 · 3 min · array · dynamic-programming · hash-table · leetcode · sorting · Last updated: Aug 2, 2025

Concatenation of Consecutive Binary Numbers

November 14, 2023 · 3 min · array · bit-manipulation · bitmask · dynamic-programming · leetcode · math · simulation · string · Last updated: Aug 2, 2025

Hamming Distance

November 14, 2023 · 4 min · bit-manipulation · leetcode · Last updated: Aug 2, 2025

Maximum Level Sum of a Binary Tree

November 14, 2023 · 2 min · bfs · binary-tree · breadth-first-search · depth-first-search · leetcode · traversal/level-order · tree · Last updated: Aug 2, 2025

Maximum Value at a Given Index in a Bounded Array

November 14, 2023 · 3 min · array · binary-search · bit-manipulation · design · greedy · hash-table · leetcode · math · number-theory · recursion · search/binary · simulation · string · trie · Last updated: Aug 2, 2025

Minimum Cost to Make Array Equal

November 14, 2023 · 4 min · array · binary-search · counting · greedy · hash-table · heap-priority-queue · leetcode · math · monotonic-stack · prefix-sum · sorting · stack · string · todo · Last updated: Aug 2, 2025

Minimum Flips to Make a OR b Equal to c

November 14, 2023 · 5 min · bit-manipulation · leetcode · Last updated: Aug 2, 2025

Number of Increasing Paths in a Grid

November 14, 2023 · 4 min · array · breadth-first-search · database · depth-first-search · dynamic-programming · graph · leetcode · matrix · memoization · string · todo · topological-sort · two-pointers · Last updated: Aug 2, 2025

Shortest Path to Get All Keys

November 14, 2023 · 5 min · array · bfs · bit-manipulation · breadth-first-search · leetcode · matrix · Last updated: Aug 2, 2025

Total Hamming Distance

November 14, 2023 · 4 min · array · bit-manipulation · leetcode · math · Last updated: Aug 18, 2025

Maximum Star Sum of a Graph

November 14, 2023 · 7 min · array · graph · greedy · heap-priority-queue · leetcode · sorting · Last updated: Jul 30, 2025

Maximum Value of a String in an Array

November 14, 2023 · 3 min · array · leetcode · string · Last updated: Aug 2, 2025

Number of Pairs of Interchangeable Rectangles

November 14, 2023 · 5 min · array · counting · hash-table · leetcode · math · number-theory · Last updated: Jul 31, 2025

Maximum Subarray Sum

November 14, 2023 · 5 min · array · daily-coding-problem · divide-and-conquer · divide-n-conquer · dynamic-programming · kadane · leetcode · sliding-window · sum · video · Last updated: Aug 2, 2025

Find the Index of the First Occurrence in a String

November 14, 2023 · 2 min · index · leetcode · pattern-matching · search · string · string-algo · string-matching · substring · to-publish · todo · two-pointers · Last updated: Aug 9, 2025

Time Based Key-Value Store

November 14, 2023 · 2 min · binary-search · daily-coding-problem · design · design/data-structure · hash-table · leetcode · string · Last updated: Aug 2, 2025

Add One Row to Tree

November 14, 2023 · 2 min · binary-tree · breadth-first-search · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Bulb Switcher II

November 14, 2023 · 8 min · bit-manipulation · breadth-first-search · depth-first-search · leetcode · math · Last updated: Jul 31, 2025

Matrix Block Sum

November 14, 2023 · 3 min · array · binary-tree · breadth-first-search · depth-first-search · hash-function · leetcode · math · matrix · prefix-sum · rolling-hash · string · tree · trie · Last updated: Aug 2, 2025

Maximum Sum of 3 Non-Overlapping Subarrays

November 14, 2023 · 5 min · array · dynamic-programming · leetcode · todo · Last updated: Aug 2, 2025

Minimum Increment to Make Array Unique

November 14, 2023 · 4 min · array · counting · greedy · leetcode · sorting · video · Last updated: Aug 2, 2025

Number of Good Leaf Nodes Pairs

November 14, 2023 · 6 min · binary-tree · bt-binary-tree · depth-first-search · leetcode · shortest-path · traversal/postorder · tree · video · Last updated: Aug 2, 2025

Hand of Straights

November 14, 2023 · 8 min · array · greedy · hash-table · hashing · heap/min · leetcode · sorting · video · Last updated: Aug 2, 2025

Add to Array-Form of Integer

November 14, 2023 · 3 min · array · leetcode · math · numerical-algo · Last updated: Aug 2, 2025

Fraction Addition and Subtraction

November 14, 2023 · 3 min · leetcode · math · maths · simulation · string · video · Last updated: Jul 31, 2025

Greatest Common Divisor of Strings

November 14, 2023 · 2 min · leetcode · math · string · todo · Last updated: Aug 2, 2025

K Inverse Pairs Array

November 14, 2023 · 5 min · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Maximum Difference Between Node and Ancestor

November 14, 2023 · 3 min · binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Minimum Number of Vertices to Reach All Nodes

November 14, 2023 · 4 min · array · binary-search · bit-manipulation · breadth-first-search · depth-first-search · game-theory · graph · greedy · hash-table · leetcode · math · matrix · simulation · sorting · union-find · Last updated: Jul 30, 2025

Mirror Reflection

November 14, 2023 · 5 min · geometry · leetcode · math · number-theory · Last updated: Jul 31, 2025

Convert Binary Search Tree to Sorted Doubly Linked List

November 13, 2023 · 4 min · binary-search-tree · binary-tree · depth-first-search · doubly-linked-list · leetcode · linked-list · stack · todo · tree · Last updated: Aug 2, 2025

Deepest Leaves Sum

November 13, 2023 · 2 min · binary-tree · breadth-first-search · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Sort Vowels in a String

November 13, 2023 · 5 min · array · binary-search · binary-tree · bit-manipulation · bitmask · depth-first-search · divide-and-conquer · dynamic-programming · enumeration · greedy · hash-table · leetcode · math · sliding-window · sorting · string · tree · Last updated: Aug 2, 2025

Verifying an Alien Dictionary

November 13, 2023 · 4 min · array · hash-table · leetcode · string · Last updated: Jul 27, 2025

Sparse Matrix Multiplication

November 13, 2023 · 2 min · array · hash-table · leetcode · matrix · Last updated: Aug 2, 2025

Vertical Order Traversal of a Binary Tree

November 13, 2023 · 7 min · backtracking · binary-tree · breadth-first-search · bt-binary-tree · depth-first-search · hash-table · interviewbit · leetcode · sorting · string · traversal · tree · vertical · Last updated: Aug 2, 2025

Find Duplicate File in System

November 13, 2023 · 3 min · array · hash-table · hashing · leetcode · string · Last updated: Aug 2, 2025

Bag of Tokens

November 13, 2023 · 5 min · array · greedy · leetcode · sorting · todo · two-pointers · Last updated: Aug 2, 2025

Longest Palindrome by Concatenating Two Letter Words

November 13, 2023 · 3 min · array · counting · greedy · hash-table · leetcode · matrix · prefix-sum · string · todo · Last updated: Aug 2, 2025

Minimum Genetic Mutation

November 13, 2023 · 4 min · breadth-first-search · hash-table · leetcode · string · todo · Last updated: Aug 2, 2025

N-ary Tree Level Order Traversal

November 13, 2023 · 2 min · breadth-first-search · leetcode · tree · Last updated: Aug 2, 2025

N-ary Tree Postorder Traversal

November 13, 2023 · 3 min · depth-first-search · dfs · leetcode · n-ary-tree · stack · tree · video · Last updated: Aug 2, 2025

N-ary Tree Preorder Traversal

November 13, 2023 · 1 min · depth-first-search · dfs · leetcode · n-ary-tree · stack · tree · Last updated: Aug 2, 2025

Reverse String 2

November 13, 2023 · 1 min · leetcode · reverse · string · two-pointers · Last updated: Aug 2, 2025

The Time When the Network Becomes Idle

November 13, 2023 · 9 min · array · bfs · binary-search · breadth-first-search · database · design · graph · hash-table · leetcode · simulation · string · Last updated: Aug 2, 2025

Find Closest Node to Given Two Nodes

November 12, 2023 · 4 min · depth-first-search · graph · leetcode · todo · Last updated: Aug 2, 2025

Find the Town Judge

November 12, 2023 · 3 min · array · binary-tree · graph · hash-table · hashing · leetcode · matrix · simulation · todo · tree · Last updated: Jul 27, 2025

Most Stones Removed with Same Row or Column

November 12, 2023 · 7 min · depth-first-search · graph · hash-table · leetcode · strongly-connected-components · union-find · video · Last updated: Aug 2, 2025

N-th Tribonacci Number

November 12, 2023 · 3 min · array · dynamic-programming · hash-table · leetcode · math · matrix · memoization · string · Last updated: Jul 31, 2025

Bus Routes

November 12, 2023 · 7 min · array · bfs · breadth-first-search · hash-table · leetcode · Last updated: Aug 2, 2025

Design Graph With Shortest Path Calculator

November 11, 2023 · 5 min · design · dijkstra · graph · heap-priority-queue · leetcode · shortest-path · Last updated: Jul 27, 2025

Restore the Array From Adjacent Pairs

November 10, 2023 · 4 min · array · counting · database · depth-first-search · dynamic-programming · hash-table · leetcode · prefix-sum · string · two-pointers · Last updated: Jul 27, 2025

As Far from Land as Possible

November 10, 2023 · 8 min · array · binary-search · breadth-first-search · database · design · dynamic-programming · graph · greedy · hash-table · heap-priority-queue · leetcode · linked-list · matrix · minimum-spanning-tree · sorting · stack · string · trie · two-pointers · union-find · Last updated: Jul 31, 2025

Lexicographically Smallest Equivalent String

November 10, 2023 · 6 min · array · backtracking · binary-search · bit-manipulation · bitmask · database · dynamic-programming · hash-function · leetcode · math · monotonic-stack · rolling-hash · sorting · stack · string · suffix-array · trie · union-find · Last updated: Aug 2, 2025

Longest Path With Different Adjacent Characters

November 10, 2023 · 11 min · array · binary-indexed-tree · binary-search · bit-manipulation · bitmask · counting · depth-first-search · dynamic-programming · enumeration · geometry · graph · hash-table · leetcode · math · sorting · string · topological-sort · tree · Last updated: Aug 2, 2025

Naming a Company

November 10, 2023 · 4 min · array · bit-manipulation · database · depth-first-search · dynamic-programming · enumeration · graph · greedy · hash-table · leetcode · math · string · union-find · Last updated: Aug 2, 2025

Number of Good Paths

November 10, 2023 · 9 min · array · binary-indexed-tree · binary-search · bit-manipulation · brainteaser · counting · design · disjoint-set · divide-and-conquer · dynamic-programming · enumeration · graph · greedy · hash-function · hash-table · heap-priority-queue · leetcode · math · matrix · merge-sort · number-theory · ordered-set · prefix-sum · rolling-hash · segment-tree · sorting · stack · string · string-matching · todo · tree · two-pointers · union-find · Last updated: Aug 2, 2025

Number of Nodes in the Sub-Tree With the Same Label

November 10, 2023 · 6 min · breadth-first-search · counting · depth-first-search · greedy · hash-table · leetcode · string · tree · Last updated: Aug 2, 2025

Shortest Path with Alternating Colors

November 10, 2023 · 8 min · breadth-first-search · graph · leetcode · Last updated: Jul 29, 2025

Decimal to Binary Number Conversion

November 10, 2023 · 1 min · todo · number · number-system · video · Last updated: Nov 3, 2024

Battleships in a Board

November 9, 2023 · 9 min · array · depth-first-search · leetcode · matrix · Last updated: Aug 1, 2025

Evaluate Division

November 9, 2023 · 4 min · array · breadth-first-search · depth-first-search · graph · leetcode · shortest-path · string · union-find · Last updated: Aug 2, 2025

Integer Replacement

November 9, 2023 · 4 min · bit-manipulation · dynamic-programming · greedy · leetcode · memoization · Last updated: Aug 2, 2025

Longest Substring with At Least K Repeating Characters

November 9, 2023 · 3 min · divide-and-conquer · hash-table · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Maximum 69 Number

November 9, 2023 · 4 min · array · greedy · leetcode · math · simulation · string · Last updated: Aug 17, 2025

Minimum Time Difference

November 9, 2023 · 3 min · array · leetcode · math · sorting · string · todo · video · Last updated: Aug 2, 2025

Nth Digit

November 9, 2023 · 4 min · binary-search · leetcode · math · todo · Last updated: Jul 31, 2025

Orderly Queue

November 9, 2023 · 3 min · leetcode · math · sorting · string · Last updated: Aug 2, 2025

Perfect Rectangle

November 9, 2023 · 6 min · array · leetcode · line-sweep · Last updated: Jul 31, 2025

Rotate Function

November 9, 2023 · 5 min · array · dynamic-programming · leetcode · math · Last updated: Aug 2, 2025

Valid Square

November 9, 2023 · 3 min · geometry · leetcode · math · maths · Last updated: Aug 2, 2025

Minimum Rounds to Complete All Tasks

November 9, 2023 · 4 min · array · counting · greedy · hash-table · leetcode · matrix · prefix-sum · Last updated: Aug 2, 2025

Sum of All Odd Length Subarrays

November 9, 2023 · 3 min · array · greedy · leetcode · math · prefix-sum · sorting · Last updated: Aug 2, 2025

Online Stock Span

November 9, 2023 · 3 min · data-stream · design · leetcode · monotonic-stack · stack · stack/monotonic · Last updated: Aug 2, 2025

Count Number of Homogenous Substrings

November 9, 2023 · 3 min · array · binary-search · bit-manipulation · breadth-first-search · database · depth-first-search · divide-and-conquer · graph · greedy · hash-table · leetcode · math · matrix · monotonic-stack · number-theory · prefix-sum · sliding-window · stack · string · string-matching · tree · two-pointers · Last updated: Aug 2, 2025

Game Analysis IV

November 9, 2023 · 4 min · database · leetcode · sql · Last updated: Sep 26, 2024

Game Play Analysis V

November 9, 2023 · 2 min · database · leetcode · sql · Last updated: Sep 26, 2024

Most Frequent Subtree Sum

November 9, 2023 · 3 min · binary-tree · daily-coding-problem · depth-first-search · dfs · hash-table · leetcode · tree · Last updated: Aug 2, 2025

Toeplitz Matrix

November 9, 2023 · 2 min · array · leetcode · matrix · todo · Last updated: Aug 2, 2025

Delete the Middle Node of a Linked List

November 8, 2023 · 3 min · leetcode · linked-list · linkedlist · two-pointers · Last updated: Aug 2, 2025

Check if the Sentence Is Pangram

November 8, 2023 · 2 min · array · counting-sort · greedy · hash-table · hashing · leetcode · sorting · string · todo · Last updated: Jul 27, 2025

Design Circular Deque

November 8, 2023 · 8 min · array · design · design/data-structure · leetcode · linked-list · queue · video · Last updated: Aug 2, 2025

Image Overlap

November 8, 2023 · 4 min · array · leetcode · matrix · Last updated: Aug 2, 2025

Maximize Score After N Operations

November 8, 2023 · 9 min · array · backtracking · bit-manipulation · bitmask · dynamic-programming · heap-priority-queue · leetcode · math · number-theory · simulation · todo · Last updated: Aug 2, 2025

Set Mismatch

November 8, 2023 · 4 min · array · bit-manipulation · hash-table · leetcode · sorting · todo · Last updated: Jul 29, 2025

Determine if a Cell Is Reachable at a Given Time

November 8, 2023 · 4 min · array · binary-indexed-tree · binary-search · bit-manipulation · breadth-first-search · combinatorics · counting · database · depth-first-search · dynamic-programming · enumeration · game-theory · graph · greedy · hash-table · leetcode · math · matrix · memoization · monotonic-stack · number-theory · prefix-sum · segment-tree · simulation · sliding-window · sorting · stack · string · string-matching · tree · two-pointers · union-find · Last updated: Aug 1, 2025

Peak Index in a Mountain Array

November 8, 2023 · 3 min · array · binary-search · bitonic · bst-binary-search-tree · leetcode · Last updated: Aug 2, 2025

Design Phone Directory

November 7, 2023 · 3 min · array · design · hash-table · leetcode · linked-list · queue · todo · Last updated: Jul 27, 2025

Elimination Game

November 7, 2023 · 5 min · leetcode · math · recursion · todo · Last updated: Jul 31, 2025

Lexicographical Numbers

November 7, 2023 · 4 min · depth-first-search · dfs · java · leetcode · python · todo · trie · video · Last updated: Aug 2, 2025

Mini Parser

November 7, 2023 · 4 min · depth-first-search · leetcode · stack · string · todo · Last updated: Aug 2, 2025

Super Pow

November 7, 2023 · 5 min · divide-and-conquer · leetcode · math · todo · Last updated: Aug 2, 2025

N-Queens 2 - Count number of distinct solutions

November 7, 2023 · 4 min · backtracking · leetcode · Last updated: Aug 2, 2025

Make The String Great

November 7, 2023 · 2 min · leetcode · stack · string · video · Last updated: Aug 2, 2025

Minimum Cost to Move Chips to The Same Position

November 7, 2023 · 3 min · array · greedy · leetcode · math · maths · Last updated: Aug 2, 2025

Minimum Subsequence in Non-Increasing Order

November 7, 2023 · 4 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Shortest Way to Form String

November 7, 2023 · 3 min · array · binary-search · graph · greedy · leetcode · math · sorting · string · todo · topological-sort · two-pointers · Last updated: Aug 2, 2025

Find Nearest Point That Has the Same X or Y Coordinate

November 7, 2023 · 5 min · array · coordinate-geometry · leetcode · math · Last updated: Jul 31, 2025

Find Numbers with Even Number of Digits

November 7, 2023 · 5 min · array · leetcode · math · Last updated: Aug 2, 2025

Longest Univalue Path

November 7, 2023 · 3 min · binary-tree · depth-first-search · leetcode · tree · univalue-tree · Last updated: Aug 2, 2025

Univalued Binary Tree

November 7, 2023 · 2 min · array · binary-tree · breadth-first-search · depth-first-search · hash-table · leetcode · string · tree · univalue-tree · Last updated: Aug 2, 2025

Arrange Given Number To Form The Biggest Number Possible

November 7, 2023 · 2 min · number · sorting · Last updated: Jul 31, 2025

Day of the Year

November 7, 2023 · 3 min · leetcode · math · numerical-algo · string · todo · Last updated: Aug 2, 2025

Range Addition 2

November 7, 2023 · 2 min · array · leetcode · math · maths · Last updated: Aug 2, 2025

Minimum Moves to Equal Array Elements

November 7, 2023 · 2 min · array · leetcode · math · maths · Last updated: Aug 2, 2025

Prime Arrangements

November 7, 2023 · 6 min · array · leetcode · math · maths · sliding-window · todo · Last updated: Aug 2, 2025

Valid Boomerang

November 7, 2023 · 3 min · array · coordinate-geometry · geometry · leetcode · math · maths · Last updated: Jul 31, 2025

Largest Time for Given Digits

November 6, 2023 · 3 min · array · enumeration · leetcode · string · todo · Last updated: Aug 2, 2025

Minimum Health to Beat Game

November 6, 2023 · 5 min · array · greedy · leetcode · Last updated: Aug 2, 2025

Next Greater Element 2

November 6, 2023 · 2 min · array · leetcode · monotonic-stack · stack · stack/monotonic · Last updated: Aug 2, 2025

Find the Winner of an Array Game

November 5, 2023 · 6 min · array · dynamic-programming · greedy · interactive · leetcode · math · matrix · simulation · two-pointers · Last updated: Aug 2, 2025

October ²

Backspace String Compare

October 19, 2023 · 2 min · leetcode · simulation · stack · string · two-pointers · Last updated: Aug 2, 2025

132 Pattern

October 1, 2023 · 6 min · array · binary-search · leetcode · monotonic-stack · ordered-set · stack · stack/monotonic · Last updated: Aug 2, 2025

September ¹¹

Decoded String at Index

September 27, 2023 · 3 min · leetcode · stack · string · Last updated: Aug 2, 2025

Report an Issue

September 25, 2023 ·

Find the Difference

September 25, 2023 · 4 min · bit-manipulation · hash-table · leetcode · sorting · string · todo · Last updated: Aug 2, 2025

Code Formatter

September 15, 2023 · 1 min ·

Online UUID Generator

September 15, 2023 · 1 min ·

Range Addition

September 14, 2023 · 4 min · array · bt-binary-tree · leetcode · prefix-sum · Last updated: Aug 2, 2025

Valid Perfect Square

September 14, 2023 · 2 min · binary-search · leetcode · math · numerical-algo · search/binary · Last updated: Aug 2, 2025

Nested List Weight Sum 2

September 14, 2023 · 5 min · breadth-first-search · depth-first-search · leetcode · stack · Last updated: Aug 2, 2025

Design Hit Counter

September 14, 2023 · 3 min · array · binary-search · daily-coding-problem · data-stream · design · leetcode · queue · todo · Last updated: Aug 2, 2025

About Me

September 11, 2023 · 1 min ·

Privacy Policy

September 9, 2023 ·

August ⁶²

Rearrange String k Distance Apart

August 27, 2023 · 3 min · counting · greedy · hash-table · heap-priority-queue · heap/max · leetcode · sorting · string · Last updated: Aug 2, 2025

Sales Person Problem

August 25, 2023 · 5 min · database · leetcode · Last updated: Sep 26, 2024

Managers with at Least 5 Direct Reports Problem

August 25, 2023 · 2 min · database · leetcode · pandas · sql · Last updated: Sep 26, 2024

Students and Examinations Problem

August 25, 2023 · 4 min · array · database · greedy · hash-table · leetcode · math · pandas · sql · Last updated: Sep 26, 2024

Replace Employee ID With The Unique Identifier Problem

August 25, 2023 · 2 min · database · leetcode · pandas · sql · Last updated: Sep 26, 2024

Actors and Directors Who Cooperated At Least Three Times Problem

August 25, 2023 · 2 min · database · leetcode · pandas · sql · Last updated: Sep 26, 2024

Leetcode 1693 - Daily Leads and Partners

August 25, 2023 · 2 min · database · leetcode · pandas · sql · string · Last updated: Sep 26, 2024

Group Sold Products By The Date Problem

August 25, 2023 · 1 min · array · binary-search · binary-tree · bit-manipulation · breadth-first-search · database · depth-first-search · greedy · hash-table · heap-priority-queue · leetcode · math · sql · string · tree · Last updated: Sep 26, 2024

Customer Placing the Largest Number of Orders Problem

August 25, 2023 · 2 min · database · leetcode · pandas · sql · Last updated: Sep 26, 2024

Classes More Than 5 Students Problem

August 24, 2023 · 2 min · database · leetcode · pandas · sql · Last updated: Sep 26, 2024

Reorganize String

August 23, 2023 · 7 min · adjacent · array-algo · counting · greedy · hash-table · hashing · heap · heap-priority-queue · leetcode · rearrange-array · sorting · string · string-algo · Last updated: Aug 11, 2025

Number of Unique Subjects Taught by Each Teacher Problem

August 22, 2023 · 2 min · database · leetcode · pandas · sql · Last updated: Sep 26, 2024

Game Play Analysis I

August 22, 2023 · 2 min · database · leetcode · pandas · sql · Last updated: Sep 26, 2024

Find Total Time Spent by Each Employee Problem

August 22, 2023 · 3 min · counting · database · hash-table · leetcode · math · pandas · sql · Last updated: Sep 26, 2024

Binary Tree Bottom View

August 18, 2023 · 4 min · views · bt-binary-tree · traversal · traversal/level-order · Last updated: Aug 2, 2025

Find Vertical Sum in binary Tree

August 18, 2023 · 3 min · bt-binary-tree · traversal · traversal/level-order · vertical · Last updated: Aug 2, 2025

Count Salary Categories Problem

August 17, 2023 · 3 min · array · bit-manipulation · brainteaser · database · dynamic-programming · game-theory · leetcode · math · pandas · simulation · sql · stack · string · Last updated: Sep 26, 2024

Immediate Food Delivery I

August 17, 2023 · 2 min · database · leetcode · pandas · sql · Last updated: Sep 26, 2024

The number of Rich Customers Problem

August 17, 2023 · 2 min · array · binary-search · counting · database · dynamic-programming · greedy · hash-table · leetcode · math · matrix · pandas · prefix-sum · sorting · sql · string · Last updated: Sep 26, 2024

Recyclable and Low Fat Products Problem

August 17, 2023 · 2 min · database · leetcode · string · Last updated: Sep 26, 2024

01 Matrix

August 17, 2023 · 2 min · array · bfs · binary-matrix · breadth-first-search · dynamic-programming · leetcode · matrix · Last updated: Aug 2, 2025

Flatten Nested List Iterator

August 16, 2023 · 5 min · depth-first-search · design · iterator · leetcode · queue · stack · tree · Last updated: Aug 2, 2025

Smallest Rectangle Enclosing Black Pixels

August 16, 2023 · 4 min · array · binary-search · breadth-first-search · depth-first-search · leetcode · matrix · Last updated: Aug 2, 2025

Unique Word Abbreviation

August 16, 2023 · 4 min · array · design · hash-table · leetcode · string · Last updated: Aug 2, 2025

Shortest Word Distance 3

August 16, 2023 · 3 min · array · leetcode · string · Last updated: Aug 2, 2025

Shortest Word Distance 2

August 16, 2023 · 3 min · array · design · hash-table · leetcode · shortest-path · string · two-pointers · Last updated: Aug 2, 2025

Shortest Word Distance 1

August 16, 2023 · 5 min · array · array-algo · ctci · distance · leetcode · max-min · shortest-path · string · Last updated: Aug 2, 2025

Android Unlock Patterns

August 16, 2023 · 5 min · backtracking · bit-manipulation · bitmask · daily-coding-problem · dfs · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Intersection of Two Arrays 2 - Duplicates allowed

August 16, 2023 · 4 min · array · array-algo · binary-search · external-sort · hash-table · hashing · intersection · leetcode · sorting · two-array · two-pointers · Last updated: Aug 2, 2025

Intersection of Two Arrays 1 - Unique Elements

August 16, 2023 · 3 min · array · array-algo · binary-search · hash-table · intersection · leetcode · search/binary · sorting · two-array · two-pointers · video · Last updated: Aug 2, 2025

Design Tic-Tac-Toe

August 16, 2023 · 10 min · array · design · game-development · games/tic-tac-toe · hash-table · leetcode · matrix · simulation · Last updated: Aug 2, 2025

Longest Substring with At Most K Distinct Characters

August 16, 2023 · 1 min · daily-coding-problem · hash-table · leetcode · sliding-window · string · Last updated: Aug 2, 2025

Nested List Weight Sum

August 16, 2023 · 5 min · breadth-first-search · depth-first-search · hash-table · leetcode · Last updated: Aug 2, 2025

Largest Binary Search Tree BST Subtree

August 16, 2023 · 3 min · binary-search-tree · binary-tree · bst-binary-search-tree · bt-binary-tree · daily-coding-problem · depth-first-search · dynamic-programming · leetcode · tree · Last updated: Aug 2, 2025

Generalized Abbreviation

August 16, 2023 · 3 min · backtracking · bit-manipulation · leetcode · string · Last updated: Aug 2, 2025

House Robber 3 - Houses in Binary Tree

August 16, 2023 · 3 min · binary-tree · bt-binary-tree · depth-first-search · dfs · dynamic-programming · leetcode · tree · Last updated: Aug 2, 2025

Maximum Product of Word Lengths

August 16, 2023 · 5 min · array · bit-manipulation · bits · leetcode · max-min · string · string-algo · Last updated: Aug 2, 2025

Minimum Height Trees

August 16, 2023 · 4 min · breadth-first-search · bt-binary-tree · depth-first-search · graph · leetcode · topological-sort · Last updated: Aug 2, 2025

Remove Duplicate Letters

August 16, 2023 · 5 min · greedy · leetcode · monotonic-stack · stack · stack/monotonic · string · Last updated: Aug 2, 2025

Burst Balloons

August 16, 2023 · 9 min · array · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Binary Tree Longest Consecutive Sequence

August 16, 2023 · 4 min · binary-tree · bt-binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Longest Consecutive Sequence

August 16, 2023 · 3 min · array · consecutive · daily-coding-problem · hash-table · leetcode · longest · subsequence · union-find · Last updated: Aug 2, 2025

Find the Celebrity

August 16, 2023 · 4 min · daily-coding-problem · directed-graph · graph · interactive · leetcode · matrix · two-pointers · Last updated: Aug 10, 2025

Group Shifted Strings

August 16, 2023 · 3 min · array · hash-table · leetcode · string · Last updated: Aug 2, 2025

Bitwise AND of Numbers Range

August 16, 2023 · 2 min · bit-manipulation · bits · leetcode · Last updated: Aug 2, 2025

Rearrange Products Table Problem

August 14, 2023 · 3 min · array · database · design · doubly-linked-list · greedy · hash-table · leetcode · linked-list · pandas · sorting · sql · string · Last updated: Sep 26, 2024

Delete Duplicate Emails Problem

August 14, 2023 · 3 min · database · leetcode · pandas · sql · Last updated: Sep 25, 2024

Rank Scores

August 14, 2023 · 4 min · database · leetcode · pandas · sql · Last updated: Aug 2, 2025

Department Highest Salary Problem

August 13, 2023 · 3 min · database · leetcode · pandas · sql · Last updated: Sep 26, 2024

Second Highest Salary Problem

August 13, 2023 · 2 min · database · leetcode · sql · Last updated: Sep 25, 2024

Nth Highest Salary Problem

August 13, 2023 · 2 min · database · leetcode · pandas · sql · Last updated: Sep 25, 2024

Check if There is a Valid Partition For The Array

August 13, 2023 · 2 min · array · database · dynamic-programming · graph · hash-table · leetcode · matrix · sorting · string · topological-sort · union-find · Last updated: Aug 2, 2025

Leetcode 1527 - Patients With a Condition

August 13, 2023 · 2 min · array · database · greedy · leetcode · pandas · sql · string · Last updated: Sep 26, 2024

Find Users With Valid E-Mails Problem

August 12, 2023 · 3 min · database · leetcode · sql · Last updated: Sep 26, 2024

Leetcode 1667 - Fix Names in a Table

August 12, 2023 · 1 min · array · data-stream · database · design · dynamic-programming · leetcode · linked-list · queue · sql · string · string-matching · Last updated: Sep 26, 2024

Leetcode 1873 - Calculate Special Bonus

August 12, 2023 · 2 min · array · bit-manipulation · bitmask · counting · database · dynamic-programming · greedy · hash-table · heap-priority-queue · leetcode · math · matrix · prefix-sum · sliding-window · sorting · sql · string · two-pointers · Last updated: Sep 26, 2024

Leetcode 1683 - Invalid Tweets

August 12, 2023 · 2 min · database · leetcode · sql · Last updated: Sep 26, 2024

Leetcode 1148 - Article Views I

August 12, 2023 · 1 min · array · binary-search · database · leetcode · sql · Last updated: Sep 26, 2024

Ad-Free Sessions Problem

August 12, 2023 · 1 min · breadth-first-search · database · depth-first-search · graph · heap-priority-queue · interactive · leetcode · math · sql · string · Last updated: Sep 26, 2024

Customers Who Never Order Problem

August 12, 2023 · 3 min · database · leetcode · pandas · sql · Last updated: Sep 26, 2024

Big Countries Problem

August 11, 2023 · 2 min · database · leetcode · pandas · sql · Last updated: Sep 26, 2024

URL vs URI vs URN

August 9, 2023 · 3 min · Last updated: Jul 23, 2025

July ¹⁶

Predict the Winner

July 28, 2023 · 6 min · array · dynamic-programming · game-theory · leetcode · math · recursion · Last updated: Aug 2, 2025

Knight Probability in Chessboard

July 23, 2023 · 9 min · dynamic-programming · leetcode · Last updated: Aug 10, 2025

Asteroid Collision

July 20, 2023 · 3 min · array · leetcode · simulation · stack · Last updated: Aug 2, 2025

Add Two Numbers represented as Linked List in Forward order

July 17, 2023 · 5 min · leetcode · linked-list · math · stack · Last updated: Aug 2, 2025

Add Two Numbers represented as Linked List

July 17, 2023 · 1 min · ctci · linkedlist · numerical-algo · add · Last updated: Aug 2, 2025

URL Structure

July 16, 2023 · 2 min · Last updated: Jul 19, 2024

Course Schedule 1 - Is it Possible

July 13, 2023 · 3 min · breadth-first-search · depth-first-search · graph · leetcode · schedule · topological-sort · Last updated: Aug 2, 2025

Course Schedule 2 - Get Ordered Courses

July 13, 2023 · 6 min · breadth-first-search · daily-coding-problem · depth-first-search · graph · leetcode · topological-sort · Last updated: Aug 2, 2025

All Nodes Distance K in Binary Tree

July 11, 2023 · 4 min · binary-tree · breadth-first-search · depth-first-search · hash-table · leetcode · tree · Last updated: Aug 2, 2025

Minimum Depth of Binary Tree

July 10, 2023 · 2 min · binary-tree · breadth-first-search · bt-binary-tree · depth · depth-first-search · height · leetcode · max-min · todo · tree · Last updated: Aug 2, 2025

Substring with Largest Variance

July 9, 2023 · 4 min · array · dynamic-programming · hash-table · leetcode · sorting · string · Last updated: Aug 2, 2025

Single Number 2 - All elements except one occur thrice

July 7, 2023 · 6 min · array · array-algo · bit-manipulation · bits · daily-coding-problem · duplicates-algo · leetcode · non-duplicated-algo · repeat · xor · Last updated: Aug 2, 2025

Kth Largest Element in an Array

July 3, 2023 · 4 min · array · array-algo · divide-and-conquer · heap-priority-queue · heap/max · heap/min · k-smallest-largest · kth · leetcode · quickselect · sorting · Last updated: Aug 2, 2025

Kth Smallest Element in an Array

July 3, 2023 · 19 min · array · array-algo · divide-and-conquer · heap-priority-queue · heap/min · k-smallest-largest · kth · leetcode · quickselect · sorting · Last updated: Jul 23, 2025

Restore IP Addresses

July 3, 2023 · 3 min · backtracking · leetcode · string · Last updated: Aug 2, 2025

Divide Two Integers

July 1, 2023 · 5 min · bit-manipulation · daily-coding-problem · integer · java · leetcode · math · Last updated: Aug 11, 2025

June ²

URL Query Strings

June 16, 2023 · 1 min · Last updated: Jul 19, 2024

Minimum Absolute Difference in BST

June 14, 2023 · 3 min · binary-search-tree · binary-tree · breadth-first-search · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

May ¹¹

Sort a Linked List

May 29, 2023 · 1 min · divide-and-conquer · leetcode · linked-list · merge-sort · sorting · two-pointers · Last updated: Aug 2, 2025

Find ceiling of target element in a sorted array

May 29, 2023 · 2 min · divide-n-conquer · search · sorted-array · search/binary · floor · ceiling · Last updated: Aug 2, 2025

Merge Sort Algorithm

May 25, 2023 · 7 min · divide-n-conquer · sorting · merge-sort · video · Last updated: Aug 2, 2025

Find increasing triplet subsequence

May 25, 2023 · 7 min · greedy · subsequence · Last updated: Oct 4, 2024

Dutch National Flag DNF

May 24, 2023 · 6 min · 2sum · array · binary-array · color · daily-coding-problem · dutch · leetcode · n-sum · partition · quicksort · sorting · sum · two-pointers · video · Last updated: Aug 2, 2025

Longest Increasing Subsequence

May 23, 2023 · 15 min · array · binary-search · daily-coding-problem · dynamic-programming · leetcode · lis-longest-increasing-subsequence · longest · video · Last updated: Aug 15, 2025

Bipartite Graph Definition

May 22, 2023 · 2 min · Last updated: Aug 2, 2025

Count Number of Leaf Nodes in Binary Tree

May 21, 2023 · 1 min · bt-binary-tree · count · binary-tree-leaf · Last updated: Aug 2, 2025

Breadth First Search

May 12, 2023 · 4 min · graph · traversal · video · Last updated: Aug 2, 2025

Kth Smallest Element Using Randomized Selection

May 5, 2023 · 3 min · array · array-algo · k-smallest-largest · quickselect · kth · randomized-algo · Last updated: Aug 2, 2025

Sliding Window Maximum

May 5, 2023 · 11 min · array · daily-coding-problem · heap-priority-queue · heap/max · leetcode · monotonic-queue · queue · queue/monotonic · sliding-window · Last updated: Aug 2, 2025

April ¹³⁶

Convert an infix expression to postfix

April 30, 2023 · 6 min · conversion · stack · rpn · infix · Last updated: Aug 2, 2025

Longest Common Substring

April 30, 2023 · 5 min · string-algo · dynamic-programming · longest · substring · Last updated: Aug 2, 2025

Morris-Pratt String Searching

April 30, 2023 · 5 min · string · string-algo · Last updated: Aug 2, 2025

Unique BSTs 1 - Count

April 30, 2023 · 5 min · binary-search-tree · binary-tree · bst-binary-search-tree · count · dynamic-programming · interviewbit · leetcode · math · permutation-combination · tree · Last updated: Nov 4, 2024

Perfect number

April 29, 2023 · 2 min · leetcode · math · maths · numerical-algo · Last updated: Jul 31, 2025

Boolean Parenthesization Problem

April 29, 2023 · 9 min · dynamic-programming · daily-coding-problem · max-min · Last updated: Aug 10, 2025

Check if Array Contains All Elements Of Some Given Range

April 29, 2023 · 3 min · duplicates-algo · array · array-algo · Last updated: Aug 2, 2025

Container With Most Water

April 29, 2023 · 3 min · array · greedy · interviewbit · leetcode · stock-algo · tower · two-pointers · video · Last updated: Aug 2, 2025

Count Complete Tree Nodes

April 29, 2023 · 6 min · binary-search · binary-tree · bit-manipulation · bt-binary-tree · complete-binary-tree · count · daily-coding-problem · leetcode · tree · Last updated: Aug 2, 2025

Counting Bits

April 29, 2023 · 9 min · bit-manipulation · bits · count · dynamic-programming · leetcode · video · Last updated: Aug 10, 2025

Find GCD of two numbers

April 29, 2023 · 1 min · numerical-algo · Last updated: Jul 31, 2025

Jump Game 1 - Check if it reaches last index

April 29, 2023 · 10 min · array · dynamic-programming · game-development · greedy · leetcode · video · Last updated: Aug 2, 2025

Longest Common Subsequence LCS 1 - Get Length

April 29, 2023 · 9 min · array · binary-tree · depth-first-search · dynamic-programming · greedy · leetcode · longest · recursion · string · string-algo · subsequence · tree · video · Last updated: Aug 2, 2025

Longest Common Subsequence LCS 2 - Get Subsequence

April 29, 2023 · 3 min · subsequence · string · dynamic-programming · Last updated: Aug 2, 2025

Lowest Common Ancestor of a Binary Tree

April 29, 2023 · 6 min · backtracking · binary-tree · bt-binary-tree · depth-first-search · euler · graph · leetcode · lowest · rmq-range-minimum-query · traversal/postorder · tree · video · Last updated: Mar 4, 2025

Pascal’s Triangle 1 - Generate first n rows

April 29, 2023 · 4 min · array · dynamic-programming · leetcode · numerical-algo · pascal · triangle · Last updated: Aug 2, 2025

Rearrange positive and negative numbers in an array without changing their order

April 29, 2023 · 7 min · duplicates-algo · array · array-algo · rearrange-array · Last updated: Aug 2, 2025

Search in a Binary Search Tree

April 29, 2023 · 4 min · binary-search-tree · binary-tree · bst-binary-search-tree · leetcode · search · tree · Last updated: Aug 2, 2025

Sieve of Eratosthenes Algorithm

April 29, 2023 · 6 min · numerical-algo · Last updated: Aug 6, 2025

Skyline Problem

April 29, 2023 · 5 min · array · binary-indexed-tree · bt-binary-tree · divide-and-conquer · heap-priority-queue · interval · leetcode · line-sweep · ordered-set · segment-tree · Last updated: Aug 9, 2025

Split Linked List in alternating way

April 29, 2023 · 2 min · linkedlist · split · alternate · Last updated: Aug 2, 2025

Stock Span

April 29, 2023 · 6 min · stock-algo · Last updated: Aug 2, 2025

Tower of Hanoi

April 29, 2023 · 7 min · ctci · stack · recursion · puzzle · video · Last updated: Aug 2, 2025

Transpose of a Matrix

April 29, 2023 · 3 min · array · leetcode · linear-algebra · matrix · simulation · Last updated: Jun 25, 2024

Unique Paths in Grid - Count all paths moving right or down or diagonally

April 29, 2023 · 4 min · matrix · dynamic-programming · path-finding · count · Last updated: Aug 2, 2025

Unique Paths in Grid 2-2 - Get all paths moving right or down with obstacles

April 29, 2023 · 4 min · backtracking · path-finding · maze · Last updated: Jun 17, 2024

Unique Paths in Grid 2-3 - Get all paths moving in 4 directions with obstacles

April 29, 2023 · 4 min · backtracking · maze · path-finding · Last updated: Aug 2, 2025

Word Ladder 1 - Get Ladder Length

April 29, 2023 · 4 min · bfs · breadth-first-search · graph · hash-table · leetcode · search · string · word · Last updated: Aug 2, 2025

Binary Tree Inorder Traversal

April 29, 2023 · 3 min · binary-tree · bt-binary-tree · cleanup · depth-first-search · interviewbit · leetcode · stack · traversal · tree · Last updated: Jul 22, 2025

Binary Tree Postorder Traversal

April 29, 2023 · 6 min · binary-tree · bt-binary-tree · depth-first-search · interviewbit · leetcode · stack · traversal · traversal/postorder · tree · Last updated: Aug 2, 2025

Binary Tree Top View

April 29, 2023 · 3 min · views · bst-binary-search-tree · bt-binary-tree · traversal · traversal/level-order · Last updated: Aug 2, 2025

Count Univalue Subtrees

April 29, 2023 · 4 min · binary-tree · bt-binary-tree · count · daily-coding-problem · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Generate Parentheses

April 29, 2023 · 9 min · backtracking · catalan-numbers · ctci · dynamic-programming · interviewbit · leetcode · parentheses · permutation-combination · recursion · string · traversal/level-order · Last updated: Aug 2, 2025

Inorder Successor in Binary Search Tree

April 29, 2023 · 4 min · binary-search-tree · binary-tree · bst-binary-search-tree · depth-first-search · iterator · leetcode · pramp · successor · traversal/inorder · tree · Last updated: Aug 2, 2025

Inorder Successor in Binary Search Tree Using Parent link

April 29, 2023 · 3 min · binary-search-tree · binary-tree · ctci · daily-coding-problem · leetcode · parent · traversal/inorder · tree · Last updated: Aug 2, 2025

Unique Paths in Grid 1 - Count all paths moving right or down

April 29, 2023 · 11 min · combinatorics · count · ctci · daily-coding-problem · dynamic-programming · leetcode · math · maths · matrix · path-finding · recursion · video · Last updated: Aug 2, 2025

Valid Parentheses

April 29, 2023 · 2 min · daily-coding-problem · duplicates-algo · leetcode · parentheses · stack · string · video · Last updated: Aug 2, 2025

What happens when you type an URL in the browser and press enter

April 29, 2023 · 4 min · ctci · interview-question · network · daily-coding-problem · Last updated: Jan 22, 2025

Kth largest element in Binary Search Tree

April 27, 2023 · 2 min · bst-binary-search-tree · ranking · k-largest-largest · kth · traversal/inorder · reverse-inorder · Last updated: Aug 2, 2025

Longest Palindromic Subsequence 1 - Get Length

April 27, 2023 · 14 min · dynamic-programming · leetcode · longest · matrix · palindrome · recursion · string · string-algo · subsequence · Last updated: Aug 11, 2025

Last Stone Weight

April 24, 2023 · 2 min · array · heap · heap-priority-queue · heap/max · leetcode · Last updated: Aug 2, 2025

Maximum Width of Binary Tree

April 20, 2023 · 4 min · binary-tree · breadth-first-search · depth-first-search · leetcode · traversal/level-order · tree · Last updated: Aug 2, 2025

Cousins in Binary Tree 2

April 15, 2023 · 7 min · bfs · binary-tree · breadth-first-search · bt-binary-tree · depth-first-search · hash-table · leetcode · tree · video · Last updated: Aug 2, 2025

Cousins in Binary Tree

April 15, 2023 · 5 min · bfs · binary-tree · breadth-first-search · bt-binary-tree · depth-first-search · dfs · leetcode · todo · tree · Last updated: Aug 9, 2025

Cousins in Tree Definition

April 15, 2023 · 1 min · Last updated: Aug 2, 2025

Good vs Bad Hash function examples

April 15, 2023 · 6 min · hash-table · Last updated: Aug 2, 2025

Implement queue using deque

April 15, 2023 · 3 min · stack · queue · Last updated: Aug 2, 2025

Implement stack using deque

April 15, 2023 · 3 min · stack · queue · Last updated: Aug 2, 2025

Implement stack using priority queue

April 15, 2023 · 4 min · stack · queue/priority · daily-coding-problem · Last updated: Aug 2, 2025

Design a vending machine like coffee vending machine

April 14, 2023 · 2 min · ood-object-oriented-design · Last updated: May 19, 2024

Autocomplete Suggestion System

April 14, 2023 · 3 min · auto-complete · autosuggest · bfs · daily-coding-problem · dfs · tree-ds · trie · Last updated: Aug 2, 2025

Balanced delimiters in an expression

April 14, 2023 · 3 min · parentheses · Last updated: Aug 2, 2025

Catalan Numbers

April 14, 2023 · 3 min · dynamic-programming · catalan-numbers · Last updated: Aug 2, 2025

Climbing Stairs - Take atmost 2 Steps

April 14, 2023 · 11 min · daily-coding-problem · dynamic-programming · leetcode · math · memoization · video · Last updated: Aug 2, 2025

Clone Undirected Graph

April 14, 2023 · 5 min · breadth-first-search · depth-first-search · graph · hash-table · leetcode · Last updated: Aug 2, 2025

Construct Binary Tree from Inorder and Level Order Traversal

April 14, 2023 · 3 min · bt-binary-tree · traversal · Last updated: Aug 2, 2025

Convert Sorted Array to height-balanced Binary Search Tree

April 14, 2023 · 2 min · array · array-algo · balanced-bst · binary-search-tree · binary-tree · bst-binary-search-tree · convert · ctci · divide-and-conquer · leetcode · sorted-array · traversal/preorder · tree · tree-ds · video · Last updated: Aug 2, 2025

Copy List with Random Pointer

April 14, 2023 · 4 min · hash-table · leetcode · linked-list · linkedlist · Last updated: Aug 2, 2025

Delete X Nodes After Y Nodes

April 14, 2023 · 3 min · linkedlist · Last updated: Aug 2, 2025

Evaluation of Arithmetic Expression Tree

April 14, 2023 · 3 min · bt-binary-tree · daily-coding-problem · expression-tree · traversal/postorder · Last updated: Aug 2, 2025

Flatten a Multi-Level Linked List level by level

April 14, 2023 · 4 min · linkedlist · Last updated: Aug 2, 2025

Intersection of Two Linked Lists

April 14, 2023 · 10 min · daily-coding-problem · hash-table · intersection · leetcode · linked-list · linkedlist · two-pointers · Last updated: Aug 2, 2025

K reverse a Linked List in alternating way

April 14, 2023 · 4 min · linkedlist · reverse · alternate · Last updated: Aug 2, 2025

Lowest Common Ancestor of a Binary Search Tree

April 14, 2023 · 5 min · binary-search-tree · binary-tree · bst-binary-search-tree · depth-first-search · leetcode · lowest · tree · video · Last updated: Aug 2, 2025

Maximal Square

April 14, 2023 · 6 min · array · binary-array · binary-matrix · dynamic-programming · leetcode · matrix · max-min · square-matrix · Last updated: Aug 2, 2025

Minimum Path Sum in matrix

April 14, 2023 · 8 min · array · binary-tree-path · dynamic-programming · leetcode · matrix · path-finding · pathsum · sum · Last updated: Jul 27, 2025

Minimum Window Substring

April 14, 2023 · 6 min · hash-table · interviewbit · leetcode · max-min · sliding-window · string · string-algo · subarray · substring · window · Last updated: Aug 12, 2025

N-Queens

April 14, 2023 · 7 min · array · backtracking · ctci · daily-coding-problem · leetcode · path-finding · sudoku · Last updated: Aug 2, 2025

Print All Combinations of subset of size K from Given Array

April 14, 2023 · 2 min · permutation-combination · subset · backtracking · Last updated: Aug 2, 2025

Print binary representation of a decimal number

April 14, 2023 · 4 min · ctci · bits · Last updated: Aug 2, 2025

Rabin-Karp Algorithm Explained

April 14, 2023 · 9 min · string · todo · hashing · string-algo · pattern-matching · rolling-hash · hashing/rolling · Last updated: Aug 2, 2025

Rearrange array elements - first and second half in alternating order

April 14, 2023 · 6 min · divide-n-conquer · rearrange-array · alternate · incomplete · Last updated: Aug 2, 2025

Rearrange array to match each index with element value

April 14, 2023 · 3 min · duplicates-algo · array · array-algo · ranged-array · rearrange-array · incomplete · Last updated: Jan 2, 2025

Return all diagonals of a rectangular two-dimensional matrix

April 14, 2023 · 7 min · array · matrix · array-algo · backtracking · Last updated: Aug 2, 2025

Reverse a Doubly Linked List

April 14, 2023 · 2 min · linkedlist · reverse · doubly-linked-list · Last updated: Aug 2, 2025

Swap Every Kth Node in a LinkedList

April 14, 2023 · 4 min · linkedlist · swap · Last updated: Aug 2, 2025

Unique Paths in Grid 1-2 - Get all paths moving right or down

April 14, 2023 · 3 min · array · array-algo · backtracking · path-finding · recursion · robot · Last updated: Aug 2, 2025

Binary Tree Left Side View

April 14, 2023 · 2 min · views · bt-binary-tree · traversal · Last updated: Aug 2, 2025

Binary Tree Right Side View

April 14, 2023 · 3 min · binary-tree · breadth-first-search · bt-binary-tree · depth-first-search · leetcode · traversal · tree · views · Last updated: Aug 2, 2025

Create linked lists of all the nodes at each depth for a Binary Tree

April 14, 2023 · 3 min · ctci · linkedlist · bt-binary-tree · traversal/level-order · Last updated: Aug 2, 2025

Diameter Of a Binary Tree

April 14, 2023 · 4 min · binary-tree · bt-binary-tree · depth-first-search · interviewbit · leetcode · tree · Last updated: Aug 2, 2025

Floyd Cycle-Finding Algorithm

April 14, 2023 · 4 min · named-algo-ds/algo · cycle · cycle-detection · linkedlist · Last updated: Aug 2, 2025

K Reverse a linked list

April 14, 2023 · 5 min · leetcode · linked-list · linkedlist · recursion · reverse · Last updated: Aug 2, 2025

Linked List Cycle 1 - Detect Cycle

April 14, 2023 · 3 min · cycle · hash-table · interviewbit · leetcode · linked-list · linkedlist · two-pointers · video · Last updated: Aug 2, 2025

Maximum Depth of Binary Tree

April 14, 2023 · 3 min · bfs · binary-tree · breadth-first-search · bt-binary-tree · depth-first-search · dfs · leetcode · max-min · traversal/inorder · traversal/postorder · traversal/preorder · tree · Last updated: Aug 2, 2025

Populate next pointer to right node in Perfect Binary Tree

April 14, 2023 · 2 min · binary-tree · breadth-first-search · bt-binary-tree · depth-first-search · leetcode · linked-list · tree · Last updated: Aug 2, 2025

Same Tree

April 14, 2023 · 5 min · binary-tree · breadth-first-search · bt-binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 17, 2025

Search a 2D Matrix 2 - Rows and columns are sorted

April 14, 2023 · 15 min · array · binary-search · ctci · divide-and-conquer · leetcode · matrix · sorted-array · sorted-matrix · sorting · Last updated: Aug 1, 2025

Sum of Left Leaves

April 14, 2023 · 1 min · binary-tree · binary-tree-leaf · breadth-first-search · bt-binary-tree · depth-first-search · leetcode · tree · video · Last updated: Aug 2, 2025

Validate Stack Sequences

April 13, 2023 · 2 min · array · leetcode · simulation · stack · Last updated: Aug 2, 2025

Binary Tree Preorder Traversal

April 9, 2023 · 3 min · binary-tree · depth-first-search · leetcode · stack · traversal · tree · Last updated: Aug 2, 2025

Allocate Mailboxes

April 8, 2023 · 6 min · array · counting · database · dynamic-programming · greedy · hash-table · incomplete · leetcode · math · prefix-sum · sorting · Last updated: Aug 2, 2025

Stone Game 1

April 8, 2023 · 3 min · array · dynamic-programming · game-theory · leetcode · math · Last updated: Aug 2, 2025

Arithmetic Slices

April 8, 2023 · 4 min · array · dynamic-programming · incomplete · leetcode · sliding-window · Last updated: Aug 2, 2025

Build Array Where You Can Find The Maximum Exactly K Comparisons

April 8, 2023 · 7 min · database · dynamic-programming · incomplete · leetcode · prefix-sum · string · Last updated: Aug 2, 2025

Champagne Tower

April 8, 2023 · 5 min · dynamic-programming · incomplete · leetcode · Last updated: Aug 2, 2025

Paint House 3

April 8, 2023 · 18 min · array · binary-search · design · dynamic-programming · hash-table · leetcode · linked-list · matrix · monotonic-stack · sliding-window · stack · Last updated: Aug 2, 2025

Best Time To Buy And Sell Stock 4 - at most k times

April 8, 2023 · 12 min · array · dynamic-programming · leetcode · max-min · state-machine · stock-algo · Last updated: Aug 2, 2025

Count All Possible Routes

April 8, 2023 · 11 min · array · dynamic-programming · hash-table · leetcode · math · memoization · string · two-pointers · Last updated: Aug 2, 2025

Freedom Trail

April 8, 2023 · 4 min · breadth-first-search · depth-first-search · dynamic-programming · incomplete · leetcode · string · Last updated: Aug 2, 2025

Longest Arithmetic Subsequence

April 8, 2023 · 5 min · array · binary-search · binary-tree · depth-first-search · dynamic-programming · hash-table · hashing · leetcode · search/binary · string · tree · Last updated: Aug 2, 2025

Maximum Length of Repeated Subarray

April 8, 2023 · 5 min · array · binary-search · dynamic-programming · hash-function · leetcode · rolling-hash · sliding-window · Last updated: Aug 11, 2025

Minimum Falling Path Sum

April 8, 2023 · 5 min · array · dynamic-programming · leetcode · matrix · todo · Last updated: Aug 2, 2025

Minimum Falling Path Sum II

April 8, 2023 · 6 min · array · binary-search · dynamic-programming · enumeration · leetcode · linked-list · math · matrix · prefix-sum · Last updated: Aug 2, 2025

Minimum Number of Refueling Stops

April 8, 2023 · 5 min · array · dynamic-programming · greedy · heap-priority-queue · leetcode · Last updated: Aug 2, 2025

Number of Submatrices That Sum to Target

April 8, 2023 · 5 min · array · database · hash-table · leetcode · matrix · prefix-sum · string · Last updated: Aug 2, 2025

Number of Ways of Cutting a Pizza

April 8, 2023 · 10 min · array · database · dynamic-programming · leetcode · matrix · memoization · Last updated: Aug 2, 2025

Number of Ways to Paint N × 3 Grid

April 8, 2023 · 4 min · array · backtracking · database · dynamic-programming · greedy · leetcode · math · prefix-sum · string · todo · Last updated: Aug 2, 2025

Out of Boundary Paths

April 8, 2023 · 7 min · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Stone Game 2

April 8, 2023 · 6 min · array · database · dynamic-programming · game-theory · leetcode · math · prefix-sum · video · Last updated: Aug 2, 2025

Where Will the Ball Fall

April 8, 2023 · 6 min · array · bit-manipulation · database · dynamic-programming · greedy · leetcode · matrix · simulation · sorting · todo · trie · Last updated: Aug 2, 2025

Bitwise ORs of Subarrays

April 8, 2023 · 4 min · array · bit-manipulation · dynamic-programming · incomplete · leetcode · Last updated: Aug 2, 2025

Generate nth ugly number

April 8, 2023 · 9 min · dynamic-programming · hash-table · heap · heap-priority-queue · leetcode · math · primality · todo · Last updated: Aug 9, 2025

Can I Win

April 8, 2023 · 6 min · bit-manipulation · bitmask · dynamic-programming · game-theory · leetcode · math · memoization · Last updated: Aug 2, 2025

Maximum Number of Achievable Transfer Requests

April 8, 2023 · 6 min · array · backtracking · binary-tree · bit-manipulation · breadth-first-search · counting · design · enumeration · hash-table · leetcode · simulation · sorting · string · tree · Last updated: Aug 2, 2025

Ones and Zeroes

April 8, 2023 · 5 min · array · dynamic-programming · leetcode · string · Last updated: Aug 2, 2025

Profitable Schemes

April 8, 2023 · 7 min · array · dynamic-programming · leetcode · todo · Last updated: Aug 2, 2025

Reducing Dishes

April 8, 2023 · 4 min · array · dynamic-programming · greedy · leetcode · sorting · todo · Last updated: Aug 2, 2025

House Robber 2 - Houses in circle

April 8, 2023 · 7 min · array · dynamic-programming · leetcode · video · Last updated: Aug 2, 2025

Palindrome Partitioning

April 8, 2023 · 3 min · backtracking · dfs · dynamic-programming · leetcode · palindrome · partition · string · video · Last updated: Aug 2, 2025

Concatenated Words

April 8, 2023 · 11 min · array · depth-first-search · dynamic-programming · leetcode · string · todo · trie · Last updated: Aug 2, 2025

Maximum Profit in Job Scheduling

April 8, 2023 · 6 min · array · backtracking · binary-search · bit-manipulation · breadth-first-search · depth-first-search · dynamic-programming · interactive · interval · leetcode · math · schedule · sorting · string · two-pointers · Last updated: Aug 2, 2025

Number of Ways to Form a Target String Given a Dictionary

April 8, 2023 · 8 min · array · dynamic-programming · hash-table · leetcode · string · todo · Last updated: Aug 2, 2025

Number of Ways to Reorder Array to Get Same BST

April 8, 2023 · 7 min · array · binary-search-tree · binary-tree · combinatorics · database · design · divide-and-conquer · dynamic-programming · hash-table · leetcode · math · matrix · memoization · string · todo · tree · two-pointers · union-find · Last updated: Aug 2, 2025

Decode Ways II

April 8, 2023 · 9 min · dynamic-programming · leetcode · string · Last updated: Aug 2, 2025

Minimum Cost For Tickets

April 8, 2023 · 16 min · array · dynamic-programming · greedy · leetcode · string · todo · Last updated: Aug 2, 2025

Find duplicate elements in the array with 4KB memory only

April 7, 2023 · 2 min · ctci · system-design-question · system-design · Last updated: May 4, 2024

Design a data structure for generic deck of cards

April 7, 2023 · 4 min · ctci · ood-object-oriented-design · Last updated: Aug 1, 2024

Design data structures for an online book reader system

April 7, 2023 · 4 min · ctci · ood-object-oriented-design · Last updated: May 16, 2024

Design the classes and data structures for a call center

April 7, 2023 · 4 min · ctci · ood-object-oriented-design · Last updated: Aug 2, 2024

Boats to Save People

April 3, 2023 · 2 min · 2sum · array · greedy · leetcode · sorting · two-pointers · video · Last updated: Aug 9, 2025

Find Second largest element in an array

April 2, 2023 · 2 min · array · array-algo · largest · Last updated: Aug 2, 2025

Find duplicate number in array containing n+1 numbers between 1 and n

April 2, 2023 · 5 min · array · array-1-n · array-algo · binary-search · bit-manipulation · cycle-detection · daily-coding-problem · duplicates-algo · leetcode · linkedlist · ranged-array · repeat · todo · two-pointers · xor · Last updated: Jan 2, 2025

Kadane’s Algorithm for Maximum Subarray Sum

April 1, 2023 · 3 min · named-algo-ds/algo · kadane · sum · subarray · max-min · subarray-sum · sliding-window · video · Last updated: Aug 2, 2025

Longest Valid Parentheses

April 1, 2023 · 17 min · dynamic-programming · kadane · leetcode · longest · parentheses · stack · string · todo · Last updated: Aug 2, 2025

Candy distribution

April 1, 2023 · 4 min · array · greedy · interviewbit · leetcode · tower · Last updated: Aug 8, 2025

March ¹³²

Binary Tree DFS Traversal

March 31, 2023 · 1 min · bt-binary-tree · traversal · Last updated: Jul 23, 2025

Binary Tree Level Order Traversal

March 31, 2023 · 3 min · bt-binary-tree · daily-coding-problem · leetcode · traversal · traversal/level-order · video · Last updated: Aug 2, 2025

Binary Tree Level Order Traversal - Level by Level

March 31, 2023 · 5 min · binary-tree · breadth-first-search · bt-binary-tree · leetcode · traversal/level-order · tree · video · Last updated: Aug 2, 2025

Find Deepest Node in a Binary Tree

March 31, 2023 · 2 min · bt-binary-tree · daily-coding-problem · Last updated: Aug 2, 2025

XOR doubly linked list

March 31, 2023 · 7 min · xor · doubly-linked-list · daily-coding-problem · linkedlist · Last updated: Aug 2, 2025

Binary Search on a linked list

March 31, 2023 · 4 min · divide-n-conquer · search · linkedlist · sorted-array · search/binary · Last updated: Aug 2, 2025

Merge Two Sorted Linked Lists

March 31, 2023 · 4 min · leetcode · linked-list · linkedlist · merge-sort · recursion · sorted-list · video · Last updated: Aug 2, 2025

Stack of plates

March 31, 2023 · 11 min · ctci · stack · data-structure · design · array · Last updated: Aug 7, 2025

Evaluate Reverse Polish Notation

March 31, 2023 · 4 min · array · leetcode · math · rpn · stack · Last updated: Aug 2, 2025

Linked List Cycle 3 - Find length of cycle

March 31, 2023 · 2 min · linkedlist · Last updated: Aug 2, 2025

Reverse Words in a String

March 31, 2023 · 3 min · leetcode · reverse · string · two-pointers · Last updated: Aug 2, 2025

Longest Palindromic Substring

March 31, 2023 · 10 min · daily-coding-problem · dynamic-programming · interviewbit · leetcode · longest · palindrome · string · string-algo · substring · two-pointers · video · Last updated: Jul 14, 2025

Subsets 1

March 31, 2023 · 4 min · array · array-algo · backtracking · bit-manipulation · bits · ctci · daily-coding-problem · dynamic-programming · leetcode · permutation-combination · subset · video · Last updated: Aug 2, 2025

Is Subsequence

March 31, 2023 · 4 min · dynamic-programming · leetcode · string · subsequence · two-pointers · video · Last updated: Aug 2, 2025

Maximum Number of Removable Characters Problem

March 31, 2023 · 5 min · array · binary-search · leetcode · string · two-pointers · Last updated: Nov 5, 2024

Subarrays vs Subsequences vs Subsets Definition

March 31, 2023 · 1 min · subset · subarray · subsequence · todo · video · Last updated: Aug 2, 2025

Convert String to Integer atoi

March 31, 2023 · 4 min · algorithm · atoi · conversion · convert · integer · interviewbit · java · leetcode · string · string-algo · udf · Last updated: Aug 2, 2025

Check if a Matrix is Invertible

March 31, 2023 · 5 min · Last updated: Aug 2, 2025

Print all subarrays of a given array

March 31, 2023 · 2 min · recursion · subarray · Last updated: Aug 2, 2025

Sum of all subarrays

March 31, 2023 · 5 min · sum · subarray · Last updated: Aug 2, 2025

Finding the most frequent element in an array of numbers from 0 to n-1

March 31, 2023 · 6 min · repeat · duplicates-algo · array-algo · array-1-n · ranged-array · incomplete · Last updated: Aug 2, 2025

Find first duplicate number in an array containing numbers from 1 to n

March 31, 2023 · 6 min · repeat · duplicates-algo · array-algo · array-1-n · ranged-array · Last updated: Aug 2, 2025

Find duplicates in an array of integers within range 0 to n-1

March 31, 2023 · 3 min · repeat · duplicates-algo · ranged-array · consecutive · absolute · array-1-n · array-algo · Last updated: Jan 2, 2025

Majority Element 2 - With n by 3 definition

March 31, 2023 · 4 min · array · counting · duplicates-algo · hash-table · leetcode · repeat · sorting · Last updated: Aug 2, 2025

Majority Element 1 - with n by 2 definition

March 31, 2023 · 3 min · repeat · duplicates-algo · leetcode · named-algo-ds/algo · interviewbit · greedy · Last updated: Aug 2, 2025

Check if Array is Consecutive Integers

March 31, 2023 · 3 min · duplicates-algo · array · array-algo · ranged-array · consecutive · Last updated: Aug 2, 2025

Check if Array is Consecutive Positive Integers

March 31, 2023 · 3 min · duplicates-algo · array · array-algo · ranged-array · consecutive · Last updated: Aug 2, 2025

Contains Duplicate 1 - Check if array has duplicates

March 31, 2023 · 3 min · array · count · duplicates-algo · hash-table · hashing · leetcode · sorting · video · Last updated: Aug 2, 2025

Find element which appears maximum number of times in the ranged array

March 31, 2023 · 2 min · duplicates-algo · ranged-array · frequency · Last updated: Jan 2, 2025

Find most frequent element in the array

March 31, 2023 · 4 min · duplicates-algo · repeat · array-algo · frequency · Last updated: Aug 2, 2025

Find local minima in a given array

March 31, 2023 · 4 min · divide-n-conquer · local-minima-maxima · Last updated: Aug 2, 2025

Find local minimum or maximum in O(1) time in an array with elements differing by plus minus 1

March 31, 2023 · 4 min · array · array-algo · local-minima-maxima · Last updated: Aug 2, 2025

Find the smallest integer that cannot be represented as sum of any subset of sorted array

March 31, 2023 · 3 min · array · array-algo · subset · Last updated: Aug 2, 2025

Count the number of elements from one array less than or equal to elements in another array

March 31, 2023 · 3 min · array · Last updated: Aug 2, 2025

Find duplicates in a given array

March 31, 2023 · 4 min · repeat · duplicates-algo · absolute · Last updated: Aug 2, 2025

Kth Smallest Element in a BST

March 31, 2023 · 2 min · binary-search-tree · binary-tree · bst-binary-search-tree · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

Kth smallest absolute difference in array

March 31, 2023 · 3 min · array · array-algo · k-smallest-largest · kth · arithmetic-difference · Last updated: Aug 2, 2025

Median of Two Sorted Arrays

March 31, 2023 · 5 min · array · binary-search · divide-and-conquer · divide-n-conquer · interviewbit · k-sorted · leetcode · median · sorted-array · Last updated: Mar 4, 2025

Kth Largest Element Using Randomized Selection

March 31, 2023 · 2 min · leetcode · Last updated: May 5, 2024

Finding the Maximum Distance Between Increasing Elements in an Array

March 31, 2023 · 5 min · duplicates-algo · array · array-algo · Last updated: Jan 2, 2025

Count Occurrences of Anagram

March 31, 2023 · 4 min · anagram · sliding-window · Last updated: Aug 2, 2025

Subtree of Another Tree

March 31, 2023 · 4 min · binary-tree · blind75 · bt-binary-tree · ctci · daily-coding-problem · depth-first-search · hash-function · leetcode · string-matching · tree · Last updated: Aug 2, 2025

Longest Common Prefix in array of string

March 31, 2023 · 2 min · array · array-algo · leetcode · longest · prefix · string · trie · Last updated: Aug 2, 2025

Find rotation count in rotated sorted array

March 31, 2023 · 2 min · rotate · rotated-array · rotated-sorted-array · Last updated: Aug 2, 2025

Find Minimum in Rotated Sorted Array

March 31, 2023 · 5 min · array · binary-search · daily-coding-problem · leetcode · max-min · rotate · rotated-array · rotated-sorted-array · search/binary · video · Last updated: Aug 2, 2025

Set Matrix Zeros

March 31, 2023 · 18 min · array · binary-array · ctci · hash-table · interviewbit · leetcode · matrix · video · Last updated: Aug 2, 2025

Find duplicate number in array with 1 to N+1 numbers with one number repeating

March 31, 2023 · 1 min · repeat · duplicates-algo · array-algo · array-1-n · ranged-array · Last updated: Aug 2, 2025

Linked List Cycle 2 - Find Start of a Cycle

March 31, 2023 · 2 min · ctci · cycle · hash-table · interviewbit · leetcode · linked-list · linkedlist · two-pointers · Last updated: Aug 2, 2025

Maximal Rectangle

March 31, 2023 · 10 min · array · binary-array · binary-matrix · daily-coding-problem · dynamic-programming · interviewbit · leetcode · matrix · max-min · monotonic-stack · queue/deque · rectangle · stack · Last updated: Jan 8, 2025

Coin Change with Fewest Number of Coins Given Infinite Supply

March 31, 2023 · 18 min · array · breadth-first-search · coin · dynamic-programming · leetcode · max-min · video · Last updated: Aug 11, 2025

Finding the Critical Point in a Mountain or Valley-Shaped Array

March 31, 2023 · 3 min · array · array-algo · bitonic · todo · Last updated: Aug 2, 2025

Find the smallest subarray with a sum greater than a given integer

March 31, 2023 · 4 min · array · array-algo · sum · subarray · max-min · sliding-window · Last updated: Aug 2, 2025

Rearrange array to alternate positive and negative elements

March 31, 2023 · 4 min · duplicates-algo · array · array-algo · rearrange-array · alternate · partition · Last updated: Aug 2, 2025

Subarray sum equals K - Return any subarray

March 31, 2023 · 3 min · array · array-algo · daily-coding-problem · sliding-window · subarray · subarray-sum · sum · Last updated: Aug 2, 2025

Sort an array

March 31, 2023 · 1 min · array · bucket-sort · counting-sort · divide-and-conquer · heap-priority-queue · leetcode · merge-sort · radix-sort · sorting · video · Last updated: Aug 2, 2025

Binary Search on Sorted Array

March 31, 2023 · 7 min · array · binary-search · divide-n-conquer · leetcode · search · search/binary · sorted-array · todo · video · Last updated: Aug 2, 2025

Insertion Sort

March 31, 2023 · 3 min · insertion-sort · Last updated: Aug 2, 2025

Word Squares

March 31, 2023 · 9 min · array · backtracking · leetcode · string · trie · Last updated: Aug 2, 2025

House Robber

March 30, 2023 · 10 min · array · daily-coding-problem · dynamic-programming · leetcode · video · Last updated: Aug 2, 2025

Flood Fill

March 30, 2023 · 4 min · array · backtracking · breadth-first-search · color · ctci · daily-coding-problem · depth-first-search · dfs · leetcode · matrix · recursion · Last updated: Aug 2, 2025

3 bags of 2 marbles

March 28, 2023 · 2 min · Last updated: Aug 2, 2025

Merge Sort in a Linked list

March 27, 2023 · 3 min · sorting · linkedlist · merge-sort · leetcode · Last updated: Aug 2, 2025

Longest Cycle in a Directed Graph

March 26, 2023 · 6 min · array · counting · database · depth-first-search · dynamic-programming · graph · greedy · hash-table · leetcode · math · ordered-set · simulation · sorting · topological-sort · Last updated: Jul 29, 2025

3Sum0 - Find three elements in an array that sum to a zero

March 24, 2023 · 8 min · 2sum · array · leetcode · n-sum · sorting · sum · two-pointers · video · Last updated: Aug 2, 2025

3Sum - Classic

March 24, 2023 · 4 min · sum · n-sum · 2sum · two-pointers · Last updated: Aug 10, 2025

Two Sum

March 24, 2023 · 8 min · 2sum · array · array-algo · daily-coding-problem · hash-table · leetcode · n-sum · pair_tuple · sum · video · Last updated: Aug 2, 2025

Meeting Rooms 2 - Minimum Meeting Rooms Required

March 24, 2023 · 1 min · array · bt-binary-tree · daily-coding-problem · greedy · heap-priority-queue · interval · leetcode · prefix-sum · sorting · two-pointers · Last updated: Aug 2, 2025

Meeting Rooms 1 - Can person attend all meetings

March 24, 2023 · 1 min · array · interval · leetcode · sorting · Last updated: Mar 4, 2025

Maximum Product Subarray

March 24, 2023 · 7 min · array · dynamic-programming · kadane · leetcode · max-min · product · subarray · video · Last updated: Aug 2, 2025

Middle of the linked list

March 24, 2023 · 4 min · interviewbit · leetcode · linked-list · linkedlist · two-pointers · video · Last updated: Aug 2, 2025

Next Permutation

March 24, 2023 · 8 min · array · daily-coding-problem · leetcode · permutation-combination · todo · two-pointers · Last updated: Aug 2, 2025

Graph Valid Tree

March 23, 2023 · 5 min · breadth-first-search · bt-binary-tree · depth-first-search · graph · leetcode · union-find · Last updated: Aug 2, 2025

Find anagrams of a string in another string

March 22, 2023 · 4 min · anagram · hash-table · hashing · leetcode · sliding-window · string · string-algo · Last updated: Aug 2, 2025

Encode and Decode Strings

March 22, 2023 · 3 min · array · design · leetcode · string · Last updated: Aug 16, 2025

Triangle Judgement Problem

March 22, 2023 · 1 min · database · leetcode · sql · Last updated: Sep 26, 2024

Coin Change - Count Number of Ways of representing Amount given Infinite Supply

March 22, 2023 · 16 min · array · dynamic-programming · leetcode · Last updated: Aug 3, 2025

Best Time To Buy And Sell Stock with Transaction Fee

March 22, 2023 · 2 min · array · dynamic-programming · greedy · leetcode · stock-algo · Last updated: Aug 2, 2025

Roman numerals

March 20, 2023 · 2 min · notation · Last updated: Jul 23, 2024

Wiggle Sort 1

March 20, 2023 · 2 min · array · duplicates-algo · greedy · leetcode · rearrange-array · sorting · Last updated: Jun 3, 2025

Serialize and Deserialize Binary Search Tree BST

March 20, 2023 · 5 min · binary-search-tree · binary-tree · breadth-first-search · bst-binary-search-tree · depth-first-search · design · leetcode · serialization · string · tree · Last updated: Aug 2, 2025

Product of Array Except Self

March 20, 2023 · 7 min · array · array-algo · daily-coding-problem · leetcode · prefix-sum · product · video · Last updated: Aug 2, 2025

Implement Queue using Stacks

March 20, 2023 · 5 min · ctci · daily-coding-problem · design · leetcode · queue · stack · Last updated: Aug 2, 2025

Implement stack using queues

March 20, 2023 · 7 min · design · leetcode · queue · stack · Last updated: Aug 2, 2025

Combination Sum 3 - Find k numbers summing up to n

March 20, 2023 · 2 min · array · backtracking · leetcode · permutation-combination · Last updated: Aug 2, 2025

Implement Trie

March 20, 2023 · 4 min · design · hash-table · leetcode · string · tree-ds · trie · Last updated: Aug 2, 2025

Minimum Size Subarray Sum

March 20, 2023 · 8 min · array · binary-search · leetcode · max-min · prefix-sum · sliding-window · subarray · subarray-sum · sum · two-pointers · window · Last updated: Jan 2, 2025

Tenth Line Problem

March 20, 2023 · 2 min · leetcode · shell · Last updated: Jun 17, 2024

Transpose File Problem

March 20, 2023 · 1 min · leetcode · shell · Last updated: Nov 26, 2024

Valid Phone Numbers Problem

March 20, 2023 · 2 min · leetcode · linux-commands · regex · shell · Last updated: Jun 17, 2024

Rotate an Array to Right

March 20, 2023 · 6 min · array · leetcode · math · numerical-algo · rotate · rotated-array · todo · two-pointers · vector · Last updated: Aug 2, 2025

Repeated DNA Sequences

March 20, 2023 · 14 min · bit-manipulation · bits · hash-function · hash-table · leetcode · rolling-hash · sliding-window · string · Last updated: Aug 1, 2025

Number of Islands

March 20, 2023 · 8 min · array · bfs · breadth-first-search · daily-coding-problem · depth-first-search · dfs · disjoint-set · graph · leetcode · matrix · union-find · video · Last updated: Aug 2, 2025

Word Frequency from File

March 20, 2023 · 3 min · frequency · leetcode · shell · Last updated: Jul 30, 2025

Department Top Three Salaries Problem

March 20, 2023 · 3 min · database · leetcode · sql · Last updated: Sep 25, 2024

Consecutive Numbers Problem

March 20, 2023 · 1 min · database · leetcode · sql · Last updated: Sep 25, 2024

Combine Two Tables Problem

March 20, 2023 · 2 min · database · leetcode · sql · Last updated: Nov 26, 2024

Excel Sheet Column Title

March 20, 2023 · 3 min · excel · interviewbit · leetcode · math · string · todo · Last updated: Aug 2, 2025

Missing Ranges

March 20, 2023 · 3 min · array · leetcode · Last updated: Aug 2, 2025

Longest Substring with At Most Two Distinct Characters

March 20, 2023 · 4 min · hash-table · leetcode · sliding-window · string · Last updated: Aug 1, 2025

Read N Characters Given Read4 2 - Call Multiple Times

March 20, 2023 · 2 min · array · interactive · leetcode · simulation · string · Last updated: Aug 2, 2025

Read N Characters Given Read4

March 20, 2023 · 3 min · array · interactive · leetcode · simulation · string · Last updated: Aug 2, 2025

Find Minimum in Rotated Sorted Array 2 - Duplicates allowed

March 20, 2023 · 2 min · array · binary-search · leetcode · max-min · recursion · rotated-array · rotated-sorted-array · sorted-array · Last updated: Aug 2, 2025

Insertion Sort on List

March 20, 2023 · 2 min · interviewbit · leetcode · linked-list · linkedlist · sorting · todo · Last updated: Aug 2, 2025

Reorder List such that i-th element points to n-i-th element

March 20, 2023 · 4 min · interviewbit · leetcode · linked-list · linkedlist · recursion · stack · two-pointers · video · Last updated: Aug 2, 2025

Word Break 1 - Check if word is breakable

March 20, 2023 · 16 min · array · backtracking · bfs · dfs · dynamic-programming · hash-table · leetcode · memoization · string · trie · video · word · word-break · Last updated: Aug 2, 2025

Word Ladder 2 - Get all the ladders

March 20, 2023 · 9 min · backtracking · breadth-first-search · dfs · hash-table · leetcode · string · word · Last updated: Aug 2, 2025

Best Time To Buy And Sell Stock 3 - at most twice

March 20, 2023 · 6 min · array · dynamic-programming · leetcode · max-min · state-machine · stock-algo · Last updated: Jan 2, 2025

Best Time To Buy And Sell Stock 2 - Any number of times

March 20, 2023 · 2 min · array · dynamic-programming · greedy · interviewbit · java · leetcode · max-min · stock-algo · Last updated: Aug 2, 2025

Path Sum 2 - find all root to leaf paths

March 20, 2023 · 2 min · backtracking · binary-tree · binary-tree-path · bst-binary-search-tree · depth-first-search · dfs · interviewbit · leetcode · path-finding · pathsum · tree · Last updated: Aug 2, 2025

Binary Tree Traversal - Level Order Bottom up

March 20, 2023 · 2 min · binary-tree · breadth-first-search · bt-binary-tree · leetcode · traversal · tree · Last updated: Aug 2, 2025

Decode Ways

March 20, 2023 · 13 min · count · daily-coding-problem · dynamic-programming · leetcode · string · video · Last updated: Aug 2, 2025

Subsets 2

March 20, 2023 · 3 min · array · backtracking · bit-manipulation · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Recover Binary Search Tree

March 20, 2023 · 3 min · binary-search-tree · binary-tree · bst-binary-search-tree · depth-first-search · interviewbit · leetcode · swap · traversal/inorder · tree · Last updated: Aug 2, 2025

Edit Distance

March 20, 2023 · 5 min · daily-coding-problem · dynamic-programming · leetcode · recursion · string · Last updated: Aug 2, 2025

Simplify Path

March 20, 2023 · 4 min · leetcode · stack · string · Last updated: Aug 2, 2025

Remove duplicates from Sorted Array 2

March 20, 2023 · 3 min · array · array-algo · delete_remove · duplicates-algo · leetcode · repeat · sorted-array · two-pointers · Last updated: Aug 2, 2025

Search a 2D Matrix 1 - Elements sorted row-wise and first integer of each row is greater than last element of previous row is greater than last element of previous row

March 20, 2023 · 5 min · array · binary-search · leetcode · matrix · search · search/binary · sorted-matrix · todo · Last updated: Aug 2, 2025

Text Justification

March 20, 2023 · 6 min · array · daily-coding-problem · leetcode · recursion · simulation · string · Last updated: Aug 2, 2025

Unique Paths in Grid 2 - Count all paths moving right or down with obstacles

March 20, 2023 · 6 min · array · count · ctci · dynamic-programming · leetcode · matrix · path-finding · recursion · Last updated: Jan 20, 2025

Rotate Linked List to Right

March 20, 2023 · 3 min · leetcode · linked-list · linkedlist · two-pointers · Last updated: Aug 2, 2025

Spiral Matrix 2 - Generate

March 20, 2023 · 3 min · array · interviewbit · leetcode · matrix · simulation · spiral · video · Last updated: Aug 2, 2025

Merge Overlapping Intervals

March 20, 2023 · 4 min · array · daily-coding-problem · greedy · interval · leetcode · merge-sort · sorting · Last updated: Aug 2, 2025

Group Anagrams

March 20, 2023 · 5 min · anagram · array · hash-table · leetcode · sorting · string · string-algo · video · Last updated: Aug 11, 2025

Multiply Strings

March 20, 2023 · 18 min · interviewbit · leetcode · math · multiplication · numerical-algo · simulation · string · Last updated: Jul 31, 2025

Trapping Rain Water

March 20, 2023 · 5 min · array · daily-coding-problem · dynamic-programming · leetcode · monotonic-stack · stack · stack/monotonic · tower · two-pointers · Last updated: Aug 2, 2025

Combination Sum 2 - Cant Reuse same element

March 20, 2023 · 2 min · array · backtracking · leetcode · permutation-combination · Last updated: Aug 2, 2025

First Missing Positive

March 20, 2023 · 5 min · array · daily-coding-problem · hash-table · interviewbit · leetcode · missing · Last updated: Aug 2, 2025

Combination Sum 1

March 20, 2023 · 5 min · array · backtracking · leetcode · permutation-combination · todo · video · Last updated: Aug 2, 2025

Find first and last positions of target element in sorted array

March 20, 2023 · 2 min · array · binary-search · divide-n-conquer · duplicates-algo · interviewbit · leetcode · search · search/binary · sorted-array · Last updated: Nov 14, 2024

Search in Rotated Sorted Array

March 20, 2023 · 5 min · array · binary-search · ctci · daily-coding-problem · divide-n-conquer · duplicates-algo · interviewbit · leetcode · rotate · rotated-array · rotated-sorted-array · search · search/binary · sorted-array · video · Last updated: Aug 2, 2025

Add Binary Strings

March 20, 2023 · 5 min · bit-manipulation · bits · interviewbit · leetcode · math · numerical-algo · simulation · string · Last updated: Aug 2, 2025

3Sum - Closest

March 20, 2023 · 2 min · 2sum · array · array-algo · interviewbit · leetcode · n-sum · sorting · sum · two-pointers · Last updated: Aug 2, 2025

February ²⁸

Arranging Coins

February 28, 2023 · 4 min · binary-search · leetcode · math · numerical-algo · search/binary · Last updated: Jul 31, 2025

Count Sub Islands

February 28, 2023 · 5 min · array · breadth-first-search · depth-first-search · dfs · hash-table · leetcode · matrix · union-find · video · Last updated: Aug 2, 2025

Dungeon Game

February 28, 2023 · 21 min · array · dynamic-programming · game-development · leetcode · matrix · Last updated: Aug 2, 2025

Find Nth Node From End Of Linked List

February 28, 2023 · 3 min · linkedlist · Last updated: Aug 2, 2025

Interleaving String

February 28, 2023 · 12 min · dynamic-programming · leetcode · string · Last updated: Aug 3, 2025

Maximum Subarray Min-Product

February 28, 2023 · 6 min · array · counting · depth-first-search · dynamic-programming · graph · hash-table · leetcode · math · memoization · monotonic-stack · prefix-sum · segment-tree · simulation · sorting · stack · stack/monotonic · string · topological-sort · trie · Last updated: Jan 2, 2025

Minimum Number of Days to Disconnect Island

February 28, 2023 · 6 min · array · bfs · breadth-first-search · depth-first-search · dfs · leetcode · matrix · strongly-connected-component · strongly-connected-components · video · Last updated: Jul 31, 2025

Node With Highest Edge Score

February 28, 2023 · 3 min · array · backtracking · binary-search · binary-tree · breadth-first-search · counting · database · depth-first-search · dynamic-programming · graph · greedy · hash-table · heap-priority-queue · leetcode · math · matrix · ordered-set · prefix-sum · simulation · sliding-window · sorting · stack · string · todo · tree · union-find · Last updated: Aug 2, 2025

Non-decreasing Array

February 28, 2023 · 3 min · array · daily-coding-problem · greedy · leetcode · Last updated: Aug 2, 2025

Random Point in Non-overlapping Rectangles

February 28, 2023 · 7 min · array · binary-search · leetcode · math · ordered-set · prefix-sum · randomized · reservoir-sampling · Last updated: Aug 2, 2025

Redundant Connection

February 28, 2023 · 5 min · articulation-point · breadth-first-search · depth-first-search · dfs · disjoint-set · graph · leetcode · union-find · Last updated: Aug 2, 2025

Valid Tic-Tac-Toe State

February 28, 2023 · 5 min · array · game-development · games/tic-tac-toe · leetcode · matrix · todo · Last updated: Aug 2, 2025

Minimum Time to Make Rope Colorful

February 28, 2023 · 2 min · array · dynamic-programming · greedy · leetcode · string · Last updated: Aug 2, 2025

Unique Paths in Grid 3 - Count all paths moving in 4 directions with obstacles and custom start and end

February 28, 2023 · 5 min · array · backtracking · bit-manipulation · dynamic-programming · leetcode · matrix · Last updated: Jun 17, 2024

Majority Element - Boyer–Moore majority vote algorithm

February 27, 2023 · 4 min · array · counting · divide-and-conquer · duplicates-algo · hash-table · leetcode · named-algo-ds/algo · repeat · sorting · Last updated: Aug 2, 2025

Find minimum difference between any two elements

February 23, 2023 · 3 min · array · Last updated: Aug 2, 2025

Increasing Triplet Subsequence

February 23, 2023 · 3 min · array · greedy · increasing · leetcode · subsequence · Last updated: Aug 2, 2025

Patching Array

February 23, 2023 · 6 min · array · greedy · hash-table · leetcode · sorted-array · Last updated: Aug 2, 2025

Reverse Vowels of a String

February 23, 2023 · 2 min · leetcode · reverse · string · two-pointers · Last updated: Aug 2, 2025

Summary Ranges

February 23, 2023 · 3 min · array · array-algo · interval · leetcode · range-tree · sorted-array · unique-array · Last updated: Feb 23, 2025

Game of Life

February 23, 2023 · 4 min · 2013 · aggregation · array · coursera · daily-coding-problem · leetcode · matrix · mental-model · model-thinking · mooc-gam · simulation · Last updated: Aug 2, 2025

Find the Smallest Divisor Given a Threshold

February 23, 2023 · 4 min · array · binary-search · bit-manipulation · breadth-first-search · database · hash-table · leetcode · matrix · Last updated: Aug 2, 2025

Minimum Number of Days to Make m Bouquets

February 23, 2023 · 8 min · array · binary-search · leetcode · search/binary · Last updated: Aug 2, 2025

Split Array Largest Sum

February 23, 2023 · 5 min · array · binary-search · dynamic-programming · greedy · leetcode · prefix-sum · search/binary · Last updated: Aug 6, 2025

Capacity To Ship Packages Within D Days

February 23, 2023 · 6 min · array · binary-search · leetcode · search/binary · Last updated: Aug 2, 2025

Single Element in a Sorted Array

February 21, 2023 · 4 min · array · binary-search · leetcode · search/binary · todo · xor · Last updated: Aug 2, 2025

Range Minimum Query RMQ

February 21, 2023 · 13 min · segment-tree · rmq-range-minimum-query · Last updated: Aug 2, 2025

Fibonacci Numbers

February 13, 2023 · 1 min · fibonacci · Last updated: Jun 3, 2024

January ²⁹

LFU Cache

January 29, 2023 · 5 min · cache · daily-coding-problem · design · design/data-structure · doubly-linked-list · hash-table · leetcode · linked-list · Last updated: Aug 2, 2025

Least Recently Used (LRU) Cache Replacement Algorithm

January 29, 2023 · 1 min · Last updated: Jun 11, 2024

Design LRU Cache

January 29, 2023 · 7 min · cache · daily-coding-problem · design · design/data-structure · doubly-linked-list · hash-table · hashmap · leetcode · linked-list · linkedlist · Last updated: Aug 2, 2025

Cheapest Flights Within K Stops Problem

January 26, 2023 · 8 min · breadth-first-search · daily-coding-problem · depth-first-search · dynamic-programming · graph · heap-priority-queue · leetcode · shortest-path · Last updated: Jun 2, 2024

Insert Interval

January 16, 2023 · 4 min · array · greedy · interval · interviewbit · leetcode · Last updated: Aug 2, 2025

Symmetric Binary Tree

January 10, 2023 · 1 min · binary-tree · breadth-first-search · bt-binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 4, 2025

Gas Station

January 7, 2023 · 8 min · array · circular · greedy · leetcode · search · Last updated: Aug 2, 2025

Single Number 1 - All elements except one occur twice

January 2, 2023 · 3 min · array · bit-manipulation · bits · duplicates-algo · hashing · leetcode · sorting · video · xor · Last updated: Aug 2, 2025

Reverse String

January 2, 2023 · 5 min · ctci · leetcode · reverse · string · string-algo · two-pointers · video · Last updated: Aug 2, 2025

Remove duplicates from Sorted List 1

January 2, 2023 · 1 min · delete_remove · duplicates-algo · leetcode · linked-list · linkedlist · repeat · video · Last updated: Aug 2, 2025

2Sum 2 – Input array is sorted

January 2, 2023 · 6 min · 2sum · array · binary-search · leetcode · n-sum · sum · two-pointers · video · Last updated: Aug 2, 2025

Best Time To Buy And Sell Stock 1 - only one transaction

January 2, 2023 · 8 min · array · daily-coding-problem · divide-n-conquer · dynamic-programming · kadane · leetcode · max-min · sliding-window · stock-algo · todo · two-pointers · video · Last updated: Mar 10, 2025

Check if given string is palindrome or not

January 2, 2023 · 2 min · duplicates-algo · array · array-algo · palindrome · two-pointers · string · video · Last updated: Aug 2, 2025

Merge Two Sorted Arrays

January 2, 2023 · 3 min · array · array-algo · ctci · leetcode · merge-sort · sorted-array · sorting · two-array · two-pointers · Last updated: Aug 2, 2025

Minimize Absolute Difference

January 2, 2023 · 3 min · interviewbit · two-pointers · Last updated: Aug 2, 2025

Move Zeroes at the end of array

January 2, 2023 · 2 min · array · duplicates-algo · leetcode · partition · two-pointers · zero · Last updated: Aug 2, 2025

Smallest difference between two elements from two arrays

January 2, 2023 · 4 min · array-algo · two-array · arithmetic-difference · two-pointers · Last updated: Aug 2, 2025

Split Linked List into two halves fractionally given n

January 2, 2023 · 4 min · linkedlist · split · two-pointers · Last updated: Aug 2, 2025

Squares of a Sorted array

January 2, 2023 · 4 min · array · daily-coding-problem · leetcode · sorting · two-pointers · Last updated: Aug 2, 2025

Two Sum Less Than K

January 2, 2023 · 1 min · array · binary-search · hash-table · leetcode · sliding-window · sorting · string · todo · two-pointers · Last updated: Aug 2, 2025

Valid Palindrome

January 2, 2023 · 8 min · leetcode · palindrome · string · two-pointers · video · Last updated: Aug 2, 2025

Detect Capital

January 2, 2023 · 2 min · leetcode · string · Last updated: Aug 2, 2025

Remove duplicates from Sorted Array 1

January 2, 2023 · 3 min · array · array-algo · delete_remove · duplicates-algo · leetcode · repeat · sorted-array · two-pointers · video · Last updated: Aug 2, 2025

Remove Element

January 2, 2023 · 2 min · array · array-algo · delete_remove · duplicates-algo · leetcode · two-pointers · video · Last updated: Aug 2, 2025

Reverse Linked List

January 2, 2023 · 6 min · daily-coding-problem · leetcode · linked-list · linkedlist · recursion · reverse · two-pointers · video · Last updated: Aug 2, 2025

Linear Search on array

January 2, 2023 · 2 min · array · search · search/linear · Last updated: Aug 2, 2025

Permutations of Array 1

January 2, 2023 · 4 min · array · backtracking · daily-coding-problem · interviewbit · leetcode · todo · Last updated: Aug 2, 2025

Implement stack using resizing of array

January 1, 2023 · 5 min · array · stack · dynamic-memory · Last updated: Aug 2, 2025

Word Pattern 1

January 1, 2023 · 2 min · hash-table · hashmap · leetcode · string · word · Last updated: Aug 2, 2025

2022 ³¹²

December ¹

Cron Cheatsheet

December 26, 2022 · 1 min · Last updated: Apr 17, 2024

November ⁶

Find frequency of a word in a book

November 30, 2022 · 1 min · ctci · duplicates-algo · frequency · design · Last updated: Aug 2, 2025

Evaluation function for Tic-Tac-Toe

November 30, 2022 · 5 min · array · ctci · gaming · hash-table · leetcode · math · matrix · moderate · simulation · todo · Last updated: Oct 31, 2024

Find missing integer in an array with only access to jth bit of elements

November 30, 2022 · 3 min · ctci · integer · bits · Last updated: Jul 22, 2024

Floyd-Warshall Algorithm

November 27, 2022 · 4 min · named-algo-ds/algo · graph · shortest-path · Last updated: Aug 2, 2025

Integer To Roman

November 6, 2022 · 3 min · hash-table · hashing · interviewbit · leetcode · math · string · Last updated: Aug 2, 2025

Roman To Integer

November 6, 2022 · 4 min · daily-coding-problem · greedy · hash-table · hashing · interviewbit · leetcode · math · string · video · Last updated: Aug 2, 2025

October ³

String Compression 2

October 15, 2022 · 4 min · array · binary-search · compression · database · dynamic-programming · enumeration · interactive · leetcode · string · Last updated: Aug 2, 2025

String Compression

October 15, 2022 · 2 min · compression · leetcode · run-length-encoding · string · two-pointers · Last updated: Aug 2, 2025

Number of Dice Rolls With Target Sum

October 2, 2022 · 15 min · dynamic-programming · leetcode · daily-coding-problem · Last updated: Aug 9, 2025

September ¹⁴

Remove Nth Node From End of List

September 28, 2022 · 4 min · ctci · daily-coding-problem · leetcode · linked-list · linkedlist · two-pointers · video · Last updated: Aug 11, 2025

Satisfiability of Equality Equations

September 27, 2022 · 3 min · array · counting · disjoint-set · graph · greedy · hash-table · leetcode · math · sliding-window · string · union-find · Last updated: Aug 2, 2025

Java String Hashcode Function

September 26, 2022 · 3 min · java · string · hashcode · hashing · Last updated: Mar 26, 2025

Valid Anagram

September 24, 2022 · 8 min · anagram · ctci · hash-table · java · leetcode · sorting · string · string-algo · video · Last updated: Aug 2, 2025

Letter Combinations of a Phone Number

September 23, 2022 · 5 min · backtracking · daily-coding-problem · hash-table · leetcode · permutation-combination · string · Last updated: Aug 2, 2025

4Sum

September 23, 2022 · 3 min · 2sum · array · array-algo · hashing · leetcode · n-sum · sorting · sum · two-pointers · Last updated: Aug 2, 2025

Regular Expression Matching Problem

September 23, 2022 · 6 min · daily-coding-problem · dynamic-programming · leetcode · recursion · string · Last updated: Jul 21, 2024

Wildcard Matching

September 23, 2022 · 6 min · dynamic-programming · greedy · leetcode · recursion · string · Last updated: Aug 2, 2025

Add Two Numbers represented as Linked List in Reversed Order

September 23, 2022 · 3 min · interviewbit · leetcode · linked-list · linkedlist · math · recursion · Last updated: Aug 2, 2025

Capitalize the first character of each word in a given text

September 23, 2022 · 4 min · java/8 · collection · Last updated: Aug 2, 2025

Sum of Even Numbers After Queries

September 21, 2022 · 3 min · array · leetcode · simulation · two-pointers · Last updated: Aug 2, 2025

UTF-8 Validation

September 13, 2022 · 5 min · array · bit-manipulation · leetcode · Last updated: Aug 9, 2025

Maximum Height by Stacking Cuboids

September 10, 2022 · 5 min · array · dynamic-programming · leetcode · lis-longest-increasing-subsequence · sorting · Last updated: Aug 2, 2025

Construct String from Binary Tree

September 9, 2022 · 2 min · binary-tree · bt-binary-tree · depth-first-search · leetcode · string · traversal/inorder · tree · Last updated: Aug 2, 2025

August ¹¹⁹

Manachar’s Algorithm - Longest palindromic substring in linear time

August 28, 2022 · 5 min · string-algo · longest · palindrome · substring · named-algo-ds/algo · Last updated: Aug 2, 2025

Reordered Power of 2

August 26, 2022 · 4 min · counting · enumeration · hash-table · leetcode · math · sorting · Last updated: Aug 2, 2025

Max Number of K-Sum Pairs

August 26, 2022 · 4 min · array · hash-table · leetcode · nsum · sorting · two-pointers · Last updated: Aug 2, 2025

Two Sum 4 - Input is Binary Search Tree

August 26, 2022 · 4 min · binary-search-tree · binary-tree · breadth-first-search · bst-binary-search-tree · depth-first-search · hash-table · interviewbit · leetcode · nsum · tree · two-pointers · Last updated: Aug 2, 2025

Number of Arithmetic Triplets

August 26, 2022 · 2 min · array · breadth-first-search · depth-first-search · enumeration · graph · hash-table · leetcode · todo · tree · two-pointers · union-find · Last updated: Aug 2, 2025

2Sum - 0 - closest - Find two elements whose sum is closest to zero

August 25, 2022 · 4 min · array · array-algo · sum · n-sum · 2sum · Last updated: Aug 2, 2025

Binary Search Tree BST Inorder Iterator

August 25, 2022 · 4 min · binary-search-tree · binary-tree · bst-binary-search-tree · design · interviewbit · iterator · leetcode · stack · traversal · traversal/inorder · tree · Last updated: Aug 2, 2025

Two Sum 3 - Data structure design

August 25, 2022 · 4 min · 2sum · array · data-stream · design · hash-table · leetcode · n-sum · sum · todo · two-pointers · Last updated: Aug 2, 2025

Number of Subsequences That Satisfy the Given Sum Condition

August 25, 2022 · 3 min · array · binary-search · data-stream · database · design · dynamic-programming · hash-table · heap-priority-queue · leetcode · monotonic-queue · nsum · queue · sliding-window · sorting · two-pointers · Last updated: Jun 29, 2025

Ransom Note

August 25, 2022 · 2 min · counting · hash-table · leetcode · string · Last updated: Aug 2, 2025

Word Pattern 2

August 25, 2022 · 3 min · backtracking · hash-table · leetcode · string · word · Last updated: Aug 2, 2025

Shift 2D Grid

August 25, 2022 · 3 min · array · binary-tree · breadth-first-search · depth-first-search · design · hash-table · leetcode · matrix · simulation · tree · Last updated: Aug 2, 2025

Next Greater Element 1

August 25, 2022 · 3 min · array · hash-table · leetcode · monotonic-stack · stack · stack/monotonic · Last updated: Aug 2, 2025

Baseball Game

August 25, 2022 · 2 min · array · leetcode · simulation · stack · Last updated: Aug 2, 2025

Morris Traversal

August 24, 2022 · 3 min · bt-binary-tree · traversal · named-algo-ds · traversal/inorder · successor · named-algo-ds/algo · Last updated: Aug 2, 2025

Guess Number Higher or Lower

August 24, 2022 · 2 min · binary-search · divide-n-conquer · interactive · leetcode · search · search/binary · sorted-array · Last updated: Aug 2, 2025

Avoid Overflow when calculating Mid in Binary Search

August 24, 2022 · 4 min · search/binary · Last updated: Aug 2, 2025

Find All Numbers Disappeared in an Array

August 24, 2022 · 1 min · array · hash-table · leetcode · missing · ranged-array · Last updated: Aug 2, 2025

Maximum Number of Balloons

August 24, 2022 · 1 min · counting · hash-table · hashmap · leetcode · string · Last updated: Aug 2, 2025

Single Number 3 - All elements except two occur twice

August 24, 2022 · 4 min · array · array-algo · bit-manipulation · bits · duplicates-algo · leetcode · repeat · todo · xor · Last updated: Aug 2, 2025

Find Pivot Index

August 23, 2022 · 3 min · array · leetcode · prefix-sum · Last updated: Aug 2, 2025

Path Sum 1 - Check if root to leaf path exists

August 23, 2022 · 2 min · binary-tree · breadth-first-search · bt-binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 11, 2025

Power of Four

August 23, 2022 · 3 min · bit-manipulation · leetcode · math · recursion · Last updated: Aug 2, 2025

Explain (n & (n-1)) == 0

August 23, 2022 · 1 min · ctci · bits · Last updated: Aug 2, 2025

Power of Two

August 23, 2022 · 3 min · bit-manipulation · bits · leetcode · math · recursion · Last updated: Aug 2, 2025

x&(x-1) Explained

August 23, 2022 · 4 min · bits · explained · video · Last updated: Aug 2, 2025

Calculate Rolling Hashcode for String

August 20, 2022 · 5 min · Last updated: Nov 9, 2024

Optimized Brute Force String Search Algorithm

August 20, 2022 · 3 min · string · Last updated: Aug 2, 2025

Naive Brute Force String Search Algorithm

August 20, 2022 · 3 min · string · string-algo · pattern-matching · Last updated: Aug 2, 2025

Can Place Flowers

August 20, 2022 · 3 min · array · greedy · leetcode · Last updated: Aug 2, 2025

Remove duplicates from Sorted List 2

August 20, 2022 · 2 min · delete_remove · duplicates-algo · leetcode · linked-list · linkedlist · repeat · two-pointers · video · Last updated: Aug 2, 2025

Isomorphic Strings

August 20, 2022 · 3 min · hash-table · isomorphic · leetcode · string · string-algo · video · Last updated: Aug 2, 2025

Kth Largest Element in a Stream

August 20, 2022 · 2 min · binary-search-tree · binary-tree · data-stream · design · heap-priority-queue · heap/min · leetcode · stream · tree · video · Last updated: Aug 2, 2025

Number of 1 Bits

August 20, 2022 · 8 min · bit-manipulation · bits · count · divide-and-conquer · leetcode · todo · video · Last updated: Jul 24, 2025

Valid Palindrome 2

August 20, 2022 · 2 min · greedy · leetcode · palindrome · string · two-pointers · Last updated: Aug 2, 2025

Min Cost Climbing Stairs

August 20, 2022 · 4 min · array · dynamic-programming · leetcode · Last updated: May 22, 2024

Unique Email Addresses

August 20, 2022 · 2 min · array · hash-table · leetcode · string · Last updated: Aug 2, 2025

Length of Last Word

August 20, 2022 · 2 min · leetcode · string · string-algo · video · Last updated: Aug 2, 2025

Search Insert Position in sorted array

August 20, 2022 · 3 min · array · binary-search · divide-n-conquer · duplicates-algo · leetcode · search · search/binary · sorted-array · Last updated: Aug 2, 2025

Remove Linked List Elements

August 20, 2022 · 2 min · delete_remove · leetcode · linked-list · linkedlist · recursion · Last updated: Aug 2, 2025

Min Stack

August 20, 2022 · 4 min · ctci · daily-coding-problem · design · leetcode · max-min · queue · stack · Last updated: Aug 2, 2025

Happy Number

August 18, 2022 · 2 min · cycle-detection · hash-table · leetcode · math · two-pointers · Last updated: Jul 31, 2025

Lowest Common Ancestor of a Binary Tree 4 - for array of nodes

August 18, 2022 · 2 min · binary-tree · database · depth-first-search · hash-table · leetcode · string · tree · Last updated: Aug 2, 2025

Lowest Common Ancestor Definition

August 18, 2022 · 1 min · bt-binary-tree · bst-binary-search-tree · n-ary-tree · lowest-common-ancestor · Last updated: Aug 2, 2025

Lowest Common Ancestor of a Binary Tree 3 - Given Parent Pointer

August 18, 2022 · 4 min · binary-tree · bt-binary-tree · daily-coding-problem · database · hash-table · leetcode · lowest · tree · two-pointers · Last updated: Jan 2, 2025

Lowest Common Ancestor for a n-ary Tree

August 18, 2022 · 4 min · bt-binary-tree · n-ary-tree · Last updated: Aug 2, 2025

Lowest Common Ancestor of a Binary Tree 2 - Nodes may not exist in Tree

August 18, 2022 · 3 min · array · binary-tree · database · depth-first-search · leetcode · simulation · tree · Last updated: May 21, 2024

Replace Elements with Greatest Element on Right Side

August 17, 2022 · 2 min · array · binary-search · leetcode · sorting · Last updated: Aug 2, 2025

Invert Binary Tree

August 17, 2022 · 4 min · binary-tree · breadth-first-search · bt-binary-tree · daily-coding-problem · depth-first-search · interviewbit · leetcode · mirror · tree · video · Last updated: Aug 2, 2025

First Unique Character in a String

August 16, 2022 · 5 min · array-algo · counting · duplicates-algo · hash-table · leetcode · non-duplicated-algo · queue · repeat · string · string-algo · Last updated: Aug 2, 2025

Substring with Concatenation of All Words

August 14, 2022 · 4 min · hash-table · interviewbit · leetcode · sliding-window · string · string-algo · substring · Last updated: Aug 2, 2025

Merge Two Binary Trees

August 12, 2022 · 2 min · binary-tree · breadth-first-search · bt-binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 10, 2025

Palindrome Linked List

August 12, 2022 · 3 min · leetcode · linked-list · linkedlist · palindrome · recursion · stack · two-pointers · Last updated: Aug 2, 2025

Climbing Stairs - Take atmost 3 steps

August 12, 2022 · 8 min · dynamic-programming · Last updated: Aug 2, 2025

Intersection of Two Sorted Array

August 11, 2022 · 2 min · sorted-array · two-array · intersection · Last updated: Aug 2, 2025

Swap two number in place without temporary variables

August 11, 2022 · 3 min · ctci · bits · number · moderate · xor · Last updated: Aug 2, 2025

Swap Kth node from beginning with Kth node from end in a Linked List

August 11, 2022 · 3 min · array · depth-first-search · leetcode · linked-list · linkedlist · swap · two-pointers · union-find · Last updated: Aug 2, 2025

Subarray with sum divisible by k

August 11, 2022 · 3 min · sum · subarray · subarray-sum · Last updated: Aug 2, 2025

Second largest element in binary search tree

August 11, 2022 · 3 min · bst-binary-search-tree · max-min · second-max-min · daily-coding-problem · Last updated: Aug 2, 2025

Replace all occurrences of a pattern in a text by another string

August 11, 2022 · 5 min · pattern-matching · substring · Last updated: Aug 2, 2025

Reverse a stack in place using recursion

August 11, 2022 · 3 min · stack · reverse · Last updated: Aug 2, 2025

Reverse the given Array without using built in function

August 11, 2022 · 3 min · array · array-algo · reverse · two-pointers · stack · Last updated: Aug 2, 2025

Reverse a string in C using as little additional memory as possible

August 11, 2022 · 2 min · bits · reverse · Last updated: Aug 2, 2025

Print all sub sequences of a given array

August 11, 2022 · 3 min · array · array-algo · Last updated: Aug 2, 2025

Pain Fence

August 11, 2022 · 4 min · dynamic-programming · hash-table · leetcode · Last updated: Aug 2, 2025

Number of elements less than or equal to a given number in a given subarray

August 10, 2022 · 6 min · binary-indexed-tree · Last updated: Aug 2, 2025

Minimum Number of Deletions Of a String

August 10, 2022 · 7 min · string · string-algo · Last updated: Aug 2, 2025

Minimum Distance Between Two Elements in an Array

August 10, 2022 · 6 min · array-algo · shortest-path · max-min · distance · todo · Last updated: Aug 2, 2025

Merge K Sorted Arrays

August 10, 2022 · 6 min · array · array-algo · median · k-sorted · merge-sort · Last updated: Aug 2, 2025

Maximum Product of Three Numbers

August 10, 2022 · 3 min · array · daily-coding-problem · greedy · interviewbit · leetcode · math · max-min · product · sorting · Last updated: Aug 2, 2025

Maximum Pairwise Product 2 - Find pair with maximum product in array of Integers

August 10, 2022 · 5 min · product · max-min · pair_tuple · Last updated: Aug 2, 2025

Shortest Unsorted Continuous Subarray

August 10, 2022 · 11 min · array · greedy · leetcode · monotonic-stack · sorting · stack · two-pointers · Last updated: Aug 8, 2025

Maximum Difference between two elements in array

August 10, 2022 · 3 min · array · array-algo · todo · Last updated: Aug 2, 2025

Maximum and minimum sum subsequences at a distance greater than equal to M

August 10, 2022 · 6 min · array-algo · sum · distance · Last updated: Aug 2, 2025

Maximize gems collected with an even number of red houses

August 10, 2022 · 4 min · max-min · Last updated: Aug 2, 2025

Maximum gain in a two-player game with picking elements from array ends

August 10, 2022 · 5 min · game-development · array-algo · search · max-min · Last updated: Aug 2, 2025

Nuts and Bolts Problem OR Lock and Key

August 10, 2022 · 7 min · duplicates-algo · array · array-algo · Last updated: Aug 2, 2025

Given an array count max number of surpassers

August 10, 2022 · 4 min · array-algo · max-min · merge-sort · Last updated: Aug 2, 2025

Implement stack using linked list

August 10, 2022 · 4 min · stack · linkedlist · Last updated: Aug 2, 2025

Implement stack using an array

August 10, 2022 · 6 min · leetcode · array · stack · Last updated: Aug 2, 2025

Implement Exponentiation using Bitwise Operator

August 10, 2022 · 2 min · Last updated: Jul 31, 2025

Check Currency Arbitrage with Bellman Ford

August 10, 2022 · 5 min · graph · daily-coding-problem · forex · arbitrage · Last updated: Aug 2, 2025

Integer to English Words

August 10, 2022 · 4 min · ctci · duplicates-algo · greedy · hashing · integer · leetcode · math · recursion · string · video · Last updated: Aug 2, 2025

Generate All Strings of n bits

August 10, 2022 · 2 min · string · bits · backtracking · subset · Last updated: Aug 2, 2025

Swap alternate nodes in a singly linked list

August 10, 2022 · 2 min · linkedlist · swap · pair_tuple · alternate · Last updated: Aug 2, 2025

Split Linked List at the middle

August 10, 2022 · 3 min · leetcode · linkedlist · split · Last updated: Aug 2, 2025

Merge a Linked list into another at Alternate Positions

August 10, 2022 · 4 min · linkedlist · merge-sort · alternate · Last updated: Aug 2, 2025

Fizz Buzz

August 10, 2022 · 7 min · leetcode · math · simulation · string · Last updated: Jul 31, 2025

Find smallest and second smallest elements in an array

August 10, 2022 · 2 min · array · array-algo · Last updated: Aug 2, 2025

Row with maximum number of 1s in sorted binary matrix

August 10, 2022 · 4 min · divide-n-conquer · matrix · Last updated: Aug 2, 2025

Find largest three elements in an array

August 9, 2022 · 3 min · array · array-algo · max · Last updated: Aug 2, 2025

Intersection of Three Sorted Arrays

August 9, 2022 · 4 min · array · array-algo · backtracking · binary-search · binary-search-tree · binary-tree · breadth-first-search · counting · depth-first-search · dynamic-programming · hash-table · leetcode · math · sorting · stack · string · tree · two-pointers · Last updated: Aug 2, 2025

Snakes and Ladders

August 9, 2022 · 5 min · array · bfs · breadth-first-search · graph · leetcode · matrix · Last updated: Aug 2, 2025

Find all prime factors of given number

August 9, 2022 · 3 min · primality · numerical-algo · factor · Last updated: Jul 31, 2025

Find all unique combinations of factors for given number

August 9, 2022 · 3 min · factor · numerical-algo · Last updated: Jul 31, 2025

Excel Sheet Column Number

August 8, 2022 · 3 min · excel · leetcode · math · string · todo · Last updated: Aug 2, 2025

Deepest Left Node in a Binary Tree

August 8, 2022 · 4 min · bt-binary-tree · Last updated: Aug 2, 2025

Calculate the number of valid stack permutations

August 8, 2022 · 2 min · stack · Last updated: Aug 2, 2025

Check if number sequence can be generated using stack push and pop operations

August 8, 2022 · 3 min · stack · Last updated: Aug 2, 2025

Validate stack operation sequence

August 8, 2022 · 2 min · stack · Last updated: Aug 2, 2025

Validate stack permutation based on triplet condition

August 8, 2022 · 3 min · stack · Last updated: Aug 2, 2025

Check If an Integer’s Bit Representation Is a Palindrome

August 7, 2022 · 4 min · integer · bits · palindrome · Last updated: Aug 2, 2025

Count Negative Numbers in a Sorted Matrix

August 7, 2022 · 3 min · array · binary-search · count · data-stream · design · leetcode · math · matrix · queue · sorted-array · sorted-matrix · Last updated: Aug 2, 2025

Count and Say Sequence

August 7, 2022 · 5 min · count · leetcode · numerical-algo · sequence · string · Last updated: Aug 2, 2025

Compare Version Numbers

August 7, 2022 · 3 min · comparator · leetcode · string · two-pointers · video · Last updated: Aug 2, 2025

ZigZag Conversion

August 7, 2022 · 2 min · convert · leetcode · string · string-algo · zigzag · Last updated: Aug 6, 2025

Check if two given matrices are identical

August 7, 2022 · 4 min · matrix · Last updated: Aug 2, 2025

Bulls and Cows

August 7, 2022 · 6 min · counting · hash-table · leetcode · string · Last updated: Aug 2, 2025

Design Search Autocomplete System

August 7, 2022 · 8 min · data-stream · depth-first-search · design · design/data-structure · heap-priority-queue · leetcode · sorting · string · trie · Last updated: Aug 2, 2025

Sentence Screen Fitting

August 7, 2022 · 6 min · array · dynamic-programming · greedy · leetcode · string · Last updated: Aug 2, 2025

Expression Add Operators

August 7, 2022 · 7 min · backtracking · dfs · leetcode · math · operator · path-finding · string · Last updated: Aug 2, 2025

Next Greater Element 3 - Find smallest number larger than given number using same digits same digits

August 7, 2022 · 3 min · greedy · leetcode · math · string · two-pointers · Last updated: Aug 2, 2025

Next Greater number with given set of digits

August 7, 2022 · 5 min · Last updated: Aug 2, 2025

Largest Number From Given Numbers

August 6, 2022 · 3 min · array · comparator · greedy · interviewbit · largest · leetcode · numerical-algo · sorting · string · video · Last updated: Jul 31, 2025

Plus One 1 - Given number as array plus one

August 4, 2022 · 3 min · add · add-one · array · array-algo · interviewbit · leetcode · math · numerical-algo · Last updated: Jul 31, 2025

My Calendar 1

August 3, 2022 · 4 min · array · binary-search · design · leetcode · ordered-set · segment-tree · Last updated: Aug 2, 2025

Maximum Number of Groups Entering a Competition

August 3, 2022 · 4 min · array · binary-search · greedy · leetcode · math · Last updated: Aug 2, 2025

Make Array Zero by Subtracting Equal Amounts

August 2, 2022 · 2 min · array · greedy · hash-table · hashing · heap-priority-queue · leetcode · simulation · sorting · Last updated: Aug 2, 2025

Kth Smallest Element in a Sorted Matrix

August 2, 2022 · 18 min · array · binary-search · heap-priority-queue · leetcode · matrix · sorting · Last updated: Aug 2, 2025

July ²¹

Repeated Substring Pattern

July 13, 2022 · 2 min · leetcode · string · string-matching · todo · Last updated: Aug 2, 2025

Print FooBar Alternately Problem

July 10, 2022 · 12 min · concurrency · leetcode · Last updated: Aug 2, 2025

Print in Order Problem

July 10, 2022 · 4 min · concurrency · leetcode · Last updated: Nov 29, 2024

Print Zero Even Odd Problem

July 10, 2022 · 7 min · concurrency · leetcode · Last updated: Aug 2, 2025

Paint House 1 - N houses with 3 colors with no two adjacent houses with same color color

July 8, 2022 · 7 min · array · color · dynamic-programming · leetcode · matrix · Last updated: Aug 2, 2025

Short Encoding of Words

July 6, 2022 · 6 min · array · hash-table · leetcode · string · trie · Last updated: Aug 2, 2025

Course Schedule 3

July 6, 2022 · 2 min · array · greedy · heap-priority-queue · leetcode · sorting · Last updated: Aug 2, 2025

Moving Average of Last N numbers in a Stream

July 6, 2022 · 4 min · array · average · data-stream · design · leetcode · median · queue · rolling-median · stream · streaming · Last updated: Aug 2, 2025

Moving Average of All Numbers in Stream

July 6, 2022 · 1 min · stream · rolling-median · Last updated: Aug 2, 2025

Maximum Points You Can Obtain from Cards Problem

July 6, 2022 · 3 min · array · inversion · leetcode · prefix-sum · sliding-window · Last updated: Jul 3, 2024

Design HashMap

July 5, 2022 · 4 min · array · design · design/data-structure · hash-function · hash-table · leetcode · linked-list · Last updated: Aug 2, 2025

Design Hashset

July 5, 2022 · 2 min · array · design · design/data-structure · hash-function · hash-table · leetcode · linked-list · Last updated: Aug 2, 2025

Ugly Number

July 5, 2022 · 2 min · leetcode · math · numerical-algo · video · Last updated: Jul 31, 2025

Super Ugly Number

July 5, 2022 · 5 min · array · duplicates-algo · dynamic-programming · leetcode · math · Last updated: Jul 31, 2025

Rearrange Array Elements by Sign

July 4, 2022 · 2 min · alternate · array · backtracking · bit-manipulation · bitmask · counting · database · duplicates-algo · dynamic-programming · enumeration · geometry · hash-function · hash-table · leetcode · math · rearrange-array · rolling-hash · simulation · sliding-window · sorting · string · two-pointers · union-find · Last updated: Aug 2, 2025

Basic Calculator 4

July 4, 2022 · 11 min · hash-table · leetcode · math · numerical-algo · recursion · stack · string · todo · Last updated: Aug 2, 2025

Basic Calculator 3

July 4, 2022 · 5 min · array · divide-and-conquer · leetcode · math · matrix · numerical-algo · recursion · stack · string · todo · tree · Last updated: Aug 2, 2025

Basic Calculator 2 Problem

July 4, 2022 · 5 min · infix · leetcode · math · numerical-algo · rpn · stack · string · Last updated: Jul 28, 2024

Basic Calculator 1

July 4, 2022 · 3 min · daily-coding-problem · leetcode · math · numerical-algo · recursion · stack · string · Last updated: Aug 2, 2025

What is infix, postfix and prefix Expressions

July 4, 2022 · 1 min · stack · rpn · infix · Last updated: Aug 2, 2025

Best Meeting Point

July 3, 2022 · 7 min · array · coordinate-geometry · leetcode · math · matrix · sorting · Last updated: Aug 1, 2025

June ⁵⁷

Product Sales Analysis II

June 27, 2022 · 2 min · database · leetcode · sql · Last updated: Sep 26, 2024

Product Sales Analysis I

June 27, 2022 · 2 min · database · leetcode · sql · Last updated: Dec 30, 2024

Swap Salary Problem

June 27, 2022 · 2 min · database · leetcode · sql · Last updated: Nov 27, 2024

Not Boring Movies Problem

June 27, 2022 · 2 min · database · leetcode · Last updated: Sep 26, 2024

Leetcode 619 - Biggest Single Number Problem

June 27, 2022 · 1 min · database · leetcode · Last updated: Sep 26, 2024

Shortest Distance Problem

June 27, 2022 · 1 min · database · leetcode · sql · Last updated: Sep 26, 2024

Leetcode 603 - Consecutive Available Seats Problem

June 26, 2022 · 1 min · database · leetcode · sql · Last updated: Sep 26, 2024

Friend Requests I - Overall Acceptance Rate Problem

June 26, 2022 · 3 min · database · leetcode · Last updated: Sep 26, 2024

Find Customer Referee Problem

June 26, 2022 · 2 min · database · leetcode · sql · Last updated: Sep 26, 2024

Employee Bonus Problem

June 26, 2022 · 2 min · database · leetcode · sql · Last updated: Sep 26, 2024

Game Play Analysis II

June 26, 2022 · 2 min · database · leetcode · sql · Last updated: Sep 26, 2024

Rising Temperature Problem

June 26, 2022 · 2 min · database · leetcode · sql · Last updated: Sep 25, 2024

Duplicate Emails Problem

June 26, 2022 · 1 min · database · leetcode · sql · Last updated: Sep 26, 2024

Employees Earning More Than Their Managers Problem

June 26, 2022 · 2 min · database · leetcode · sql · Last updated: Sep 25, 2024

Weather Type in Each Country Problem

June 26, 2022 · 1 min · database · leetcode · Last updated: Sep 26, 2024

The Winner University Problem

June 26, 2022 · 2 min · array · database · graph · greedy · leetcode · linked-list · queue · simulation · sql · string · union-find · Last updated: Sep 26, 2024

Customer Order Frequency Problem

June 26, 2022 · 2 min · array · counting · database · hash-table · leetcode · math · sql · string · Last updated: Sep 26, 2024

The Number of Users That Are Eligible for Discount Problem

June 26, 2022 · 1 min · array · backtracking · bit-manipulation · counting · database · dynamic-programming · enumeration · greedy · hash-table · heap-priority-queue · leetcode · prefix-sum · simulation · stack · string · Last updated: Sep 26, 2024

Low-Quality Problems

June 26, 2022 · 1 min · database · greedy · leetcode · string · Last updated: Sep 26, 2024

Friendly Movies Streamed Last Month Problem

June 26, 2022 · 1 min · database · hash-table · leetcode · sql · string · Last updated: Sep 26, 2024

Find the Team Size Problem

June 26, 2022 · 1 min · array · backtracking · binary-search-tree · binary-tree · breadth-first-search · database · depth-first-search · leetcode · math · sorting · string · tree · Last updated: Sep 26, 2024

User Activity for the Past 30 Days II

June 26, 2022 · 1 min · database · leetcode · sql · Last updated: Sep 26, 2024

Random Flip Matrix

June 22, 2022 · 4 min · fisher-yates · hash-table · leetcode · math · randomized · reservoir-sampling · Last updated: Aug 2, 2025

Random Pick Index

June 21, 2022 · 3 min · hash-table · leetcode · math · randomized · reservoir-sampling · todo · Last updated: Aug 2, 2025

Reservoir Sampling Explained

June 21, 2022 · 6 min · probability · random · numerical-algo · daily-coding-problem · stream · Last updated: Aug 2, 2025

Fisher-Yates Shuffle vs Reservoir Sampling

June 21, 2022 · 1 min · named-algo-ds/algo · reservoir-sampling · Last updated: Aug 2, 2025

Blum Floyd Pratt Rivest Tarjan Algorithm

June 20, 2022 · 2 min · named-algo-ds/algo · selection · Last updated: Aug 2, 2025

Add Digits in Number

June 20, 2022 · 2 min · leetcode · math · number-theory · numerical-algo · simulation · Last updated: Aug 2, 2025

Implement Power Function 2

June 19, 2022 · 2 min · interviewbit · search/binary · Last updated: Jul 31, 2025

Reverse Linked List 2 - between m and n

June 19, 2022 · 3 min · interviewbit · leetcode · linked-list · linkedlist · reverse · Last updated: Aug 2, 2025

Get sqrt nth node in Linked List

June 19, 2022 · 4 min · linkedlist · Last updated: Aug 2, 2025

Equal Average Partition

June 19, 2022 · 7 min · interviewbit · Last updated: Aug 2, 2025

Binary Tree Cameras

June 17, 2022 · 3 min · array · binary-tree · bt-binary-tree · depth-first-search · dfs · dynamic-programming · enumeration · greedy · hash-table · leetcode · math · sorting · string · traversal/postorder · tree · two-pointers · Last updated: Aug 2, 2025

Longest String Chain

June 15, 2022 · 3 min · array · dynamic-programming · hash-table · leetcode · sorting · string · two-pointers · Last updated: Aug 2, 2025

Delete Operation for Two Strings

June 14, 2022 · 2 min · dynamic-programming · leetcode · string · Last updated: Aug 2, 2025

Maximum Triangle path sum from top to bottom

June 14, 2022 · 3 min · array · dynamic-programming · max-min · path-finding · pathsum · sum · daily-coding-problem · Last updated: Aug 2, 2025

Minimum Triangle path sum from top to bottom

June 14, 2022 · 8 min · array · dynamic-programming · leetcode · max-min · path-finding · pathsum · sum · Last updated: Aug 2, 2025

Number Complement

June 12, 2022 · 4 min · array · bit-manipulation · bits · counting · hash-table · leetcode · video · Last updated: Aug 2, 2025

First Bad Version

June 12, 2022 · 8 min · binary-search · interactive · leetcode · search/binary · Last updated: Aug 2, 2025

Word Search 1 - Find if word exists

June 12, 2022 · 4 min · array · backtracking · daily-coding-problem · depth-first-search · leetcode · matrix · string · word · video · Last updated: Aug 2, 2025

Word Search 2 - Return All Words

June 12, 2022 · 5 min · array · backtracking · leetcode · matrix · string · trie · word · Last updated: Aug 4, 2025

Longest Substring Without Repeating Characters

June 12, 2022 · 6 min · duplicates-algo · dynamic-programming · hash-table · leetcode · longest · sliding-window · string · substring · video · Last updated: Aug 2, 2025

Sum Root to Leaf Numbers

June 12, 2022 · 6 min · binary-tree · binary-tree-leaf · bt-binary-tree · depth-first-search · leetcode · tree · Last updated: Aug 2, 2025

All Possible Full Binary Trees

June 11, 2022 · 4 min · binary-tree · bt-binary-tree · dynamic-programming · leetcode · memoization · recursion · tree · Last updated: Aug 2, 2025

Maximum Sum Circular Subarray

June 11, 2022 · 5 min · array · daily-coding-problem · divide-and-conquer · dynamic-programming · greedy · inversion · kadane · leetcode · monotonic-queue · prefix-sum · queue · Last updated: Aug 2, 2025

Calculate Hash Code for String

June 10, 2022 · 4 min · Last updated: Nov 8, 2024

Top K Frequent Words

June 9, 2022 · 4 min · bucket-sort · counting · frequency · hash-table · heap-priority-queue · kth · leetcode · sorting · stream · string · topk · trie · Last updated: Aug 15, 2025

H-Index 2

June 9, 2022 · 2 min · array · binary-search · leetcode · search/binary · sorting · Last updated: Aug 2, 2025

Weighted Graph Representation - Adjacency List of Pair and map

June 8, 2022 · 1 min · Last updated: Aug 2, 2025

Coin Change with Fewest Number of Coins Given Canonical System and Infinite Supply

June 8, 2022 · 3 min · greedy · coin · max-min · daily-coding-problem · Last updated: Aug 2, 2025

Delete non-tail Node in linked list, Given only access to that Node

June 8, 2022 · 2 min · ctci · delete_remove · leetcode · linked-list · linkedlist · video · Last updated: Aug 2, 2025

H-Index

June 7, 2022 · 5 min · array · bucketsort · counting-sort · leetcode · search/binary · sorting · Last updated: Aug 11, 2025

Binary Tree Traversal - Vertical Order Traversal

June 6, 2022 · 4 min · binary-tree · breadth-first-search · bt-binary-tree · depth-first-search · hash-table · leetcode · sorting · traversal · tree · vertical · Last updated: May 22, 2024

Design Add and Search Words Data Structure

June 6, 2022 · 4 min · depth-first-search · design · leetcode · string · tree-ds · trie · Last updated: Aug 2, 2025

Map-based Trie Implementation

June 6, 2022 · 4 min · concept · trie · implementation · Last updated: Aug 2, 2025

Max Chunks to Make Sorted

June 1, 2022 · 6 min · array · greedy · leetcode · monotonic-stack · sorting · stack · stack/monotonic · video · Last updated: Aug 2, 2025

May ²⁸

NSL - Nearest Smallest Element to Left of Every Element

May 29, 2022 · 2 min · Last updated: Aug 2, 2025

NSR - Nearest Smaller Element to Right of every element

May 29, 2022 · 2 min · stack/monotonic · Last updated: Aug 2, 2025

NGR - Nearest Greater Element to Right of every element

May 29, 2022 · 2 min · stack/monotonic · Last updated: Aug 2, 2025

NGL - Nearest Greater Element to Left of every element

May 29, 2022 · 2 min · Last updated: Aug 2, 2025

Score of Parentheses

May 29, 2022 · 6 min · leetcode · parentheses · stack · string · Last updated: Aug 2, 2025

Verify Preorder Sequence in Binary Search Tree

May 27, 2022 · 3 min · array · binary-search-tree · binary-tree · leetcode · monotonic-stack · recursion · stack · tree · Last updated: Aug 2, 2025

Find right-most cousin in a binary tree

May 27, 2022 · 3 min · bt-binary-tree · traversal · traversal/level-order · Last updated: Aug 2, 2025

Number of Steps to Reduce a Number to Zero

May 27, 2022 · 2 min · bit-manipulation · bits · leetcode · math · Last updated: Aug 2, 2025

Design Circular Queue

May 22, 2022 · 7 min · array · design · leetcode · linked-list · queue · queue/circular · Last updated: Aug 2, 2025

Graph Representation - Adjacency List and Map

May 21, 2022 · 1 min · graph · graph-representation · Last updated: Aug 2, 2025

Graph Representation - Adjacency List (with isDirected)

May 21, 2022 · 2 min · graph · Last updated: Aug 2, 2025

Detect Squares

May 20, 2022 · 5 min · array · backtracking · counting · database · design · design/data-structure · dynamic-programming · enumeration · greedy · hash-table · heap-priority-queue · leetcode · math · matrix · memoization · ordered-set · prefix-sum · sorting · stack · string · Last updated: Jul 28, 2025

Path with Maximum Probability

May 18, 2022 · 6 min · array · bellman-ford · dijkstra · graph · heap-priority-queue · leetcode · shortest-path · video · Last updated: Jul 31, 2025

Find the City With the Smallest Number of Neighbors at a Threshold Distance Problem

May 18, 2022 · 11 min · dijkstra · dynamic-programming · floyd-warshall · graph · leetcode · shortest-path · video · Last updated: Jul 31, 2025

Minimize Malware Spread 2

May 18, 2022 · 8 min · array · breadth-first-search · depth-first-search · graph · hash-table · leetcode · union-find · Last updated: Aug 2, 2025

Average Waiting Time

May 17, 2022 · 4 min · array · counting · greedy · heap-priority-queue · leetcode · prefix-sum · simulation · sliding-window · string · Last updated: Aug 2, 2025

Richest Customer Wealth

May 17, 2022 · 1 min · array · greedy · hash-table · leetcode · matrix · monotonic-stack · prefix-sum · stack · Last updated: Aug 2, 2025

Camelcase Matching

May 17, 2022 · 2 min · array · leetcode · string · string-algo · string-matching · trie · two-pointers · Last updated: Aug 2, 2025

Best Time To Buy And Sell Stock - Any number of times - Overlapping Transactions

May 17, 2022 · 2 min · stock-algo · Last updated: Aug 2, 2025

Car Fleet

May 7, 2022 · 7 min · array · leetcode · monotonic-stack · sorting · stack · stack/monotonic · Last updated: Aug 2, 2025

Maximum Length of a Concatenated String with Unique Characters

May 6, 2022 · 3 min · array · backtracking · bit-manipulation · breadth-first-search · concurrency · database · depth-first-search · design · dynamic-programming · graph · greedy · hash-table · leetcode · math · simulation · sorting · string · todo · topological-sort · tree · Last updated: Aug 2, 2025

Check If Two String Arrays are Equivalent

May 6, 2022 · 3 min · array · binary-tree · depth-first-search · greedy · leetcode · prefix-sum · sorting · string · todo · tree · Last updated: Aug 2, 2025

Minimum Remove to Make Valid Parentheses

May 6, 2022 · 4 min · array · daily-coding-problem · database · greedy · leetcode · math · matrix · number-theory · parentheses · simulation · stack · string · Last updated: Aug 2, 2025

Serialize and Deserialize N-Ary Tree

May 5, 2022 · 5 min · breadth-first-search · depth-first-search · leetcode · n-ary-tree · string · tree · Last updated: Aug 2, 2025

Minimum Interval to Include Each Query

May 3, 2022 · 5 min · array · binary-search · counting · database · hash-table · heap · heap-priority-queue · leetcode · line-sweep · prefix-sum · sliding-window · sorting · todo · two-pointers · Last updated: Aug 2, 2025

Stickers to Spell Word

May 3, 2022 · 8 min · array · backtracking · bit-manipulation · bitmask · dynamic-programming · leetcode · string · Last updated: Aug 2, 2025

Median Definition

May 3, 2022 · 1 min · Last updated: Aug 2, 2025

Median of Two Sorted Array of Equal or Same Size

May 2, 2022 · 6 min · search/binary · divide-n-conquer · todo · Last updated: Aug 2, 2025

April ⁶⁰

4Sum - Output in Sorted Order

April 30, 2022 · 4 min · interviewbit · todo · Last updated: Aug 2, 2025

4Sum 2 - 4 Different Arrays

April 30, 2022 · 4 min · array · hash-table · leetcode · Last updated: Aug 2, 2025

Remove Covered Intervals

April 30, 2022 · 2 min · array · greedy · leetcode · sorting · Last updated: Aug 2, 2025

Longest Happy String

April 29, 2022 · 5 min · greedy · heap-priority-queue · heap/max · leetcode · string · video · Last updated: Aug 2, 2025

Find minimum difference Element in sorted array

April 28, 2022 · 5 min · divide-n-conquer · search · sorted-array · search/binary · floor · ceiling · Last updated: Aug 2, 2025

Open the Lock

April 28, 2022 · 4 min · array · bfs · breadth-first-search · hash-table · leetcode · shortest-path · string · Last updated: Aug 10, 2025

Partition Labels

April 28, 2022 · 3 min · greedy · hash-table · leetcode · string · two-pointers · Last updated: Aug 2, 2025

Trim a Binary Search Tree BST

April 28, 2022 · 2 min · binary-search-tree · binary-tree · bst-binary-search-tree · depth-first-search · dfs · leetcode · tree · Last updated: Aug 2, 2025

Flatten binary tree to linked list in order of preorder traversal

April 26, 2022 · 3 min · binary-tree · bt-binary-tree · convert · depth-first-search · interviewbit · leetcode · linked-list · stack · traversal/preorder · tree · Last updated: Aug 2, 2025

Merge Triplets to Form Target Triplet

April 26, 2022 · 5 min · array · binary-search · binary-search-tree · binary-tree · dynamic-programming · greedy · leetcode · matrix · memoization · ordered-set · tree · Last updated: Aug 1, 2025

Encode and Decode TinyURL

April 26, 2022 · 3 min · daily-coding-problem · design · hash-function · hash-table · leetcode · string · Last updated: Aug 2, 2025

Flip Equivalent Binary Trees

April 26, 2022 · 4 min · bfs · binary-tree · bt-binary-tree · depth-first-search · dfs · leetcode · recursion · tree · video · Last updated: Aug 2, 2025

Maximum Product of the Length of Two Palindromic Subsequences

April 25, 2022 · 6 min · backtracking · binary-tree · bit-manipulation · bitmask · database · depth-first-search · dynamic-programming · game-theory · leetcode · math · string · todo · tree · union-find ·

Minimum Difference Between Highest and Lowest of K Scores

April 25, 2022 · 4 min · array · backtracking · bit-manipulation · bitmask · database · divide-and-conquer · dynamic-programming · greedy · heap-priority-queue · leetcode · prefix-sum · quickselect · sliding-window · sorting · string · todo ·

Minimum Number of Days to Eat N Oranges

April 25, 2022 · 5 min · database · dynamic-programming · greedy · hash-function · hash-table · leetcode · memoization · rolling-hash · string · todo ·

Eliminate Maximum Number of Monsters

April 25, 2022 · 8 min · array · binary-search · breadth-first-search · dynamic-programming · enumeration · game-theory · geometry · graph · greedy · hash-function · leetcode · math · matrix · recursion · rolling-hash · simulation · sorting · string · suffix-array · Last updated: Jun 7, 2025

Unique Length-3 Palindromic Subsequences

April 24, 2022 · 6 min · array · binary-search · binary-tree · bit-manipulation · database · depth-first-search · dynamic-programming · greedy · hash-table · leetcode · prefix-sum · string · tree · video · Last updated: Aug 2, 2025

Check if Intervals Overlap

April 22, 2022 · 1 min · interval · interviewbit · sorting · Last updated: Aug 2, 2025

Decode String

April 22, 2022 · 4 min · leetcode · recursion · stack · string · Last updated: Aug 2, 2025

Frequency of the Most Frequent Element

April 22, 2022 · 3 min · array · binary-search · database · frequency · greedy · leetcode · math · prefix-sum · sliding-window · sorting · string · two-pointers · Last updated: May 6, 2024

Run-length Encoding

April 22, 2022 · 2 min · compression · daily-coding-problem · run-length-encoding · Last updated: Aug 2, 2025

Rotate an Array to Left

April 22, 2022 · 7 min · daily-coding-problem · Last updated: Aug 2, 2025

Partition Equal Subset Sum

April 22, 2022 · 4 min · array · backtracking · daily-coding-problem · dynamic-programming · leetcode · Last updated: Aug 2, 2025

Find last position of target element in sorted array

April 22, 2022 · 2 min · divide-n-conquer · search · sorted-array · search/binary · Last updated: Aug 2, 2025

Minimum Number of Swaps to Make the String Balanced Problem

April 21, 2022 · 6 min · array · binary-indexed-tree · binary-search · database · greedy · leetcode · parentheses · stack · string · two-pointers · video · Last updated: Oct 8, 2024

Anagram Definition

April 21, 2022 · 1 min · anagram · Last updated: Aug 2, 2025

Maximum Intervals Overlap Count

April 20, 2022 · 9 min · interval · interviewbit · sorting · greedy · daily-coding-problem · Last updated: Aug 2, 2025

Linked List Cycle 4 - Delete cycle

April 20, 2022 · 5 min · linkedlist · cycle · interviewbit · Last updated: Aug 2, 2025

Find if Path Exists in Directed Graph

April 16, 2022 · 4 min · graph · graph/directed · dfs · bfs · disjoint-set · leetcode · ctci · Last updated: Aug 2, 2025

Find if Path Exists in Graph

April 16, 2022 · 4 min · bfs · binary-tree · breadth-first-search · database · depth-first-search · dfs · disjoint-set · graph · greedy · leetcode · string · tree · union-find · video · Last updated: Aug 2, 2025

Convert BST to Greater Sum Tree

April 16, 2022 · 3 min · binary-search-tree · binary-tree · bst-binary-search-tree · convert · depth-first-search · leetcode · traversal/inorder · traversal/morris · traversal/reverse-inorder · tree · video · Last updated: Aug 2, 2025

Explain x & (-x)

April 15, 2022 · 1 min · bits · Last updated: Aug 2, 2025

Palindrome Definition

April 14, 2022 · 1 min · Last updated: Jul 23, 2025

Ugly Number Definition

April 13, 2022 · 1 min · Last updated: Jul 31, 2025

Remove duplicate characters in a string

April 12, 2022 · 6 min · ctci · repeat · duplicates-algo · string · delete_remove · string-algo · Last updated: Aug 2, 2025

Check if given array is Palindrome OR Not

April 12, 2022 · 1 min · palindrome · two-pointers · Last updated: Aug 2, 2025

Expression Tree Definition

April 5, 2022 · 2 min · Last updated: Aug 2, 2025

Longest Absolute File Path

April 5, 2022 · 5 min · daily-coding-problem · depth-first-search · leetcode · map · stack · string · Last updated: Aug 2, 2025

Find index k in boolean matrix where kth row has all 0s and kth column has all 1s

April 5, 2022 · 6 min · search · binary-matrix · binary-array · Last updated: Jul 24, 2025

Sorting a Stack using push,pop,isEmpty and peek

April 5, 2022 · 7 min · ctci · stack · Last updated: Aug 2, 2025

Implement 3 stacks in 1 array

April 5, 2022 · 4 min · ctci · stack · Last updated: Aug 2, 2025

Implement insertion sort on stack

April 4, 2022 · 3 min · stack · Last updated: Aug 2, 2025

Order-agnostic Binary Search on Sorted Array

April 4, 2022 · 3 min · search/binary · Last updated: Aug 2, 2025

Unique BSTs 3 - Count given node keys between m and n

April 4, 2022 · 5 min · bst-binary-search-tree · dynamic-programming · permutation-combination · count · Last updated: Aug 2, 2025

Check if an Array of Integers is Sorted

April 3, 2022 · 4 min · recursion · array-algo · Last updated: Aug 2, 2025

Count frequency of target element in sorted array

April 3, 2022 · 2 min · frequency · sorting · search/binary · Last updated: Aug 2, 2025

Count number of bits to be flipped to convert A to B

April 3, 2022 · 2 min · array · binary-search · binary-tree · bit-manipulation · bits · combinatorics · count · counting · ctci · database · design · dynamic-programming · enumeration · graph · greedy · hash-function · hash-table · heap-priority-queue · leetcode · math · prefix-sum · rolling-hash · simulation · sorting · string · string-matching · suffix-array · tree · trie · two-pointers · xor · Last updated: Aug 2, 2025

Determine if a string has all unique characters

April 3, 2022 · 4 min · ctci · duplicates-algo · string · bits · string-algo · Last updated: Aug 2, 2025

Find floor of target element in a sorted array

April 3, 2022 · 3 min · divide-n-conquer · search · sorted-array · search/binary · floor · ceiling · Last updated: Aug 2, 2025

Find the nearest numbers that have same number of 1s for an integer

April 3, 2022 · 4 min · ctci · bits · Last updated: Aug 2, 2025

Implement selection sort on stack

April 3, 2022 · 3 min · stack · Last updated: Aug 2, 2025

List Combinations - Generate unique combinations from list selecting 1 element from each

April 3, 2022 · 2 min · backtracking · dfs · permutation-combination · Last updated: Jun 24, 2024

Longest Substring with K Distinct Characters

April 3, 2022 · 3 min · duplicates-algo · longest · substring · daily-coding-problem · sliding-window · Last updated: Aug 2, 2025

Maximum Pairwise Product 1 - Given only Positive Integers

April 3, 2022 · 2 min · product · max-min · Last updated: Aug 2, 2025

Remove duplicates from an unsorted linked list keeping only one instance

April 3, 2022 · 3 min · ctci · repeat · duplicates-algo · delete_remove · linkedlist · Last updated: Aug 2, 2025

Replace all spaces in c-style string with ‘%20’

April 3, 2022 · 3 min · ctci · string · string-algo · pattern-matching · substring · Last updated: Aug 2, 2025

Rotate String

April 3, 2022 · 3 min · ctci · daily-coding-problem · leetcode · rotate · rotated-array · string · string-algo · string-matching · Last updated: Aug 2, 2025

Set all bits of a number in a range equal to another number

April 3, 2022 · 4 min · ctci · bits · Last updated: Aug 2, 2025

Swap odd and even bits in an integer

April 3, 2022 · 4 min · ctci · bits · daily-coding-problem · Last updated: Aug 2, 2025

Find smallest letter greater than target in a sorted array of letters

April 3, 2022 · 2 min · array · binary-search · leetcode · search/binary · Last updated: Aug 2, 2025

March ³

Find Common Elements in Two Sorted Linked Lists

March 26, 2022 · 3 min · linkedlist · Last updated: Aug 2, 2025

Find last modular node in linked list for given k

March 26, 2022 · 3 min · Last updated: Aug 2, 2025

Check if the length of a linked list is even or odd

March 26, 2022 · 2 min · Last updated: Aug 2, 2025

2020 ²¹

August ²⁰

Arrays

August 10, 2020 · 1 min ·

Backtracking

August 10, 2020 · 1 min ·

Divide and Conquer

August 10, 2020 · 1 min ·

Double Linked List

August 10, 2020 · 1 min ·

Dynamic Programming

August 10, 2020 · 1 min ·

Graph

August 10, 2020 · 1 min ·

Greedy Algorithms

August 10, 2020 · 1 min ·

Hashtable

August 10, 2020 · 1 min ·

Heap

August 10, 2020 · 1 min ·

Linked List

August 10, 2020 · 1 min ·

Queue

August 10, 2020 · 1 min ·

Randomized Algorithms

August 10, 2020 · 1 min ·

Recursion

August 10, 2020 · 1 min ·

Search related Algorithms

August 10, 2020 · 1 min ·

Singly Linkedlist

August 10, 2020 · 1 min ·

Sorting Algorithms

August 10, 2020 · 1 min ·

Tree

August 10, 2020 · 1 min ·

Trie

August 10, 2020 · 1 min ·

Data Structure and Algorithm

August 5, 2020 · 0 min ·

Resume

August 5, 2020 · 1 min ·

May ¹

Array-based Trie Implementation

May 25, 2020 · 2 min · Last updated: Aug 2, 2025

2017 ⁶

April ⁵

Behavioral Cloning

April 13, 2017 · 1 min ·

Extended Kalman Filter

April 13, 2017 · 1 min ·

Kidnapped Vehicle

April 13, 2017 · 1 min ·

Traffic Sign Classifier

April 6, 2017 · 1 min ·

Vehicle Detection

April 6, 2017 · 1 min ·

January ¹

Lane Detection

January 23, 2017 · 1 min ·

2016 ⁵

December ¹

Yet another reddit app

December 21, 2016 · 1 min ·

October ³

RSS Reader

October 24, 2016 · 1 min ·

Joke Teller

October 12, 2016 · 1 min ·

Stock Hawk

October 12, 2016 · 1 min ·

March ¹

Movie Stage

March 7, 2016 · 1 min ·

2011 ²

December ¹

Stack DS to implement constant time Minimum element lookup

December 28, 2011 · 2 min · kodeknight · O(1) · CrackingTheCodingInterview · stack · min ·

September ¹

Xenon Parser

September 11, 2011 · 1 min ·

2010 ¹

January ¹

Stack implementation using linked list

January 14, 2010 · 3 min · cpp · kodeknight · link list · Data Structures · DS · linked list · cppimpl · stack · Data Structure Templates · java ·

2008 ¹

August ¹

Stack ADT

August 18, 2008 · 2 min · cpp · kodeknight · Data Structures · DS · abstract-data-type · ADT · c · parentheses · stack · Data Structure Templates · Last updated: Aug 18, 2008

2025 710

August 56

Find Largest Subset of Compatible Jobs (Interval Scheduling)

Find Largest Consecutive Integer Range in Array

Optimal Array Rounding with Sum Preservation

Distributed Wikipedia Crawler System Design

Crossword Grid Validation

Word Sense Disambiguation Algorithm

Soundex Algorithm Implementation

Ternary Search Tree Implementation

Lexicographically Smallest String with K-Position Moves

Maximum Edge Removal for Even Subtrees

Maximum Word Packing on Board

Closest pair of points

Next Bigger Integer with Same Number of 1-Bits

Uniformly Shuffle Linked List Nodes

Ways To Form Max Heap

PageRank Algorithm Implementation

Count Pairs with Given Sum and XOR

Minimum Flips to Separate X and Y

2-CNF Boolean Satisfiability Problem

Stable Marriage Problem

Implement Elo Rating System

Construct Cartesian Tree from Sequence

Minimize Maximum Mouse Distance to Holes

Approximate Median in Sub-linear Time

8-Puzzle Solver

Find Coin Denominations from Change Count

Minimum Radio Tower Broadcast Range

Find Peak in Rotated Sorted Array

Minimize Cost to Remove Gaps Between People

BST Floor and Ceiling

Bloom Filter Implementation

Election Voting Machine Monitor

Water Plant Infrastructure Optimization

Bartender Drink Optimization

Stone Pyramid Construction

Dodgeball Team Division

Qux Color Transformation

Kaprekar’s Constant Calculator

Website Similarity Analysis

Pythagorean Triplet Detection

Binary Search Without Multiplication, Division and Bit-shift Operations

Chess King Check Detector

Step Word Anagram Generator

Sentence Validation Stream Processor

Prune Unary nodes to form Full Binary Tree

Egyptian Fraction

External Sorting of integers

Three-Word Additive Cryptarithmetic Solver

Check if words chain to form a circle

Maximum of Two Numbers Without Conditionals

Prime Generator

Maximum Weight Spanning Tree

Minimum and Maximum in an array with Optimal Comparisons

Point in Polygon

Symmetric N-ary Tree Detection

Blackjack Optimal Strategy with Known Card Sequence

July 141

Minimum Insertion OR Deletion Steps to Make a String Palindrome

Minimum Deletion Steps to Make a String Palindrome

Closest Equal Element Queries

Check If Digits Are Equal in String After Operations I

Check If Digits Are Equal in String After Operations II

Choose K Elements With Maximum Sum

Concatenated Divisibility

Count Beautiful Numbers

Count Beautiful Splits in an Array

Count Cells in Overlapping Horizontal and Vertical Substrings

Count Connected Components in LCM Graph

Count Covered Buildings

Count Mentions Per User

Count Non-Decreasing Subarrays After K Operations

Count Numbers with Non-Decreasing Digits

Count Partitions with Even Sum Difference

Count Paths With the Given XOR Value

Count Special Subsequences

Count Substrings Divisible By Last Digit

Design Spreadsheet

Design Task Manager

2025 ⁷¹⁰

August ⁵⁶

July ¹⁴¹