Array (10)
TitleDifficultyVideos
Two Sum Easy
Best Time To Buy And Sell Stock 1 - only one transaction Easy
Contains Duplicate 1 - Check if array has duplicates Easy
Container With Most Water Medium
3Sum0 - Find three elements in an array that sum to a zero Medium
Search in Rotated Sorted Array Medium
Maximum Subarray Sum Medium
Maximum Product Subarray Medium
Find Minimum in Rotated Sorted Array 1 - No duplicates allowed Medium
Product of Array Except Self Medium
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Bit manipulation (5)
TitleDifficultyVideos
Reverse Bits Easy
Number of 1 Bits Easy
Missing Number Easy
Counting Bits Easy
Sum of Two Integers Medium
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Dynamic programming (11)
TitleDifficultyVideos
Climbing Stairs 1 - Take atmost 2 Steps Easy
Combination Sum 1 Medium
Jump Game 1 - Check if it reaches last index Medium
Unique Paths in Grid 1 - Count all paths moving right or down Medium
Decode Ways Medium
Word Break 1 - Check if word is breakable Medium
House Robber Medium
House Robber 2 - Houses in circle Medium
Longest Increasing Subsequence LIS Medium
Coin Change with Fewest Number of Coins Given Infinite Supply Medium
Longest Common Subsequence LCS 1 - Get Length Medium
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Graph (8)
TitleDifficultyVideos
Longest Consecutive Sequence Medium
Clone Undirected Graph Medium
Number of Islands Medium
Course Schedule 1 - Is it Possible Medium
Graph Valid Tree Medium
Number of Connected Components in an Undirected Graph Medium
Pacific Atlantic Water Flow Medium
Alien Dictionary Hard
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Interval (5)
TitleDifficultyVideos
Meeting Rooms 1 - Can person attend all meetings Easy
Merge Overlapping Intervals Medium
Insert Interval Medium
Meeting Rooms 2 - Minimum Meeting Rooms Required Medium
Non-overlapping Intervals Medium
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Linked list (6)
TitleDifficultyVideos
Merge Two Sorted Linked Lists Easy
Linked List Cycle 1 - Detect Cycle Easy
Reverse Linked List Easy
Remove Nth Node From End of List Medium
Reorder List such that i-th element points to n-i th element Medium
Merge K Sorted Lists Hard
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Matrix (4)
TitleDifficultyVideos
Rotate n x n matrix by 90 degrees Medium
Spiral Matrix 1 - Return Medium
Set Matrix Zeros Medium
Word Search 1 - Find if word exists Medium
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String (10)
TitleDifficultyVideos
Valid Parentheses Easy
Valid Palindrome Easy
Valid Anagram Easy
Longest Substring Without Repeating Characters Medium
Longest Palindromic Substring Medium
Group Anagrams Medium
Encode and Decode Strings Medium
Longest Substring with Same Letters after Replacement Medium
Palindromic Substrings Medium
Minimum Window Substring Hard
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Tree (14)
TitleDifficultyVideos
Same Tree Easy
Maximum Depth of Binary Tree Easy
Invert Binary Tree Easy
Subtree of Another Tree Easy
Validate Binary Search Tree Medium
Binary Tree Level Order Traversal - Level by Level Medium
Construct Binary Tree from Inorder and Preorder Traversal Medium
Implement Trie Medium
Design Add and Search Words Data Structure Medium
Kth Smallest Element in a BST Medium
Lowest Common Ancestor of a Binary Search Tree Medium
Binary Tree Path Sum - Maximum between any two nodes Hard
Word Search 2 - Return All Words Hard
Serialize and Deserialize Binary Tree Hard
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Heap priority queue (2)
TitleDifficultyVideos
Top K Frequent Elements Medium
Find Median from Data Stream Hard