| Construct K Palindrome Strings |
Medium
|
uber
|
|
| Find Missing 1000 Numbers in Large Range |
Medium
|
two sigma
|
|
| Explaining Web Cookies to Non-Technical Person |
Medium
|
airtable
|
|
| Explaining API vs SDK to Non-Technical Person |
Medium
|
amazon
|
|
| Decrypt XOR-Encoded Hexadecimal String |
Medium
|
apple
|
|
| Decode Base64 String to Hex |
Easy
|
google
|
|
| Convert Hex String to Base64 |
Easy
|
paypal
|
|
| Find Closest Coin by Manhattan Distance |
Easy
|
google
|
|
| Count Digits Without Loops |
Easy
|
amazon
|
|
| Solve System of Linear Addition Equations |
Hard
|
google
|
|
| Calculate Courier Active Time from Event Logs |
Easy
|
postmates
|
|
| Key-Value Store with Max Key Query |
Hard
|
google
|
|
| Merge Two Sorted Iterators |
Medium
|
two-sigma
|
|
| Implement Quack Data Structure with Three Stacks |
Hard
|
google
|
|
| Alternating Add-Subtract Curried Function |
Medium
|
|
|
| Validate Mastermind Game Guesses |
Medium
|
facebook
|
|
| Interleave Ranked Song Lists for Playlist |
Medium
|
spotify
|
|
| Reconstruct Numbers from Anagrammed String |
Easy
|
slack
|
|
| Binary Tree Depth from Parenthesized String Representation |
Hard
|
linkedin
|
|
| Queue using Set of Fixed-Length Arrays |
Hard
|
netflix
|
|
| Word Subsets |
Medium
|
amazon
facebook
google
|
|
| Nearest larger number for index in an array |
Medium
|
google
|
|
| Counting Words With a Given Prefix |
Easy
|
|
|
| Implement 3 stacks in 1 list |
Hard
|
microsoft
|
|
| Implement a bit array |
Medium
|
amazon
|
|
| Count Prefix and Suffix Pairs I |
Easy
|
|
|
| Design a Sparse Array |
Easy
|
facebook
|
|
| String Matching in an Array |
Easy
|
amazon
|
|
| Minimum Number of Operations to Move All Balls to Each Box |
Medium
|
|
|
| Design hit counter with range queries |
Easy
|
riot-games
|
|
| Square root of a real number |
Medium
|
|
|
| Shifting Letters II |
Medium
|
|
|
| Check if target word exists in matrix horizontally or vertically |
Easy
|
microsoft
|
|
| Break a string into lines of length k without breaking words |
Medium
|
amazon
|
|
| Expected number of rounds to reach one remaining coin |
Easy
|
microsoft
|
|
| Maximum coins from top-left to bottom-right with right or down moves |
Medium
|
zillow
|
|
| Smallest set to cover all intervals |
Medium
|
google
microsoft
|
|
| Number of Ways to Split Array |
Medium
|
|
|
| Generate a finite, but an arbitrarily large binary tree in O(1) time |
Medium
|
jane-street
|
|
| Find all starting indices of anagrams of a word in a string |
Hard
|
|
|
| Count Vowel Strings in Ranges |
Medium
|
|
|
| Best Sightseeing Pair |
Medium
|
wayfair
|
|
| Find Largest Value in Each Tree Row |
Medium
|
amazon
apple
facebook
linkedin
microsoft
|
|
| Check if doubly linked list is palindrome |
Easy
|
google
|
|
| Shortest substring containing all characters in a set |
Medium
|
square
|
|
| Return two prime numbers that sum to a given even number |
Easy
|
alibaba
|
|
| Find Minimum Diameter After Merging Two Trees |
Hard
|
|
|
| Minimum Number of Operations to Sort a Binary Tree by Level |
Medium
|
|
|
| Maximum Number of K-Divisible Components |
Hard
|
|
|
| Reverse Odd Levels of Binary Tree |
Medium
|
|
|