* multiple solutions
- 6. Zigzag Conversion
- 14. Longest Common Prefix
- 26. Remove Duplicates from Sorted Array
- 27. Remove Element
- 28. Find the Index of the First Occurrence in a String
- 42. Trapping Rain Water
- 45. Jump Game II
- 55. Jump Game
- 58. Length of Last Word
- 68. Text Justification
- 80. Remove Duplicates from Sorted Array II
- 88. Merge Sorted Array
- 121. Best Time to Buy and Sell Stock
- 122. Best Time to Buy and Sell Stock II
- 134. Gas Station
- 135. Candy
- 151. Reverse Words in a String
- 169. Majority Element
- 189. Rotate Array
- 238. Product of Array Except Self
- 274. H-Index
- 350. Intersection of Two Arrays II
- 380. Insert Delete GetRandom O(1)
- 796. Rotate String
- 912. Sort an Array #counting-sort
- 1380. Lucky Numbers in a Matrix
- 1605. Find Valid Matrix Given Row and Column Sums
- 1636. Sort Array by Increasing Frequency
- 1653. Minimum Deletions to Make String Balanced
- 2053. Kth Distinct String in an Array
- 2191. Sort the Jumbled Numbers
- 2418. Sort the People
- 2678. Number of Senior Citizens
- 3. Longest Substring Without Repeating Characters
- 30. Substring with Concatenation of All Words
- 209. Minimum Size Subarray Sum
- 11. Container With Most Water
- 15. 3Sum
- 125. Valid Palindrome
- 167. Two Sum II - Input Array Is Sorted
- 392. Is Subsequence
- 1105. Filling Bookcase Shelves
- 1395. Count Number of Teams
- 22. Generate Parentheses #backtracking
- 46. Permutations #backtracking
- 1334. Find the City With the Smallest Number of Neighbors at a Threshold Distance #shortest-path
- 2045. Second Minimum Time to Reach Destination* #shortest-path #bfs #dijkstra
- 2976. Minimum Cost to Convert String I #shortest-path
- 2. Add Two Numbers
- 19. Remove Nth Node From End of List
- 82. Remove Duplicates from Sorted List II
- 83. Remove Duplicates from Sorted List
- 86. Partition List
- 141. Linked List Cycle 2095. Delete the Middle Node of a Linked List
- 1. Two Sum
- 12. Integer to Roman
- 13. Roman to Integer
- 205. Isomorphic Strings
- 383. Ransom Note
- 1460. Make Two Arrays Equal by Reversing Subarrays
- 726. Number of Atoms*
- 1190. Reverse Substrings Between Each Pair of Parentheses
- 1509. Minimum Difference Between Largest and Smallest Value in Three Moves
- 1518. Water Bottles
- 1598. Crawler Log Folder
- 1701. Average Waiting Time
- 1717. Maximum Score From Removing Substrings
- 1823. Find the Winner of the Circular Game
- 2058. Find the Minimum and Maximum Number of Nodes Between Critical Points
- 2096. Step-By-Step Directions From a Binary Tree Node to Another
- 2134. Minimum Swaps to Group All 1's Together II #sliding-window
- 2196. Create Binary Tree From Descriptions
- 2582. Pass the Pillow
- 2751. Robot Collisions
- 3136. Valid Word