Tags

Below is a list of problems classified by tags, suitable for focused practice on a certain type of problem.

Array

• 1. Two Sum
• 4. Median of Two Sorted Arrays
• 11. Container With Most Water
• 15. 3Sum
• 16. 3Sum Closest
• 18. 4Sum
• 26. Remove Duplicates from Sorted Array
• 27. Remove Element
• 31. Next Permutation
• 33. Search in Rotated Sorted Array
• 34. Find First and Last Position of Element in Sorted Array
• 35. Search Insert Position
• 36. Valid Sudoku
• 37. Sudoku Solver
• 39. Combination Sum
• 40. Combination Sum II
• 41. First Missing Positive
• 42. Trapping Rain Water
• 45. Jump Game II
• 46. Permutations
• 47. Permutations II
• 48. Rotate Image
• 49. Group Anagrams
• 51. N-Queens
• 53. Maximum Subarray
• 54. Spiral Matrix
• 55. Jump Game
• 56. Merge Intervals
• 57. Insert Interval
• 59. Spiral Matrix II
• 63. Unique Paths II
• 64. Minimum Path Sum
• 66. Plus One
• 68. Text Justification
• 73. Set Matrix Zeroes
• 74. Search a 2D Matrix
• 75. Sort Colors
• 78. Subsets
• 79. Word Search
• 80. Remove Duplicates from Sorted Array II
• 81. Search in Rotated Sorted Array II
• 84. Largest Rectangle in Histogram
• 85. Maximal Rectangle
• 88. Merge Sorted Array
• 90. Subsets II
• 105. Construct Binary Tree from Preorder and Inorder Traversal
• 106. Construct Binary Tree from Inorder and Postorder Traversal
• 108. Convert Sorted Array to Binary Search Tree
• 118. Pascal's Triangle
• 119. Pascal's Triangle II
• 120. Triangle
• 121. Best Time to Buy and Sell Stock
• 122. Best Time to Buy and Sell Stock II
• 123. Best Time to Buy and Sell Stock III
• 128. Longest Consecutive Sequence
• 130. Surrounded Regions
• 134. Gas Station
• 135. Candy
• 136. Single Number
• 137. Single Number II
• 139. Word Break
• 140. Word Break II
• 149. Max Points on a Line
• 150. Evaluate Reverse Polish Notation
• 152. Maximum Product Subarray
• 153. Find Minimum in Rotated Sorted Array
• 154. Find Minimum in Rotated Sorted Array II
• 157. Read N Characters Given Read4 🔒
• 158. Read N Characters Given read4 II - Call Multiple Times 🔒
• 162. Find Peak Element
• 163. Missing Ranges 🔒
• 164. Maximum Gap
• 167. Two Sum II - Input Array Is Sorted
• 169. Majority Element
• 170. Two Sum III - Data structure design 🔒
• 174. Dungeon Game
• 179. Largest Number
• 188. Best Time to Buy and Sell Stock IV
• 189. Rotate Array
• 198. House Robber
• 200. Number of Islands
• 204. Count Primes
• 209. Minimum Size Subarray Sum
• 212. Word Search II
• 213. House Robber II
• 215. Kth Largest Element in an Array
• 216. Combination Sum III
• 217. Contains Duplicate
• 218. The Skyline Problem
• 219. Contains Duplicate II
• 220. Contains Duplicate III
• 221. Maximal Square
• 228. Summary Ranges
• 229. Majority Element II
• 238. Product of Array Except Self
• 239. Sliding Window Maximum
• 240. Search a 2D Matrix II
• 243. Shortest Word Distance 🔒
• 244. Shortest Word Distance II 🔒
• 245. Shortest Word Distance III 🔒
• 247. Strobogrammatic Number II 🔒
• 248. Strobogrammatic Number III 🔒
• 249. Group Shifted Strings 🔒
• 251. Flatten 2D Vector 🔒
• 252. Meeting Rooms 🔒
• 253. Meeting Rooms II 🔒
• 255. Verify Preorder Sequence in Binary Search Tree 🔒
• 256. Paint House 🔒
• 259. 3Sum Smaller 🔒
• 260. Single Number III
• 265. Paint House II 🔒
• 268. Missing Number
• 269. Alien Dictionary 🔒
• 271. Encode and Decode Strings 🔒
• 274. H-Index
• 275. H-Index II
• 280. Wiggle Sort 🔒
• 281. Zigzag Iterator 🔒
• 283. Move Zeroes
• 284. Peeking Iterator
• 286. Walls and Gates 🔒
• 287. Find the Duplicate Number
• 288. Unique Word Abbreviation 🔒
• 289. Game of Life
• 296. Best Mee