| 001 | Two Sum | Easy | Java | |
| 002 | Add Two Numbers | Medium | Java | |
| 003 | Longest Substring Without Repeating Characters | Medium | Java | |
| 004 | Median of Two Sorted Arrays | Hard | Java | |
| 005 | Longest Palindromic Substring | Medium | Java | |
| 007 | Reverse Integer | Easy | Java | |
| 008 | String to Integer (atoi) | Medium | Java | |
| 010 | Regular Expression Matching | Hard | Java | |
| 011 | Container With Most Water | Medium | Java | |
| 013 | Roman to Integer | Easy | Java | |
| 014 | Longest Common Prefix | Easy | Java | |
| 015 | 3Sum | Medium | Java | |
| 017 | Letter Combinations of a Phone Number | Medium | Java | |
| 019 | Remove Nth Node From End of List | Easy | Java | |
| 020 | Valid Parentheses | Easy | Java | |
| 021 | Merge Two Sorted Lists | Easy | Java | |
| 022 | Generate Parentheses | Medium | Java | |
| 023 | Merge k Sorted Lists | Hard | Java | |
| 026 | Remove Duplicates from Sorted Array | Easy | Java | |
| 028 | Implement strStr() | Easy | Java | |
| 029 | Divide Two Integers | Medium | Java | |
| 033 | Search in Rotated Sorted Array | Medium | Java | |
| 034 | Search for a Range | Medium | Java | |
| 035 | Search Insert Position | Medium | Java | |
| 036 | Valid Sudoku | Medium | Java | |
| 038 | Count and Say | Easy | Java | |
| 041 | First Missing Positive | Hard | Java | |
| 042 | Trapping Rain Water | Hard | Java | |
| 044 | Wildcard Matching | Hard | Java | |
| 046 | Permutations | Medium | Java | |
| 048 | Rotate Image | Medium | Java | |
| 049 | Group Anagrams | Medium | Java | |
| 050 | Pow(x, n) | Medium | Java | |
| 053 | Maximum Subarray | Medium | Java | |
| 054 | Spiral Matrix | Medium | Java | |
| 055 | Jump Game | Medium | Java | |
| 056 | Merge Intervals | Medium | Java | |
| 062 | Unique Paths | Medium | Java | |
| 066 | Plus One | Easy | Java | |
| 069 | Sqrt(x) | Easy | Java | |
| 070 | Climbing Stairs | Easy | Java | |
| 073 | Set Matrix Zeroes | Medium | Java | |
| 075 | Sort Colors | Medium | Java | |
| 076 | Minimum Window Substring | Hard | Java | |
| 078 | Subsets | Medium | Java | |
| 079 | Word Search | Medium | Java | |
| 084 | Largest Rectangle in Histogram | Hard | Java | |
| 088 | Merge Sorted Array | Easy | Java | |
| 091 | Decode Ways | Medium | Java | |
| 094 | Binary Tree Inorder Traversal | Medium | Java | |
| 098 | Validate Binary Search Tree | Medium | Java | |
| 101 | Symmetric Tree | Easy | Java | |
| 102 | Binary Tree Level Order Traversal | Easy | Java | |
| 103 | Binary Tree Zigzag Level Order Traversal | Medium | Java | |
| 104 | Maximum Depth of Binary Tree | Easy | Java | |
| 105 | Construct Binary Tree from Preorder and Inorder Traversal | Medium | Java | |
| 108 | Convert Sorted Array to Binary Search Tree | Easy | Java | |
| 116 | Populating Next Right Pointers in Each Node | Medium | Java | |
| 118 | Pascal’s Triangle | Easy | Java | |
| 121 | Best Time to Buy and Sell Stock | Easy | Java | |
| 122 | Best Time to Buy and Sell Stock II | Easy | Java | |
| 124 | Binary Tree Maximum Path Sum | Hard | Java | |
| 125 | Valid Palindrome | Easy | Java | |
| 127 | Word Ladder | Medium | Java | |
| 128 | Longest Consecutive Sequence | Hard | Java | |
| 130 | Surrounded Regions | Medium | Java | |
| 131 | Palindrome Partitioning | Medium | Java | |
| 134 | Gas Station | Medium | Java | |
| 136 | Single Number | Easy | Java | |
| 138 | Copy List with Random Pointer | Medium | Java | |
| 139 | Word Break | Medium | Java | |
| 140 | Word Break II | Hard | Java | |
| 141 | Linked List Cycle | Easy | Java | |
| 146 | LRU Cache | Hard | Java | |
| 148 | Sort List | Medium | Java | |
| 149 | Max Points on a Line | Hard | Java | |
| 150 | Evaluate Reverse Polish Notation | Medium | Java | |
| 152 | Maximum Product Subarray | Medium | Java | |
| 155 | Min Stack | Easy | Java | |
| 160 | Intersection of Two Linked Lists | Easy | Java | |
| 162 | Find Peak Element | Medium | Java | |
| 163 | Missing Ranges | Medium | [没权限] | |
| 166 | Fraction to Recurring Decimal | Medium | Java | |
| 169 | Majority Element | Easy | Java | |
| 171 | Excel Sheet Column Number | Easy | Java | |
| 172 | Factorial Trailing Zeroes | Easy | Java | |
| 179 | Largest Number | Medium | Java | |
| 189 | Rotate Array | Easy | Java | |
| 190 | Reverse Bits | Easy | Java | |
| 191 | Number of 1 Bits | Easy | Java | |
| 198 | House Robber | Easy | Java | |
| 200 | Number of Islands | Medium | Java | |
| 202 | Happy Number | Easy | Java | |
| 204 | Count Primes | Easy | Java | |
| 206 | Reverse Linked List | Easy | Java | |
| 207 | Course Schedule | Medium | Java | |
| 208 | Implement Trie (Prefix Tree) | Medium | Java | |
| 210 | Course Schedule II | Medium | Java | |
| 212 | Word Search II | Hard | Java | |
| 215 | Kth Largest Element in an Array | Medium | Java | |
| 217 | Contains Duplicate | Easy | Java | |
| 218 | The Skyline Problem | Hard | Java | |
| 227 | Basic Calculator II | Medium | Java | |
| 230 | Kth Smallest Element in a BST | Medium | Java | |
| 234 | Palindrome Linked List | Easy | Java | |
| 236 | Lowest Common Ancestor of a Binary Tree | Medium | Java | |
| 237 | Delete Node in a Linked List | Easy | Java | |
| 238 | Product of Array Except Self | Medium | Java | |
| 239 | Sliding Window Maximum | Hard | Java | |
| 240 | Search a 2D Matrix II | Medium | Java | |
| 242 | Valid Anagram | Easy | Java | |
| 251 | Flatten 2D Vector | Medium | [没权限] | |
| 253 | Meeting Rooms II | Medium | [没权限] | |
| 268 | Missing Number | Easy | Java | |
| 269 | Alien Dictionary | Hard | [没权限] | |
| 277 | Find the Celebrity | Medium | [没权限] | |
| 279 | Perfect Squares | Medium | Java | |
| 283 | Move Zeroes | Easy | Java | |
| 285 | Inorder Successor in BST | Medium | [没权限] | |
| 287 | Find the Duplicate Number | Hard | Java | |
| 295 | Find Median from Data Stream | Hard | Java | |
| 297 | Serialize and Deserialize Binary Tree | Hard | Java | |
| 300 | Longest Increasing Subsequence | Medium | Java | |
| 308 | Range Sum Query 2D - Mutable | Medium | [没权限] | |
| 315 | Count of Smaller Numbers After Self | Hard | Java | |
| 322 | Coin Change | Medium | Java | |
| 324 | Wiggle Sort II | Medium | Java | |
| 326 | Power of Three | Easy | Java | |
| 328 | Odd Even Linked List | Medium | Java | |
| 329 | Longest Increasing Path in a Matrix | Hard | Java | |
| 334 | Increasing Triplet Subsequence | Medium | Java | |
| 340 | Longest Substring with At Most K Distinct Characters | Hard | [Plus] | |
| 341 | Flatten Nested List Iterator | Medium | Java | |
| 344 | Reverse String | Easy | Java | |
| 347 | Top K Frequent Elements | Medium | Java | |
| 348 | Design Tic-Tac-Toe | Medium | [没权限] | |
| 350 | Intersection of Two Arrays II | Easy | Java | |
| 371 | Sum of Two Integers | Medium | Java | |
| 378 | Kth Smallest Element in a Sorted Matrix | Medium | Java | |
| 380 | Insert Delete GetRandom O(1) | Medium | Java | |
| 384 | Shuffle an Array | Medium | Java | |
| 387 | First Unique Character in a String | Easy | Java | |
| 395 | Longest Substring with At Least K Repeating Characters | Medium | Java | |
| 412 | Fizz Buzz | Easy | Java | |
| 454 | 4Sum II | Medium | Java | |