Until 2018-05-28 11:58:16, I have solved 99 / 758 problems while 133 are still locked.
Completion statistic:
- JavaScript: 59
- Python: 49
- C++: 1
- Java: 1
Note: 🔒 means you need to buy a book from LeetCode
| ID | Title | Difficulty | JavaScript | Python | C++ | Java |
|---|---|---|---|---|---|---|
| 001 | Two Sum | Easy | JavaScript | Python | C++ | Java |
| 002 | Add Two Numbers | Medium | JavaScript | Python | To Do | To Do |
| 003 | Longest Substring Without Repeating Characters | Medium | To Do | Python | To Do | To Do |
| 004 | Median of Two Sorted Arrays | Hard | JavaScript | Python | To Do | To Do |
| 005 | Longest Palindromic Substring | Medium | To Do | Python | To Do | To Do |
| 006 | ZigZag Conversion | Medium | To Do | Python | To Do | To Do |
| 007 | Reverse Integer | Easy | JavaScript | Python | To Do | To Do |
| 008 | String to Integer (atoi) | Medium | To Do | To Do | To Do | To Do |
| 009 | Palindrome Number | Easy | To Do | Python | To Do | To Do |
| 010 | Regular Expression Matching | Hard | To Do | To Do | To Do | To Do |
| 011 | Container With Most Water | Medium | JavaScript | To Do | To Do | To Do |
| 012 | Integer to Roman | Medium | To Do | Python | To Do | To Do |
| 013 | Roman to Integer | Easy | JavaScript | Python | To Do | To Do |
| 014 | Longest Common Prefix | Easy | JavaScript | Python | To Do | To Do |
| 015 | 3Sum | Medium | JavaScript | Python | To Do | To Do |
| 016 | 3Sum Closest | Medium | JavaScript | To Do | To Do | To Do |
| 017 | Letter Combinations of a Phone Number | Medium | To Do | Python | To Do | To Do |
| 018 | 4Sum | Medium | JavaScript | To Do | To Do | To Do |
| 019 | Remove Nth Node From End of List | Medium | To Do | To Do | To Do | To Do |
| 020 | Valid Parentheses | Easy | JavaScript | Python | To Do | To Do |
| 021 | Merge Two Sorted Lists | Easy | JavaScript | To Do | To Do | To Do |
| 022 | Generate Parentheses | Medium | To Do | To Do | To Do | To Do |
| 023 | Merge k Sorted Lists | Hard | To Do | To Do | To Do | To Do |
| 024 | Swap Nodes in Pairs | Medium | To Do | To Do | To Do | To Do |
| 025 | Reverse Nodes in k-Group | Hard | To Do | To Do | To Do | To Do |
| 026 | Remove Duplicates from Sorted Array | Easy | JavaScript | To Do | To Do | To Do |
| 027 | Remove Element | Easy | JavaScript | To Do | To Do | To Do |
| 028 | Implement strStr() | Easy | JavaScript | To Do | To Do | To Do |
| 029 | Divide Two Integers | Medium | To Do | To Do | To Do | To Do |
| 030 | Substring with Concatenation of All Words | Hard | To Do | To Do | To Do | To Do |
| 031 | Next Permutation | Medium | JavaScript | To Do | To Do | To Do |
| 032 | Longest Valid Parentheses | Hard | To Do | To Do | To Do | To Do |
| 033 | Search in Rotated Sorted Array | Medium | JavaScript | To Do | To Do | To Do |
| 034 | Search for a Range | Medium | JavaScript | To Do | To Do | To Do |
| 035 | Search Insert Position | Easy | JavaScript | To Do | To Do | To Do |
| 036 | Valid Sudoku | Medium | To Do | To Do | To Do | To Do |
| 037 | Sudoku Solver | Hard | To Do | To Do | To Do | To Do |
| 038 | Count and Say | Easy | To Do | Python | To Do | To Do |
| 039 | Combination Sum | Medium | JavaScript | To Do | To Do | To Do |
| 040 | Combination Sum II | Medium | JavaScript | To Do | To Do | To Do |
| 041 | First Missing Positive | Hard | JavaScript | To Do | To Do | To Do |
| 042 | Trapping Rain Water | Hard | To Do | To Do | To Do | To Do |
| 043 | Multiply Strings | Medium | To Do | Python | To Do | To Do |
| 044 | Wildcard Matching | Hard | To Do | To Do | To Do | To Do |
| 045 | Jump Game II | Hard | To Do | To Do | To Do | To Do |
| 046 | Permutations | Medium | To Do | To Do | To Do | To Do |
| 047 | Permutations II | Medium | To Do | To Do | To Do | To Do |
| 048 | Rotate Image | Medium | JavaScript | Python | To Do | To Do |
| 049 | Group Anagrams | Medium | To Do | To Do | To Do | To Do |
| 050 | Pow(x, n) | Medium | JavaScript | To Do | To Do | To Do |
| 051 | N-Queens | Hard | To Do | To Do | To Do | To Do |
| 052 | N-Queens II | Hard | To Do | To Do | To Do | To Do |
| 053 | Maximum Subarray | Easy | JavaScript | To Do | To Do | To Do |
| 054 | Spiral Matrix | Medium | JavaScript | To Do | To Do | To Do |
| 055 | Jump Game | Medium | JavaScript | To Do | To Do | To Do |
| 056 | Merge Intervals | Medium | To Do | To Do | To Do | To Do |
| 057 | Insert Interval | Hard | To Do | To Do | To Do | To Do |
| 058 | Length of Last Word | Easy | To Do | Python | To Do | To Do |
| 059 | Spiral Matrix II | Medium | JavaScript | To Do | To Do | To Do |
| 060 | Permutation Sequence | Medium | To Do | To Do | To Do | To Do |
| 061 | Rotate List | Medium | To Do | To Do | To Do | To Do |
| 062 | Unique Paths | Medium | To Do | To Do | To Do | To Do |
| 063 | Unique Paths II | Medium | To Do | To Do | To Do | To Do |
| 064 | Minimum Path Sum | Medium | To Do | To Do | To Do | To Do |
| 065 | Valid Number | Hard | To Do | To Do | To Do | To Do |
| 066 | Plus One | Easy | JavaScript | To Do | To Do | To Do |
| 067 | Add Binary | Easy | JavaScript | To Do | To Do | To Do |
| 068 | Text Justification | Hard | To Do | To Do | To Do | To Do |
| 069 | Sqrt(x) | Easy | JavaScript | To Do | To Do | To Do |
| 070 | Climbing Stairs | Easy | To Do | Python | To Do | To Do |
| 071 | Simplify Path | Medium | To Do | To Do | To Do | To Do |
| 072 | Edit Distance | Hard | To Do | To Do | To Do | To Do |
| 073 | Set Matrix Zeroes | Medium | To Do | To Do | To Do | To Do |
| 074 | Search a 2D Matrix | Medium | To Do | To Do | To Do | To Do |
| 075 | Sort Colors | Medium | To Do | To Do | To Do | To Do |
| 076 | Minimum Window Substring | Hard | To Do | To Do | To Do | To Do |
| 077 | Combinations | Medium | To Do | To Do | To Do | To Do |
| 078 | Subsets | Medium | To Do | To Do | To Do | To Do |
| 079 | Word Search | Medium | To Do | To Do | To Do | To Do |
| 080 | Remove Duplicates from Sorted Array II | Medium | To Do | To Do | To Do | To Do |
| 081 | Search in Rotated Sorted Array II | Medium | To Do | To Do | To Do | To Do |
| 082 | Remove Duplicates from Sorted List II | Medium | To Do | To Do | To Do | To Do |
| 083 | Remove Duplicates from Sorted List | Easy | JavaScript | To Do | To Do | To Do |
| 084 | Largest Rectangle in Histogram | Hard | JavaScript | To Do | To Do | To Do |
| 085 | Maximal Rectangle | Hard | To Do | To Do | To Do | To Do |
| 086 | Partition List | Medium | To Do | To Do | To Do | To Do |
| 087 | Scramble String | Hard | To Do | To Do | To Do | To Do |
| 088 | Merge Sorted Array | Easy | JavaScript | To Do | To Do | To Do |
| 089 | Gray Code | Medium | To Do | To Do | To Do | To Do |
| 090 | Subsets II | Medium | To Do | To Do | To Do | To Do |
| 091 | Decode Ways | Medium | To Do | To Do | To Do | To Do |
| 092 | Reverse Linked List II | Medium | To Do | Python | To Do | To Do |
| 093 | Restore IP Addresses | Medium | To Do | To Do | To Do | To Do |
| 094 | Binary Tree Inorder Traversal | Medium | To Do | To Do | To Do | To Do |
| 095 | Unique Binary Search Trees II | Medium | To Do | To Do | To Do | To Do |
| 096 | Unique Binary Search Trees | Medium | To Do | To Do | To Do | To Do |
| 097 | Interleaving String | Hard | To Do | To Do | To Do | To Do |
| 098 | Validate Binary Search Tree | Medium | To Do | To Do | To Do | To Do |
| 099 | Recover Binary Search Tree | Hard | To Do | To Do | To Do | To Do |
| 100 | Same Tree | Easy | JavaScript | To Do | To Do | To Do |
| 101 | Symmetric Tree | Easy | JavaScript | To Do | To Do | To Do |
| 102 | Binary Tree Level Order Traversal | Medium | To Do | Python | To Do | To Do |
| 103 | Binary Tree Zigzag Level Order Traversal | Medium | To Do | To Do | To Do | To Do |
| 104 | Maximum Depth of Binary Tree | Easy | To Do | Python | To Do | To Do |
| 105 | Construct Binary Tree from Preorder and Inorder Traversal | Medium | To Do | To Do | To Do | To Do |
| 106 | Construct Binary Tree from Inorder and Postorder Traversal | Medium | To Do | To Do | To Do | To Do |
| 107 | Binary Tree Level Order Traversal II | Easy | To Do | Python | To Do | To Do |
| 108 | Convert Sorted Array to Binary Search Tree | Easy | To Do | Python | To Do | To Do |
| 109 | Convert Sorted List to Binary Search Tree | Medium | To Do | To Do | To Do | To Do |
| 110 | Balanced Binary Tree | Easy | To Do | Python | To Do | To Do |
| 111 | Minimum Depth of Binary Tree | Easy | To Do | Python | To Do | To Do |
| 112 | Path Sum | Easy | To Do | Python | To Do | To Do |
| 113 | Path Sum II | Medium | To Do | To Do | To Do | To Do |
| 114 | Flatten Binary Tree to Linked List | Medium | To Do | To Do | To Do | To Do |
| 115 | Distinct Subsequences | Hard | To Do | To Do | To Do | To Do |
| 116 | Populating Next Right Pointers in Each Node | Medium | To Do | To Do | To Do | To Do |
| 117 | Populating Next Right Pointers in Each Node II | Medium | To Do | To Do | To Do | To Do |
| 118 | Pascal's Triangle | Easy | To Do | Python | To Do | To Do |
| 119 | Pascal's Triangle II | Easy | To Do | Python | To Do | To Do |
| 120 | Triangle | Medium | To Do | To Do | To Do | To Do |
| 121 | Best Time to Buy and Sell Stock | Easy | JavaScript | To Do | To Do | To Do |
| 122 | Best Time to Buy and Sell Stock II | Easy | JavaScript | To Do | To Do | To Do |
| 123 | Best Time to Buy and Sell Stock III | Hard | JavaScript | To Do | To Do | To Do |
| 124 | Binary Tree Maximum Path Sum | Hard | To Do | To Do | To Do | To Do |
| 125 | Valid Palindrome | Easy | To Do | Python | To Do | To Do |
| 126 | Word Ladder II | Hard | To Do | To Do | To Do | To Do |
| 127 | Word Ladder | Medium | To Do | To Do | To Do | To Do |
| 128 | Longest Consecutive Sequence | Hard | To Do | To Do | To Do | To Do |
| 129 | Sum Root to Leaf Numbers | Medium | To Do | To Do | To Do | To Do |
| 130 | Surrounded Regions | Medium | To Do | To Do | To Do | To Do |
| 131 | Palindrome Partitioning | Medium | To Do | To Do | To Do | To Do |
| 132 | Palindrome Partitioning II | Hard | To Do | To Do | To Do | To Do |
| 133 | Clone Graph | Medium | To Do | To Do | To Do | To Do |
| 134 | Gas Station | Medium | To Do | To Do | To Do | To Do |
| 135 | Candy | Hard | To Do | To Do | To Do | To Do |
| 136 | Single Number | Easy | JavaScript | To Do | To Do | To Do |
| 137 | Single Number II | Medium | JavaScript | To Do | To Do | To Do |
| 138 | Copy List with Random Pointer | Medium | To Do | To Do | To Do | To Do |
| 139 | Word Break | Medium | To Do | To Do | To Do | To Do |
| 140 | Word Break II | Hard | To Do | To Do | To Do | To Do |
| 141 | Linked List Cycle | Easy | To Do | Python | To Do | To Do |
| 142 | Linked List Cycle II | Medium | To Do | To Do | To Do | To Do |
| 143 | Reorder List | Medium | To Do | To Do | To Do | To Do |
| 144 | Binary Tree Preorder Traversal | Medium | To Do | To Do | To Do | To Do |
| 145 | Binary Tree Postorder Traversal | Hard | To Do | To Do | To Do | To Do |
| 146 | LRU Cache | Hard | To Do | To Do | To Do | To Do |
| 147 | Insertion Sort List | Medium | To Do | To Do | To Do | To Do |
| 148 | Sort List | Medium | To Do | To Do | To Do | To Do |
| 149 | Max Points on a Line | Hard | To Do | To Do | To Do | To Do |
| 150 | Evaluate Reverse Polish Notation | Medium | To Do | To Do | To Do | To Do |
| 151 | Reverse Words in a String | Medium | To Do | To Do | To Do | To Do |
| 152 | Maximum Product Subarray | Medium | To Do | To Do | To Do | To Do |
| 153 | Find Minimum in Rotated Sorted Array | Medium | To Do | To Do | To Do | To Do |
| 154 | Find Minimum in Rotated Sorted Array II | Hard | To Do | To Do | To Do | To Do |
| 155 | Min Stack | Easy | To Do | Python | To Do | To Do |
| 156 | Binary Tree Upside Down 🔒 | Medium | To Do | To Do | To Do | To Do |
| 157 | Read N Characters Given Read4 🔒 | Easy | To Do | To Do | To Do | To Do |
| 158 | Read N Characters Given Read4 II - Call multiple times 🔒 | Hard | To Do | To Do | To Do | To Do |
| 159 | Longest Substring with At Most Two Distinct Characters 🔒 | Hard | To Do | To Do | To Do | To Do |
| 160 | Intersection of Two Linked Lists | Easy | To Do | Python | To Do | To Do |
| 161 | One Edit Distance 🔒 | Medium | To Do | To Do | To Do | To Do |
| 162 | Find Peak Element | Medium | To Do | To Do | To Do | To Do |
| 163 | Missing Ranges 🔒 | Medium | To Do | To Do | To Do | To Do |
| 164 | Maximum Gap | Hard | To Do | To Do | To Do | To Do |
| 165 | Compare Version Numbers | Medium | To Do | To Do | To Do | To Do |
| 166 | Fraction to Recurring Decimal | Medium | To Do | To Do | To Do | To Do |
| 167 | Two Sum II - Input array is sorted | Easy | JavaScript | To Do | To Do | To Do |
| 168 | Excel Sheet Column Title | Easy | To Do | Python | To Do | To Do |
| 169 | Majority Element | Easy | JavaScript | To Do | To Do | To Do |
| 170 | Two Sum III - Data structure design 🔒 | Easy | To Do | To Do | To Do | To Do |
| 171 | Excel Sheet Column Number | Easy | To Do | Python | To Do | To Do |
| 172 | Factorial Trailing Zeroes | Easy | To Do | Python | To Do | To Do |
| 173 | Binary Search Tree Iterator | Medium | To Do | To Do | To Do | To Do |
| 174 | Dungeon Game | Hard | To Do | To Do | To Do | To Do |
| 179 | Largest Number | Medium | To Do | To Do | To Do | To Do |
| 186 | Reverse Words in a String II 🔒 | Medium | To Do | To Do | To Do | To Do |
| 187 | Repeated DNA Sequences | Medium | To Do | To Do | To Do | To Do |
| 188 | Best Time to Buy and Sell Stock IV | Hard | To Do | To Do | To Do | To Do |
| 189 | Rotate Array | Easy | JavaScript | To Do | To Do | To Do |
| 190 | Reverse Bits | Easy | To Do | To Do | To Do | To Do |
| 191 | Number of 1 Bits | Easy | To Do | To Do | To Do | To Do |
| 198 | House Robber | Easy | To Do | To Do | To Do | To Do |
| 199 | Binary Tree Right Side View | Medium | To Do | To Do | To Do | To Do |
| 200 | Number of Islands | Medium | To Do | To Do | To Do | To Do |
| 201 | Bitwise AND of Numbers Range | Medium | To Do | To Do | To Do | To Do |
| 202 | Happy Number | Easy | To Do | To Do | To Do | To Do |
| 203 | Remove Linked List Elements | Easy | To Do | To Do | To Do | To Do |
| 204 | Count Primes | Easy | To Do | Python | To Do | To Do |
| 205 | Isomorphic Strings | Easy | To Do | Python | To Do | To Do |
| 206 | Reverse Linked List | Easy | To Do | Python | To Do | To Do |
| 207 | Course Schedule | Medium | To Do | To Do | To Do | To Do |
| 208 | Implement Trie (Prefix Tree) | Medium | To Do | To Do | To Do | To Do |
| 209 | Minimum Size Subarray Sum | Medium | To Do | To Do | To Do | To Do |
| 210 | Course Schedule II | Medium | To Do | To Do | To Do | To Do |
| 211 | Add and Search Word - Data structure design | Medium | To Do | To Do | To Do | To Do |
| 212 | Word Search II | Hard | To Do | To Do | To Do | To Do |
| 213 | House Robber II | Medium | To Do | To Do | To Do | To Do |
| 214 | Shortest Palindrome | Hard | To Do | To Do | To Do | To Do |
| 215 | Kth Largest Element in an Array | Medium | JavaScript | To Do | To Do | To Do |
| 216 | Combination Sum III | Medium | To Do | To Do | To Do | To Do |
| 217 | Contains Duplicate | Easy | JavaScript | To Do | To Do | To Do |
| 218 | The Skyline Problem | Hard | To Do | To Do | To Do | To Do |
| 219 | Contains Duplicate II | Easy | JavaScript | To Do | To Do | To Do |
| 220 | Contains Duplicate III | Medium | JavaScript | To Do | To Do | To Do |
| 221 | Maximal Square | Medium | To Do | Python | To Do | To Do |
| 222 | Count Complete Tree Nodes | Medium | To Do | To Do | To Do | To Do |
| 223 | Rectangle Area | Medium | To Do | To Do | To Do | To Do |
| 224 | Basic Calculator | Hard | To Do | To Do | To Do | To Do |
| 225 | Implement Stack using Queues | Easy | To Do | To Do | To Do | To Do |
| 226 | Invert Binary Tree | Easy | To Do | Python | To Do | To Do |
| 227 | Basic Calculator II | Medium | To Do | To Do | To Do | To Do |
| 228 | Summary Ranges | Medium | To Do | To Do | To Do | To Do |
| 229 | Majority Element II | Medium | To Do | To Do | To Do | To Do |
| 230 | Kth Smallest Element in a BST | Medium | To Do | To Do | To Do | To Do |
| 231 | Power of Two | Easy | To Do | To Do | To Do | To Do |
| 232 | Implement Queue using Stacks | Easy | To Do | To Do | To Do | To Do |
| 233 | Number of Digit One | Hard | To Do | To Do | To Do | To Do |
| 234 | Palindrome Linked List | Easy | To Do | Python | To Do | To Do |
| 235 | Lowest Common Ancestor of a Binary Search Tree | Easy | To Do | To Do | To Do | To Do |
| 236 | Lowest Common Ancestor of a Binary Tree | Medium | To Do | To Do | To Do | To Do |
| 237 | Delete Node in a Linked List | Easy | To Do | To Do | To Do | To Do |
| 238 | Product of Array Except Self | Medium | To Do | To Do | To Do | To Do |
| 239 | Sliding Window Maximum | Hard | To Do | To Do | To Do | To Do |
| 240 | Search a 2D Matrix II | Medium | To Do | To Do | To Do | To Do |
| 241 | Different Ways to Add Parentheses | Medium | To Do | To Do | To Do | To Do |
| 242 | Valid Anagram | Easy | To Do | To Do | To Do | To Do |
| 243 | Shortest Word Distance 🔒 | Easy | To Do | To Do | To Do | To Do |
| 244 | Shortest Word Distance II 🔒 | Medium | To Do | To Do | To Do | To Do |
| 245 | Shortest Word Distance III 🔒 | Medium | To Do | To Do | To Do | To Do |
| 246 | Strobogrammatic Number 🔒 | Easy | To Do | To Do | To Do | To Do |
| 247 | Strobogrammatic Number II 🔒 | Medium | To Do | To Do | To Do | To Do |
| 248 | Strobogrammatic Number III 🔒 | Hard | To Do | To Do | To Do | To Do |
| 249 | Group Shifted Strings 🔒 | Medium | To Do | To Do | To Do | To Do |
| 250 | Count Univalue Subtrees 🔒 | Medium | To Do | To Do | To Do | To Do |
| 251 | Flatten 2D Vector 🔒 | Medium | To Do | To Do | To Do | To Do |
| 252 | Meeting Rooms 🔒 | Easy | To Do | To Do | To Do | To Do |
| 253 | Meeting Rooms II 🔒 | Medium | To Do | To Do | To Do | To Do |
| 254 | Factor Combinations 🔒 | Medium | To Do | To Do | To Do | To Do |
| 255 | Verify Preorder Sequence in Binary Search Tree 🔒 | Medium | To Do | To Do | To Do | To Do |
| 256 | Paint House 🔒 | Easy | To Do | To Do | To Do | To Do |
| 257 | Binary Tree Paths | Easy | To Do | To Do | To Do | To Do |
| 258 | Add Digits | Easy | To Do | To Do | To Do | To Do |
| 259 | 3Sum Smaller 🔒 | Medium | To Do | To Do | To Do | To Do |
| 260 | Single Number III | Medium | To Do | To Do | To Do | To Do |
| 261 | Graph Valid Tree 🔒 | Medium | To Do | To Do | To Do | To Do |
| 263 | Ugly Number | Easy | To Do | To Do | To Do | To Do |
| 264 | Ugly Number II | Medium | To Do | To Do | To Do | To Do |
| 265 | Paint House II 🔒 | Hard | To Do | To Do | To Do | To Do |
| 266 | Palindrome Permutation 🔒 | Easy | To Do | To Do | To Do | To Do |
| 267 | Palindrome Permutation II 🔒 | Medium | To Do | To Do | To Do | To Do |
| 268 | Missing Number | Easy | JavaScript | To Do | To Do | To Do |
| 269 | Alien Dictionary 🔒 | Hard | To Do | To Do | To Do | To Do |
| 270 | Closest Binary Search Tree Value 🔒 | Easy | To Do | To Do | To Do | To Do |
| 271 | Encode and Decode Strings 🔒 | Medium | To Do | To Do | To Do | To Do |
| 272 | Closest Binary Search Tree Value II 🔒 | Hard | To Do | To Do | To Do | To Do |
| 273 | Integer to English Words | Hard | To Do | To Do | To Do | To Do |
| 274 | H-Index | Medium | To Do | To Do | To Do | To Do |
| 275 | H-Index II | Medium | To Do | To Do | To Do | To Do |
| 276 | Paint Fence 🔒 | Easy | To Do | To Do | To Do | To Do |
| 277 | Find the Celebrity 🔒 | Medium | To Do | To Do | To Do | To Do |
| 278 | First Bad Version | Easy | JavaScript | To Do | To Do | To Do |
| 279 | Perfect Squares | Medium | To Do | To Do | To Do | To Do |
| 280 | Wiggle Sort 🔒 | Medium | To Do | To Do | To Do | To Do |
| 281 | Zigzag Iterator 🔒 | Medium | To Do | To Do | To Do | To Do |
| 282 | Expression Add Operators | Hard | To Do | To Do | To Do | To Do |
| 283 | Move Zeroes | Easy | JavaScript | To Do | To Do | To Do |
| 284 | Peeking Iterator | Medium | To Do | To Do | To Do | To Do |
| 285 | Inorder Successor in BST 🔒 | Medium | To Do | To Do | To Do | To Do |
| 286 | Walls and Gates 🔒 | Medium | To Do | To Do | To Do | To Do |
| 287 | Find the Duplicate Number | Medium | JavaScript | To Do | To Do | To Do |
| 288 | Unique Word Abbreviation 🔒 | Medium | To Do | To Do | To Do | To Do |
| 289 | Game of Life | Medium | To Do | To Do | To Do | To Do |
| 290 | Word Pattern | Easy | To Do | To Do | To Do | To Do |
| 291 | Word Pattern II 🔒 | Hard | To Do | To Do | To Do | To Do |
| 292 | Nim Game | Easy | To Do | To Do | To Do | To Do |
| 293 | Flip Game 🔒 | Easy | To Do | To Do | To Do | To Do |
| 294 | Flip Game II 🔒 | Medium | To Do | To Do | To Do | To Do |
| 295 | Find Median from Data Stream | Hard | To Do | To Do | To Do | To Do |
| 296 | Best Meeting Point 🔒 | Hard | To Do | To Do | To Do | To Do |
| 297 | Serialize and Deserialize Binary Tree | Hard | To Do | To Do | To Do | To Do |
| 298 | Binary Tree Longest Consecutive Sequence 🔒 | Medium | To Do | To Do | To Do | To Do |
| 299 | Bulls and Cows | Medium | To Do | To Do | To Do | To Do |
| 300 | Longest Increasing Subsequence | Medium | To Do | To Do | To Do | To Do |
| 301 | Remove Invalid Parentheses | Hard | To Do | To Do | To Do | To Do |
| 302 | Smallest Rectangle Enclosing Black Pixels 🔒 | Hard | To Do | To Do | To Do | To Do |
| 303 | Range Sum Query - Immutable | Easy | To Do | To Do | To Do | To Do |
| 304 | Range Sum Query 2D - Immutable | Medium | To Do | To Do | To Do | To Do |
| 305 | Number of Islands II 🔒 | Hard | To Do | To Do | To Do | To Do |
| 306 | Additive Number | Medium | To Do | To Do | To Do | To Do |
| 307 | Range Sum Query - Mutable | Medium | To Do | To Do | To Do | To Do |
| 308 | Range Sum Query 2D - Mutable 🔒 | Hard | To Do | To Do | To Do | To Do |
| 309 | Best Time to Buy and Sell Stock with Cooldown | Medium | To Do | To Do | To Do | To Do |
| 310 | Minimum Height Trees | Medium | To Do | To Do | To Do | To Do |
| 311 | Sparse Matrix Multiplication 🔒 | Medium | To Do | To Do | To Do | To Do |
| 312 | Burst Balloons | Hard | To Do | To Do | To Do | To Do |
| 313 | Super Ugly Number | Medium | To Do | To Do | To Do | To Do |
| 314 | Binary Tree Vertical Order Traversal 🔒 | Medium | To Do | To Do | To Do | To Do |
| 315 | Count of Smaller Numbers After Self | Hard | To Do | To Do | To Do | To Do |
| 316 | Remove Duplicate Letters | Hard | To Do | To Do | To Do | To Do |
| 317 | Shortest Distance from All Buildings 🔒 | Hard | To Do | To Do | To Do | To Do |
| 318 | Maximum Product of Word Lengths | Medium | To Do | To Do | To Do | To Do |
| 319 | Bulb Switcher | Medium | To Do | To Do | To Do | To Do |
| 320 | Generalized Abbreviation 🔒 | Medium | To Do | To Do | To Do | To Do |
| 321 | Create Maximum Number | Hard | To Do | To Do | To Do | To Do |
| 322 | Coin Change | Medium | To Do | To Do | To Do | To Do |
| 323 | Number of Connected Components in an Undirected Graph 🔒 | Medium | To Do | To Do | To Do | To Do |
| 324 | Wiggle Sort II | Medium | To Do | To Do | To Do | To Do |
| 325 | Maximum Size Subarray Sum Equals k 🔒 | Medium | To Do | To Do | To Do | To Do |
| 326 | Power of Three | Easy | To Do | To Do | To Do | To Do |
| 327 | Count of Range Sum | Hard | To Do | To Do | To Do | To Do |
| 328 | Odd Even Linked List | Medium | To Do | To Do | To Do | To Do |
| 329 | Longest Increasing Path in a Matrix | Hard | To Do | To Do | To Do | To Do |
| 330 | Patching Array | Hard | To Do | To Do | To Do | To Do |
| 331 | Verify Preorder Serialization of a Binary Tree | Medium | To Do | To Do | To Do | To Do |
| 332 | Reconstruct Itinerary | Medium | To Do | To Do | To Do | To Do |
| 333 | Largest BST Subtree 🔒 | Medium | To Do | To Do | To Do | To Do |
| 334 | Increasing Triplet Subsequence | Medium | To Do | To Do | To Do | To Do |
| 335 | Self Crossing | Hard | To Do | To Do | To Do | To Do |
| 336 | Palindrome Pairs | Hard | To Do | To Do | To Do | To Do |
| 337 | House Robber III | Medium | To Do | To Do | To Do | To Do |
| 338 | Counting Bits | Medium | To Do | To Do | To Do | To Do |
| 339 | Nested List Weight Sum 🔒 | Easy | To Do | To Do | To Do | To Do |
| 340 | Longest Substring with At Most K Distinct Characters 🔒 | Hard | To Do | To Do | To Do | To Do |
| 341 | Flatten Nested List Iterator | Medium | To Do | To Do | To Do | To Do |
| 342 | Power of Four | Easy | To Do | To Do | To Do | To Do |
| 343 | Integer Break | Medium | To Do | To Do | To Do | To Do |
| 344 | Reverse String | Easy | To Do | To Do | To Do | To Do |
| 345 | Reverse Vowels of a String | Easy | To Do | To Do | To Do | To Do |
| 346 | Moving Average from Data Stream 🔒 | Easy | To Do | To Do | To Do | To Do |
| 347 | Top K Frequent Elements | Medium | To Do | To Do | To Do | To Do |
| 348 | Design Tic-Tac-Toe 🔒 | Medium | To Do | To Do | To Do | To Do |
| 349 | Intersection of Two Arrays | Easy | JavaScript | To Do | To Do | To Do |
| 350 | Intersection of Two Arrays II | Easy | JavaScript | To Do | To Do | To Do |
| 351 | Android Unlock Patterns 🔒 | Medium | To Do | To Do | To Do | To Do |
| 352 | Data Stream as Disjoint Intervals | Hard | To Do | To Do | To Do | To Do |
| 353 | Design Snake Game 🔒 | Medium | To Do | To Do | To Do | To Do |
| 354 | Russian Doll Envelopes | Hard | To Do | To Do | To Do | To Do |
| 355 | Design Twitter | Medium | To Do | To Do | To Do | To Do |
| 356 | Line Reflection 🔒 | Medium | To Do | To Do | To Do | To Do |
| 357 | Count Numbers with Unique Digits | Medium | To Do | To Do | To Do | To Do |
| 358 | Rearrange String k Distance Apart 🔒 | Hard | To Do | To Do | To Do | To Do |
| 359 | Logger Rate Limiter 🔒 | Easy | To Do | To Do | To Do | To Do |
| 360 | Sort Transformed Array 🔒 | Medium | To Do | To Do | To Do | To Do |
| 361 | Bomb Enemy 🔒 | Medium | To Do | To Do | To Do | To Do |
| 362 | Design Hit Counter 🔒 | Medium | To Do | To Do | To Do | To Do |
| 363 | Max Sum of Rectangle No Larger Than K | Hard | To Do | To Do | To Do | To Do |
| 364 | Nested List Weight Sum II 🔒 | Medium | To Do | To Do | To Do | To Do |
| 365 | Water and Jug Problem | Medium | To Do | To Do | To Do | To Do |
| 366 | Find Leaves of Binary Tree 🔒 | Medium | To Do | To Do | To Do | To Do |
| 367 | Valid Perfect Square | Easy | JavaScript | To Do | To Do | To Do |
| 368 | Largest Divisible Subset | Medium | To Do | To Do | To Do | To Do |
| 369 | Plus One Linked List 🔒 | Medium | To Do | To Do | To Do | To Do |
| 370 | Range Addition 🔒 | Medium | To Do | To Do | To Do | To Do |
| 371 | Sum of Two Integers | Easy | To Do | To Do | To Do | To Do |
| 372 | Super Pow | Medium | To Do | To Do | To Do | To Do |
| 373 | Find K Pairs with Smallest Sums | Medium | To Do | To Do | To Do | To Do |
| 374 | Guess Number Higher or Lower | Easy | To Do | Python | To Do | To Do |
| 375 | Guess Number Higher or Lower II | Medium | To Do | To Do | To Do | To Do |
| 376 | Wiggle Subsequence | Medium | To Do | To Do | To Do | To Do |
| 377 | Combination Sum IV | Medium | To Do | To Do | To Do | To Do |
| 378 | Kth Smallest Element in a Sorted Matrix | Medium | To Do | To Do | To Do | To Do |
| 379 | Design Phone Directory 🔒 | Medium | To Do | To Do | To Do | To Do |
| 380 | Insert Delete GetRandom O(1) | Medium | To Do | To Do | To Do | To Do |
| 381 | Insert Delete GetRandom O(1) - Duplicates allowed | Hard | To Do | To Do | To Do | To Do |
| 382 | Linked List Random Node | Medium | To Do | To Do | To Do | To Do |
| 383 | Ransom Note | Easy | To Do | To Do | To Do | To Do |
| 384 | Shuffle an Array | Medium | To Do | To Do | To Do | To Do |
| 385 | Mini Parser | Medium | To Do | To Do | To Do | To Do |
| 386 | Lexicographical Numbers | Medium | To Do | To Do | To Do | To Do |
| 387 | First Unique Character in a String | Easy | To Do | To Do | To Do | To Do |
| 388 | Longest Absolute File Path | Medium | To Do | To Do | To Do | To Do |
| 389 | Find the Difference | Easy | To Do | To Do | To Do | To Do |
| 390 | Elimination Game | Medium | To Do | To Do | To Do | To Do |
| 391 | Perfect Rectangle | Hard | To Do | To Do | To Do | To Do |
| 392 | Is Subsequence | Medium | To Do | To Do | To Do | To Do |
| 393 | UTF-8 Validation | Medium | To Do | To Do | To Do | To Do |
| 394 | Decode String | Medium | To Do | To Do | To Do | To Do |
| 395 | Longest Substring with At Least K Repeating Characters | Medium | To Do | To Do | To Do | To Do |
| 396 | Rotate Function | Medium | To Do | To Do | To Do | To Do |
| 397 | Integer Replacement | Medium | To Do | To Do | To Do | To Do |
| 398 | Random Pick Index | Medium | To Do | To Do | To Do | To Do |
| 399 | Evaluate Division | Medium | To Do | To Do | To Do | To Do |
| 400 | Nth Digit | Easy | To Do | To Do | To Do | To Do |
| 401 | Binary Watch | Easy | To Do | To Do | To Do | To Do |
| 402 | Remove K Digits | Medium | To Do | To Do | To Do | To Do |
| 403 | Frog Jump | Hard | To Do | To Do | To Do | To Do |
| 404 | Sum of Left Leaves | Easy | To Do | To Do | To Do | To Do |
| 405 | Convert a Number to Hexadecimal | Easy | To Do | To Do | To Do | To Do |
| 406 | Queue Reconstruction by Height | Medium | To Do | To Do | To Do | To Do |
| 407 | Trapping Rain Water II | Hard | To Do | To Do | To Do | To Do |
| 408 | Valid Word Abbreviation 🔒 | Easy | To Do | To Do | To Do | To Do |
| 409 | Longest Palindrome | Easy | To Do | To Do | To Do | To Do |
| 410 | Split Array Largest Sum | Hard | To Do | To Do | To Do | To Do |
| 411 | Minimum Unique Word Abbreviation 🔒 | Hard | To Do | To Do | To Do | To Do |
| 412 | Fizz Buzz | Easy | To Do | To Do | To Do | To Do |
| 413 | Arithmetic Slices | Medium | To Do | To Do | To Do | To Do |
| 414 | Third Maximum Number | Easy | JavaScript | To Do | To Do | To Do |
| 415 | Add Strings | Easy | To Do | Python | To Do | To Do |
| 416 | Partition Equal Subset Sum | Medium | To Do | To Do | To Do | To Do |
| 417 | Pacific Atlantic Water Flow | Medium | To Do | To Do | To Do | To Do |
| 418 | Sentence Screen Fitting 🔒 | Medium | To Do | To Do | To Do | To Do |
| 419 | Battleships in a Board | Medium | To Do | To Do | To Do | To Do |
| 420 | Strong Password Checker | Hard | To Do | To Do | To Do | To Do |
| 421 | Maximum XOR of Two Numbers in an Array | Medium | To Do | To Do | To Do | To Do |
| 422 | Valid Word Square 🔒 | Easy | To Do | To Do | To Do | To Do |
| 423 | Reconstruct Original Digits from English | Medium | To Do | To Do | To Do | To Do |
| 424 | Longest Repeating Character Replacement | Medium | To Do | To Do | To Do | To Do |
| 425 | Word Squares 🔒 | Hard | To Do | To Do | To Do | To Do |
| 432 | All O`one Data Structure | Hard | To Do | To Do | To Do | To Do |
| 434 | Number of Segments in a String | Easy | To Do | To Do | To Do | To Do |
| 435 | Non-overlapping Intervals | Medium | To Do | To Do | To Do | To Do |
| 436 | Find Right Interval | Medium | To Do | To Do | To Do | To Do |
| 437 | Path Sum III | Easy | To Do | To Do | To Do | To Do |
| 438 | Find All Anagrams in a String | Easy | To Do | To Do | To Do | To Do |
| 439 | Ternary Expression Parser 🔒 | Medium | To Do | To Do | To Do | To Do |
| 440 | K-th Smallest in Lexicographical Order | Hard | To Do | To Do | To Do | To Do |
| 441 | Arranging Coins | Easy | To Do | To Do | To Do | To Do |
| 442 | Find All Duplicates in an Array | Medium | JavaScript | To Do | To Do | To Do |
| 443 | String Compression | Easy | To Do | To Do | To Do | To Do |
| 444 | Sequence Reconstruction 🔒 | Medium | To Do | To Do | To Do | To Do |
| 445 | Add Two Numbers II | Medium | To Do | To Do | To Do | To Do |
| 446 | Arithmetic Slices II - Subsequence | Hard | To Do | To Do | To Do | To Do |
| 447 | Number of Boomerangs | Easy | To Do | To Do | To Do | To Do |
| 448 | Find All Numbers Disappeared in an Array | Easy | JavaScript | To Do | To Do | To Do |
| 449 | Serialize and Deserialize BST | Medium | To Do | To Do | To Do | To Do |
| 450 | Delete Node in a BST | Medium | To Do | To Do | To Do | To Do |
| 451 | Sort Characters By Frequency | Medium | To Do | To Do | To Do | To Do |
| 452 | Minimum Number of Arrows to Burst Balloons | Medium | To Do | To Do | To Do | To Do |
| 453 | Minimum Moves to Equal Array Elements | Easy | To Do | Python | To Do | To Do |
| 454 | 4Sum II | Medium | To Do | To Do | To Do | To Do |
| 455 | Assign Cookies | Easy | To Do | To Do | To Do | To Do |
| 456 | 132 Pattern | Medium | To Do | To Do | To Do | To Do |
| 459 | Repeated Substring Pattern | Easy | To Do | To Do | To Do | To Do |
| 460 | LFU Cache | Hard | To Do | To Do | To Do | To Do |
| 461 | Hamming Distance | Easy | To Do | To Do | To Do | To Do |
| 462 | Minimum Moves to Equal Array Elements II | Medium | To Do | Python | To Do | To Do |
| 463 | Island Perimeter | Easy | To Do | To Do | To Do | To Do |
| 464 | Can I Win | Medium | To Do | To Do | To Do | To Do |
| 465 | Optimal Account Balancing 🔒 | Hard | To Do | To Do | To Do | To Do |
| 466 | Count The Repetitions | Hard | To Do | To Do | To Do | To Do |
| 467 | Unique Substrings in Wraparound String | Medium | To Do | To Do | To Do | To Do |
| 468 | Validate IP Address | Medium | To Do | To Do | To Do | To Do |
| 469 | Convex Polygon 🔒 | Medium | To Do | To Do | To Do | To Do |
| 471 | Encode String with Shortest Length 🔒 | Hard | To Do | To Do | To Do | To Do |
| 472 | Concatenated Words | Hard | To Do | To Do | To Do | To Do |
| 473 | Matchsticks to Square | Medium | To Do | To Do | To Do | To Do |
| 474 | Ones and Zeroes | Medium | To Do | To Do | To Do | To Do |
| 475 | Heaters | Easy | To Do | To Do | To Do | To Do |
| 476 | Number Complement | Easy | To Do | To Do | To Do | To Do |
| 477 | Total Hamming Distance | Medium | To Do | To Do | To Do | To Do |
| 479 | Largest Palindrome Product | Easy | To Do | To Do | To Do | To Do |
| 480 | Sliding Window Median | Hard | To Do | To Do | To Do | To Do |
| 481 | Magical String | Medium | To Do | To Do | To Do | To Do |
| 482 | License Key Formatting | Easy | To Do | To Do | To Do | To Do |
| 483 | Smallest Good Base | Hard | To Do | To Do | To Do | To Do |
| 484 | Find Permutation 🔒 | Medium | To Do | To Do | To Do | To Do |
| 485 | Max Consecutive Ones | Easy | JavaScript | To Do | To Do | To Do |
| 486 | Predict the Winner | Medium | To Do | To Do | To Do | To Do |
| 487 | Max Consecutive Ones II 🔒 | Medium | To Do | To Do | To Do | To Do |
| 488 | Zuma Game | Hard | To Do | To Do | To Do | To Do |
| 490 | The Maze 🔒 | Medium | To Do | To Do | To Do | To Do |
| 491 | Increasing Subsequences | Medium | To Do | To Do | To Do | To Do |
| 492 | Construct the Rectangle | Easy | To Do | To Do | To Do | To Do |
| 493 | Reverse Pairs | Hard | To Do | To Do | To Do | To Do |
| 494 | Target Sum | Medium | To Do | To Do | To Do | To Do |
| 495 | Teemo Attacking | Medium | To Do | To Do | To Do | To Do |
| 496 | Next Greater Element I | Easy | To Do | To Do | To Do | To Do |
| 498 | Diagonal Traverse | Medium | To Do | To Do | To Do | To Do |
| 499 | The Maze III 🔒 | Hard | To Do | To Do | To Do | To Do |
| 500 | Keyboard Row | Easy | To Do | To Do | To Do | To Do |
| 501 | Find Mode in Binary Search Tree | Easy | To Do | To Do | To Do | To Do |
| 502 | IPO | Hard | To Do | To Do | To Do | To Do |
| 503 | Next Greater Element II | Medium | To Do | To Do | To Do | To Do |
| 504 | Base 7 | Easy | To Do | To Do | To Do | To Do |
| 505 | The Maze II 🔒 | Medium | To Do | To Do | To Do | To Do |
| 506 | Relative Ranks | Easy | To Do | To Do | To Do | To Do |
| 507 | Perfect Number | Easy | To Do | To Do | To Do | To Do |
| 508 | Most Frequent Subtree Sum | Medium | To Do | To Do | To Do | To Do |
| 513 | Find Bottom Left Tree Value | Medium | To Do | To Do | To Do | To Do |
| 514 | Freedom Trail | Hard | To Do | To Do | To Do | To Do |
| 515 | Find Largest Value in Each Tree Row | Medium | To Do | To Do | To Do | To Do |
| 516 | Longest Palindromic Subsequence | Medium | To Do | To Do | To Do | To Do |
| 517 | Super Washing Machines | Hard | To Do | To Do | To Do | To Do |
| 520 | Detect Capital | Easy | To Do | To Do | To Do | To Do |
| 521 | Longest Uncommon Subsequence I | Easy | To Do | To Do | To Do | To Do |
| 522 | Longest Uncommon Subsequence II | Medium | To Do | To Do | To Do | To Do |
| 523 | Continuous Subarray Sum | Medium | To Do | To Do | To Do | To Do |
| 524 | Longest Word in Dictionary through Deleting | Medium | To Do | To Do | To Do | To Do |
| 525 | Contiguous Array | Medium | To Do | To Do | To Do | To Do |
| 526 | Beautiful Arrangement | Medium | To Do | To Do | To Do | To Do |
| 527 | Word Abbreviation 🔒 | Hard | To Do | To Do | To Do | To Do |
| 529 | Minesweeper | Medium | To Do | To Do | To Do | To Do |
| 530 | Minimum Absolute Difference in BST | Easy | To Do | To Do | To Do | To Do |
| 531 | Lonely Pixel I 🔒 | Medium | To Do | To Do | To Do | To Do |
| 532 | K-diff Pairs in an Array | Easy | To Do | To Do | To Do | To Do |
| 533 | Lonely Pixel II 🔒 | Medium | To Do | To Do | To Do | To Do |
| 535 | Encode and Decode TinyURL | Medium | To Do | To Do | To Do | To Do |
| 536 | Construct Binary Tree from String 🔒 | Medium | To Do | To Do | To Do | To Do |
| 537 | Complex Number Multiplication | Medium | To Do | To Do | To Do | To Do |
| 538 | Convert BST to Greater Tree | Easy | To Do | To Do | To Do | To Do |
| 539 | Minimum Time Difference | Medium | To Do | To Do | To Do | To Do |
| 540 | Single Element in a Sorted Array | Medium | To Do | To Do | To Do | To Do |
| 541 | Reverse String II | Easy | To Do | To Do | To Do | To Do |
| 542 | 01 Matrix | Medium | To Do | To Do | To Do | To Do |
| 543 | Diameter of Binary Tree | Easy | To Do | To Do | To Do | To Do |
| 544 | Output Contest Matches 🔒 | Medium | To Do | To Do | To Do | To Do |
| 545 | Boundary of Binary Tree 🔒 | Medium | To Do | To Do | To Do | To Do |
| 546 | Remove Boxes | Hard | To Do | To Do | To Do | To Do |
| 547 | Friend Circles | Medium | To Do | To Do | To Do | To Do |
| 548 | Split Array with Equal Sum 🔒 | Medium | To Do | To Do | To Do | To Do |
| 549 | Binary Tree Longest Consecutive Sequence II 🔒 | Medium | To Do | To Do | To Do | To Do |
| 551 | Student Attendance Record I | Easy | To Do | To Do | To Do | To Do |
| 552 | Student Attendance Record II | Hard | To Do | To Do | To Do | To Do |
| 553 | Optimal Division | Medium | To Do | To Do | To Do | To Do |
| 554 | Brick Wall | Medium | To Do | To Do | To Do | To Do |
| 555 | Split Concatenated Strings 🔒 | Medium | To Do | To Do | To Do | To Do |
| 556 | Next Greater Element III | Medium | To Do | To Do | To Do | To Do |
| 557 | Reverse Words in a String III | Easy | To Do | To Do | To Do | To Do |
| 560 | Subarray Sum Equals K | Medium | To Do | To Do | To Do | To Do |
| 561 | Array Partition I | Easy | To Do | To Do | To Do | To Do |
| 562 | Longest Line of Consecutive One in Matrix 🔒 | Medium | To Do | To Do | To Do | To Do |
| 563 | Binary Tree Tilt | Easy | To Do | To Do | To Do | To Do |
| 564 | Find the Closest Palindrome | Hard | To Do | To Do | To Do | To Do |
| 565 | Array Nesting | Medium | To Do | To Do | To Do | To Do |
| 566 | Reshape the Matrix | Easy | To Do | To Do | To Do | To Do |
| 567 | Permutation in String | Medium | To Do | To Do | To Do | To Do |
| 568 | Maximum Vacation Days 🔒 | Hard | To Do | To Do | To Do | To Do |
| 572 | Subtree of Another Tree | Easy | To Do | To Do | To Do | To Do |
| 573 | Squirrel Simulation 🔒 | Medium | To Do | To Do | To Do | To Do |
| 575 | Distribute Candies | Easy | To Do | To Do | To Do | To Do |
| 576 | Out of Boundary Paths | Medium | To Do | To Do | To Do | To Do |
| 581 | Shortest Unsorted Continuous Subarray | Easy | To Do | To Do | To Do | To Do |
| 582 | Kill Process 🔒 | Medium | To Do | To Do | To Do | To Do |
| 583 | Delete Operation for Two Strings | Medium | To Do | To Do | To Do | To Do |
| 587 | Erect the Fence | Hard | To Do | To Do | To Do | To Do |
| 588 | Design In-Memory File System 🔒 | Hard | To Do | To Do | To Do | To Do |
| 591 | Tag Validator | Hard | To Do | To Do | To Do | To Do |
| 592 | Fraction Addition and Subtraction | Medium | To Do | To Do | To Do | To Do |
| 593 | Valid Square | Medium | To Do | To Do | To Do | To Do |
| 594 | Longest Harmonious Subsequence | Easy | To Do | To Do | To Do | To Do |
| 598 | Range Addition II | Easy | To Do | To Do | To Do | To Do |
| 599 | Minimum Index Sum of Two Lists | Easy | To Do | To Do | To Do | To Do |
| 600 | Non-negative Integers without Consecutive Ones | Hard | To Do | To Do | To Do | To Do |
| 604 | Design Compressed String Iterator 🔒 | Easy | To Do | To Do | To Do | To Do |
| 605 | Can Place Flowers | Easy | To Do | To Do | To Do | To Do |
| 606 | Construct String from Binary Tree | Easy | To Do | To Do | To Do | To Do |
| 609 | Find Duplicate File in System | Medium | To Do | Python | To Do | To Do |
| 611 | Valid Triangle Number | Medium | To Do | To Do | To Do | To Do |
| 616 | Add Bold Tag in String 🔒 | Medium | To Do | To Do | To Do | To Do |
| 617 | Merge Two Binary Trees | Easy | To Do | To Do | To Do | To Do |
| 621 | Task Scheduler | Medium | To Do | To Do | To Do | To Do |
| 623 | Add One Row to Tree | Medium | To Do | To Do | To Do | To Do |
| 624 | Maximum Distance in Arrays 🔒 | Easy | To Do | To Do | To Do | To Do |
| 625 | Minimum Factorization 🔒 | Medium | To Do | To Do | To Do | To Do |
| 628 | Maximum Product of Three Numbers | Easy | To Do | To Do | To Do | To Do |
| 629 | K Inverse Pairs Array | Hard | To Do | To Do | To Do | To Do |
| 630 | Course Schedule III | Hard | To Do | To Do | To Do | To Do |
| 631 | Design Excel Sum Formula 🔒 | Hard | To Do | To Do | To Do | To Do |
| 632 | Smallest Range | Hard | To Do | To Do | To Do | To Do |
| 633 | Sum of Square Numbers | Easy | To Do | To Do | To Do | To Do |
| 634 | Find the Derangement of An Array 🔒 | Medium | To Do | To Do | To Do | To Do |
| 635 | Design Log Storage System 🔒 | Medium | To Do | To Do | To Do | To Do |
| 636 | Exclusive Time of Functions | Medium | To Do | To Do | To Do | To Do |
| 637 | Average of Levels in Binary Tree | Easy | To Do | Python | To Do | To Do |
| 638 | Shopping Offers | Medium | To Do | To Do | To Do | To Do |
| 639 | Decode Ways II | Hard | To Do | To Do | To Do | To Do |
| 640 | Solve the Equation | Medium | To Do | To Do | To Do | To Do |
| 642 | Design Search Autocomplete System 🔒 | Hard | To Do | To Do | To Do | To Do |
| 643 | Maximum Average Subarray I | Easy | To Do | To Do | To Do | To Do |
| 644 | Maximum Average Subarray II 🔒 | Hard | To Do | To Do | To Do | To Do |
| 645 | Set Mismatch | Easy | To Do | To Do | To Do | To Do |
| 646 | Maximum Length of Pair Chain | Medium | To Do | To Do | To Do | To Do |
| 647 | Palindromic Substrings | Medium | To Do | To Do | To Do | To Do |
| 648 | Replace Words | Medium | To Do | To Do | To Do | To Do |
| 649 | Dota2 Senate | Medium | To Do | To Do | To Do | To Do |
| 650 | 2 Keys Keyboard | Medium | To Do | To Do | To Do | To Do |
| 651 | 4 Keys Keyboard 🔒 | Medium | To Do | To Do | To Do | To Do |
| 652 | Find Duplicate Subtrees | Medium | To Do | To Do | To Do | To Do |
| 653 | Two Sum IV - Input is a BST | Easy | To Do | To Do | To Do | To Do |
| 654 | Maximum Binary Tree | Medium | To Do | To Do | To Do | To Do |
| 655 | Print Binary Tree | Medium | To Do | To Do | To Do | To Do |
| 656 | Coin Path 🔒 | Hard | To Do | To Do | To Do | To Do |
| 657 | Judge Route Circle | Easy | To Do | To Do | To Do | To Do |
| 658 | Find K Closest Elements | Medium | To Do | To Do | To Do | To Do |
| 659 | Split Array into Consecutive Subsequences | Medium | To Do | To Do | To Do | To Do |
| 660 | Remove 9 🔒 | Hard | To Do | To Do | To Do | To Do |
| 661 | Image Smoother | Easy | To Do | To Do | To Do | To Do |
| 662 | Maximum Width of Binary Tree | Medium | To Do | To Do | To Do | To Do |
| 663 | Equal Tree Partition 🔒 | Medium | To Do | To Do | To Do | To Do |
| 664 | Strange Printer | Hard | To Do | To Do | To Do | To Do |
| 665 | Non-decreasing Array | Easy | To Do | To Do | To Do | To Do |
| 666 | Path Sum IV 🔒 | Medium | To Do | To Do | To Do | To Do |
| 667 | Beautiful Arrangement II | Medium | To Do | To Do | To Do | To Do |
| 668 | Kth Smallest Number in Multiplication Table | Hard | To Do | To Do | To Do | To Do |
| 669 | Trim a Binary Search Tree | Easy | To Do | To Do | To Do | To Do |
| 670 | Maximum Swap | Medium | To Do | To Do | To Do | To Do |
| 671 | Second Minimum Node In a Binary Tree | Easy | To Do | To Do | To Do | To Do |
| 672 | Bulb Switcher II | Medium | To Do | To Do | To Do | To Do |
| 673 | Number of Longest Increasing Subsequence | Medium | To Do | To Do | To Do | To Do |
| 674 | Longest Continuous Increasing Subsequence | Easy | To Do | To Do | To Do | To Do |
| 675 | Cut Off Trees for Golf Event | Hard | To Do | To Do | To Do | To Do |
| 676 | Implement Magic Dictionary | Medium | To Do | To Do | To Do | To Do |
| 677 | Map Sum Pairs | Medium | To Do | To Do | To Do | To Do |
| 678 | Valid Parenthesis String | Medium | To Do | To Do | To Do | To Do |
| 679 | 24 Game | Hard | To Do | To Do | To Do | To Do |
| 680 | Valid Palindrome II | Easy | To Do | To Do | To Do | To Do |
| 681 | Next Closest Time 🔒 | Medium | To Do | To Do | To Do | To Do |
| 682 | Baseball Game | Easy | To Do | To Do | To Do | To Do |
| 683 | K Empty Slots 🔒 | Hard | To Do | To Do | To Do | To Do |
| 684 | Redundant Connection | Medium | To Do | To Do | To Do | To Do |
| 685 | Redundant Connection II | Hard | To Do | To Do | To Do | To Do |
| 686 | Repeated String Match | Easy | To Do | To Do | To Do | To Do |
| 687 | Longest Univalue Path | Easy | To Do | To Do | To Do | To Do |
| 688 | Knight Probability in Chessboard | Medium | To Do | To Do | To Do | To Do |
| 689 | Maximum Sum of 3 Non-Overlapping Subarrays | Hard | To Do | To Do | To Do | To Do |
| 690 | Employee Importance | Easy | To Do | To Do | To Do | To Do |
| 691 | Stickers to Spell Word | Hard | To Do | To Do | To Do | To Do |
| 692 | Top K Frequent Words | Medium | To Do | To Do | To Do | To Do |
| 693 | Binary Number with Alternating Bits | Easy | To Do | To Do | To Do | To Do |
| 694 | Number of Distinct Islands 🔒 | Medium | To Do | To Do | To Do | To Do |
| 695 | Max Area of Island | Easy | To Do | To Do | To Do | To Do |
| 696 | Count Binary Substrings | Easy | To Do | To Do | To Do | To Do |
| 697 | Degree of an Array | Easy | To Do | To Do | To Do | To Do |
| 698 | Partition to K Equal Sum Subsets | Medium | To Do | To Do | To Do | To Do |
| 699 | Falling Squares | Hard | To Do | To Do | To Do | To Do |
| 711 | Number of Distinct Islands II 🔒 | Hard | To Do | To Do | To Do | To Do |
| 712 | Minimum ASCII Delete Sum for Two Strings | Medium | To Do | To Do | To Do | To Do |
| 713 | Subarray Product Less Than K | Medium | To Do | To Do | To Do | To Do |
| 714 | Best Time to Buy and Sell Stock with Transaction Fee | Medium | To Do | To Do | To Do | To Do |
| 715 | Range Module | Hard | To Do | To Do | To Do | To Do |
| 716 | Max Stack 🔒 | Hard | To Do | To Do | To Do | To Do |
| 717 | 1-bit and 2-bit Characters | Easy | To Do | To Do | To Do | To Do |
| 718 | Maximum Length of Repeated Subarray | Medium | To Do | To Do | To Do | To Do |
| 719 | Find K-th Smallest Pair Distance | Hard | To Do | To Do | To Do | To Do |
| 720 | Longest Word in Dictionary | Easy | To Do | To Do | To Do | To Do |
| 721 | Accounts Merge | Medium | To Do | To Do | To Do | To Do |
| 722 | Remove Comments | Medium | To Do | To Do | To Do | To Do |
| 723 | Candy Crush 🔒 | Medium | To Do | To Do | To Do | To Do |
| 724 | Find Pivot Index | Easy | To Do | To Do | To Do | To Do |
| 725 | Split Linked List in Parts | Medium | To Do | Python | To Do | To Do |
| 726 | Number of Atoms | Hard | To Do | To Do | To Do | To Do |
| 727 | Minimum Window Subsequence 🔒 | Hard | To Do | To Do | To Do | To Do |
| 728 | Self Dividing Numbers | Easy | To Do | To Do | To Do | To Do |
| 729 | My Calendar I | Medium | To Do | To Do | To Do | To Do |
| 730 | Count Different Palindromic Subsequences | Hard | To Do | To Do | To Do | To Do |
| 731 | My Calendar II | Medium | To Do | To Do | To Do | To Do |
| 732 | My Calendar III | Hard | To Do | To Do | To Do | To Do |
| 733 | Flood Fill | Easy | To Do | To Do | To Do | To Do |
| 734 | Sentence Similarity 🔒 | Easy | To Do | To Do | To Do | To Do |
| 735 | Asteroid Collision | Medium | To Do | To Do | To Do | To Do |
| 736 | Parse Lisp Expression | Hard | To Do | To Do | To Do | To Do |
| 737 | Sentence Similarity II 🔒 | Medium | To Do | To Do | To Do | To Do |
| 738 | Monotone Increasing Digits | Medium | To Do | To Do | To Do | To Do |
| 739 | Daily Temperatures | Medium | To Do | To Do | To Do | To Do |
| 740 | Delete and Earn | Medium | To Do | To Do | To Do | To Do |
| 741 | Cherry Pickup | Hard | To Do | To Do | To Do | To Do |
| 742 | Closest Leaf in a Binary Tree 🔒 | Medium | To Do | To Do | To Do | To Do |
| 743 | Network Delay Time | Medium | To Do | To Do | To Do | To Do |
| 744 | Find Smallest Letter Greater Than Target | Easy | To Do | To Do | To Do | To Do |
| 745 | Prefix and Suffix Search | Hard | To Do | To Do | To Do | To Do |
| 746 | Min Cost Climbing Stairs | Easy | To Do | To Do | To Do | To Do |
| 747 | Largest Number At Least Twice of Others | Easy | To Do | To Do | To Do | To Do |
| 748 | Shortest Completing Word | Medium | To Do | To Do | To Do | To Do |
| 749 | Contain Virus | Hard | To Do | To Do | To Do | To Do |
| 750 | Number Of Corner Rectangles 🔒 | Medium | To Do | To Do | To Do | To Do |
| 751 | IP to CIDR 🔒 | Easy | To Do | To Do | To Do | To Do |
| 752 | Open the Lock | Medium | To Do | To Do | To Do | To Do |
| 753 | Cracking the Safe | Hard | To Do | To Do | To Do | To Do |
| 754 | Reach a Number | Medium | To Do | To Do | To Do | To Do |
| 755 | Pour Water 🔒 | Medium | To Do | To Do | To Do | To Do |
| 756 | Pyramid Transition Matrix | Medium | To Do | To Do | To Do | To Do |
| 757 | Set Intersection Size At Least Two | Hard | To Do | To Do | To Do | To Do |
| 758 | Bold Words in String 🔒 | Easy | To Do | To Do | To Do | To Do |
| 759 | Employee Free Time 🔒 | Hard | To Do | To Do | To Do | To Do |
| 760 | Find Anagram Mappings 🔒 | Easy | To Do | To Do | To Do | To Do |
| 761 | Special Binary String | Hard | To Do | To Do | To Do | To Do |
| 762 | Prime Number of Set Bits in Binary Representation | Easy | To Do | To Do | To Do | To Do |
| 763 | Partition Labels | Medium | To Do | To Do | To Do | To Do |
| 764 | Largest Plus Sign | Medium | To Do | To Do | To Do | To Do |
| 765 | Couples Holding Hands | Hard | To Do | To Do | To Do | To Do |
| 766 | Toeplitz Matrix | Easy | To Do | To Do | To Do | To Do |
| 767 | Reorganize String | Medium | To Do | To Do | To Do | To Do |
| 768 | Max Chunks To Make Sorted II | Hard | To Do | To Do | To Do | To Do |
| 769 | Max Chunks To Make Sorted | Medium | To Do | To Do | To Do | To Do |
| 770 | Basic Calculator IV | Hard | To Do | To Do | To Do | To Do |
| 771 | Jewels and Stones | Easy | To Do | To Do | To Do | To Do |
| 772 | Basic Calculator III 🔒 | Hard | To Do | To Do | To Do | To Do |
| 773 | Sliding Puzzle | Hard | To Do | To Do | To Do | To Do |
| 774 | Minimize Max Distance to Gas Station 🔒 | Hard | To Do | To Do | To Do | To Do |
| 775 | Global and Local Inversions | Medium | To Do | To Do | To Do | To Do |
| 776 | Split BST 🔒 | Medium | To Do | To Do | To Do | To Do |
| 777 | Swap Adjacent in LR String | Medium | To Do | To Do | To Do | To Do |
| 778 | Swim in Rising Water | Hard | To Do | To Do | To Do | To Do |
| 779 | K-th Symbol in Grammar | Medium | To Do | To Do | To Do | To Do |
| 780 | Reaching Points | Hard | To Do | To Do | To Do | To Do |
| 781 | Rabbits in Forest | Medium | To Do | To Do | To Do | To Do |
| 782 | Transform to Chessboard | Hard | To Do | To Do | To Do | To Do |
| 783 | Minimum Distance Between BST Nodes | Easy | To Do | To Do | To Do | To Do |
| 784 | Letter Case Permutation | Easy | To Do | To Do | To Do | To Do |
| 785 | Is Graph Bipartite? | Medium | To Do | To Do | To Do | To Do |
| 786 | K-th Smallest Prime Fraction | Hard | To Do | To Do | To Do | To Do |
| 787 | Cheapest Flights Within K Stops | Medium | To Do | To Do | To Do | To Do |
| 788 | Rotated Digits | Easy | To Do | To Do | To Do | To Do |
| 789 | Escape The Ghosts | Medium | To Do | To Do | To Do | To Do |
| 790 | Domino and Tromino Tiling | Medium | To Do | To Do | To Do | To Do |
| 791 | Custom Sort String | Medium | To Do | To Do | To Do | To Do |
| 792 | Number of Matching Subsequences | Medium | To Do | To Do | To Do | To Do |
| 793 | Preimage Size of Factorial Zeroes Function | Hard | To Do | To Do | To Do | To Do |
| 794 | Valid Tic-Tac-Toe State | Medium | To Do | To Do | To Do | To Do |
| 795 | Number of Subarrays with Bounded Maximum | Medium | To Do | To Do | To Do | To Do |
| 796 | Rotate String | Easy | To Do | To Do | To Do | To Do |
| 797 | All Paths From Source to Target | Medium | To Do | To Do | To Do | To Do |
| 798 | Smallest Rotation with Highest Score | Hard | To Do | To Do | To Do | To Do |
| 799 | Champagne Tower | Medium | To Do | To Do | To Do | To Do |
| 800 | Similar RGB Color 🔒 | Easy | To Do | To Do | To Do | To Do |
| 801 | Minimum Swaps To Make Sequences Increasing | Medium | To Do | To Do | To Do | To Do |
| 802 | Find Eventual Safe States | Medium | To Do | To Do | To Do | To Do |
| 803 | Bricks Falling When Hit | Hard | To Do | To Do | To Do | To Do |
| 804 | Unique Morse Code Words | Easy | To Do | To Do | To Do | To Do |
| 805 | Split Array With Same Average | Hard | To Do | To Do | To Do | To Do |
| 806 | Number of Lines To Write String | Easy | To Do | To Do | To Do | To Do |
| 807 | Max Increase to Keep City Skyline | Medium | To Do | To Do | To Do | To Do |
| 808 | Soup Servings | Medium | To Do | To Do | To Do | To Do |
| 809 | Expressive Words | Medium | To Do | To Do | To Do | To Do |
| 810 | Chalkboard XOR Game | Hard | To Do | To Do | To Do | To Do |
| 811 | Subdomain Visit Count | Easy | To Do | To Do | To Do | To Do |
| 812 | Largest Triangle Area | Easy | To Do | To Do | To Do | To Do |
| 813 | Largest Sum of Averages | Medium | To Do | To Do | To Do | To Do |
| 814 | Binary Tree Pruning | Medium | To Do | To Do | To Do | To Do |
| 815 | Bus Routes | Hard | To Do | To Do | To Do | To Do |
| 816 | Ambiguous Coordinates | Medium | To Do | To Do | To Do | To Do |
| 817 | Linked List Components | Medium | To Do | To Do | To Do | To Do |
| 818 | Race Car | Hard | To Do | To Do | To Do | To Do |
| 819 | Most Common Word | Easy | To Do | To Do | To Do | To Do |
| 820 | Short Encoding of Words | Medium | To Do | To Do | To Do | To Do |
| 821 | Shortest Distance to a Character | Easy | To Do | To Do | To Do | To Do |
| 822 | Card Flipping Game | Medium | To Do | To Do | To Do | To Do |
| 823 | Binary Trees With Factors | Medium | To Do | To Do | To Do | To Do |
| 824 | Goat Latin | Easy | To Do | To Do | To Do | To Do |
| 825 | Friends Of Appropriate Ages | Medium | To Do | To Do | To Do | To Do |
| 826 | Most Profit Assigning Work | Medium | To Do | To Do | To Do | To Do |
| 827 | Making A Large Island | Hard | To Do | To Do | To Do | To Do |
| 828 | Unique Letter String | Hard | To Do | To Do | To Do | To Do |
| 829 | Consecutive Numbers Sum | Medium | To Do | To Do | To Do | To Do |
| 830 | Positions of Large Groups | Easy | To Do | To Do | To Do | To Do |
| 831 | Masking Personal Information | Medium | To Do | To Do | To Do | To Do |
| 832 | Flipping an Image | Easy | To Do | To Do | To Do | To Do |
| 833 | Find And Replace in String | Medium | To Do | To Do | To Do | To Do |
| 834 | Sum of Distances in Tree | Hard | To Do | To Do | To Do | To Do |
| 835 | Image Overlap | Medium | To Do | To Do | To Do | To Do |
| 836 | Rectangle Overlap | Easy | To Do | To Do | To Do | To Do |
| 837 | New 21 Game | Medium | To Do | To Do | To Do | To Do |
| 838 | Push Dominoes | Medium | To Do | To Do | To Do | To Do |
| 839 | Similar String Groups | Hard | To Do | To Do | To Do | To Do |
| 840 | Magic Squares In Grid | Easy | To Do | To Do | To Do | To Do |
| 841 | Keys and Rooms | Medium | To Do | To Do | To Do | To Do |
| 842 | Split Array into Fibonacci Sequence | Medium | To Do | To Do | To Do | To Do |
| 843 | Guess the Word | Hard | To Do | To Do | To Do | To Do |