Python / C++ 11 Solutions of All LeetCode Problems
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- Bit Manipulation
- Array
- String
- Linked List
- Stack
- Queue
- Heap
- Tree
- Hash Table
- Math
- Two Pointers
- Sort
- Recursion
- Binary Search
- Binary Search Tree
- Breadth-First Search
- Depth-First Search
- Backtracking
- Dynamic Programming
- Greedy
- Graph
- Geometry
- Simulation
- Design
- C++
- Python
| # | Title | Solution | Time | Space | Difficulty | Tag | Note |
|---|---|---|---|---|---|---|---|
| 239 | Sliding Window Maximum | C++ Python | O(n) | O(k) | Hard | EPI, LintCode | |
| 281 | Zigzag Iterator | C++ Python | O(n) | O(k) | Medium | 🔒 | |
| 346 | Moving Average from Data Stream | C++ Python | O(1) | O(w) | Easy | 🔒 | |
| 862 | Shortest Subarray with Sum at Least K | C++ Python | O(n) | O(n) | Hard | ||
| 933 | Number of Recent Calls | C++ Python | O(1) on average | O(w) | Easy |
| # | Title | Solution | Time | Space | Difficulty | Tag | Note |
|---|---|---|---|---|---|---|---|
| 264 | Ugly Number II | C++ Python | O(n) | O(1) | Medium | CTCI, LintCode | BST, Heap |
| 295 | Find Median from Data Stream | C++ Python | O(nlogn) | O(n) | Hard | EPI, LintCode | BST, Heap |
| 313 | Super Ugly Number | C++ Python | O(n * k) | O(n + k) | Medium | BST, Heap | |
| 358 | Rearrange String k Distance Apart | C++ Python | O(n) | O(n) | Hard | 🔒 | Greedy, Heap |
| 373 | Find K Pairs with Smallest Sums | C++ Python | O(k * log(min(n, m, k))) | O(min(n, m, k)) | Medium | ||
| 378 | Kth Smallest Element in a Sorted Matrix | C++ Python | O(k * log(min(n, m, k))) | O(min(n, m, k)) | Medium | LintCode | |
| 407 | Trapping Rain Water II | C++ Python | O(m * n * (logm + logn)) | O(m * n) | Hard | LintCode | |
| 632 | Smallest Range | C++ Python | O(nlogk) | O(k) | Hard | ||
| 703 | Kth Largest Element in a Stream | C++ Python | O(nlogk) | O(k) | Easy | ||
| 846 | Hand of Straights | C++ Python | O(nlogn) | O(n) | Medium | ||
| 855 | Exam Room | C++ Python | seat: O(logn) leave: O(logn) |
O(n) | Medium | BST, Hash | |
| 857 | Minimum Cost to Hire K Workers | C++ Python | O(nlogn) | O(n) | Hard | Sort | |
| 871 | Minimum Number of Refueling Stops | C++ Python | O(nlogn) | O(n) | Hard | Sort |
| # | Title | Solution | Time | Space | Difficulty | Tag | Note |
|---|---|---|---|---|---|---|---|
| 056 | Merge Intervals | C++ Python | O(nlogn) | O(1) | Hard | ||
| 057 | Insert Interval | C++ Python | O(n) | O(1) | Hard | ||
| 075 | Sort Colors | C++ Python | O(n) | O(1) | Medium | Tri Partition | |
| 088 | Merge Sorted Array | C++ Python | O(n) | O(1) | Easy | ||
| 147 | Insertion Sort List | C++ Python | O(n^2) | O(1) | Medium | ||
| 148 | Sort List | C++ Python | O(nlogn) | O(logn) | Medium | ||
| 164 | Maximum Gap | C++ Python | O(n) | O(n) | Hard | Tricky | |
| 179 | Largest Number | C++ Python | O(nlogn) | O(1) | Medium | ||
| 218 | The Skyline Problem | C++ Python | O(nlogn) | O(n) | Hard | Sort, BST | |
| 252 | Meeting Rooms | C++ Python | O(nlogn) | O(n) | Easy | 🔒 | |
| 253 | Meeting Rooms II | C++ Python | O(nlogn) | O(n) | Medium | 🔒 | |
| 274 | H-Index | C++ Python | O(n) | O(n) | Medium | Counting Sort | |
| 280 | Wiggle Sort | C++ Python | O(n) | O(1) | Medium | 🔒 | |
| 324 | Wiggle Sort II | C++ Python | O(n) on average | O(1) | Medium | variant of Sort Colors | Tri Partition |
| 347 | Top K Frequent Elements | C++ Python | O(n) | O(n) | Medium | Quick Select, Heap, Bucket Sort | |
| 406 | Queue Reconstruction by Height | C++ Python | O(n * sqrt(n)) | O(n) | Medium | Tricky | |
| 451 | Sort Characters By Frequency | C++ Python | O(n) | O(n) | Medium | ||
| 692 | Top K Frequent Words | C++ Python | O(n + klogk) on average | O(n) | Medium | Quick Select, Heap, Bucket Sort | |
| 937 | Reorder Log Files | C++ Python | O(nlogn * l) | O(l) | Easy | ||
| 969 | Pancake Sorting | C++ Python | O(n^2) | O(l) | Medium | ||
| 973 | K Closest Points to Origin | C++ Python | O(n) on average | O(1) | Easy | Quick Select, Heap | |
| 976 | Largest Perimeter Triangle | C++ Python | O(nlogn) | O(1) | Easy |
| # | Title | Solution | Time | Space | Difficulty | Tag | Note |
|---|---|---|---|---|---|---|---|
| 220 | Contains Duplicate III | C++ Python | O(nlogk) | O(k) | Medium | ||
| 230 | Kth Smallest Element in a BST | C++ Python | O(max(h, k)) | O(min(h, k)) | Medium | ||
| 235 | Lowest Common Ancestor of a Binary Search Tree | C++ Python | O(h) | O(1) | Easy | EPI | |
| 270 | Closest Binary Search Tree Value | C++ Python | O(h) | O(1) | Easy | 🔒 | |
| 285 | Inorder Successor in BST | C++ Python | O(h) | O(1) | Medium | 🔒 | |
| 352 | Data Stream as Disjoint Intervals | C++ Python | O(logn) | O(n) | Hard | ||
| 449 | Serialize and Deserialize BST | C++ Python | O(n) | O(h) | Medium | ||
| 450 | Delete Node in a BST | C++ Python | O(h) | O(h) | Medium | ||
| 530 | Minimum Absolute Difference in BST | C++ Python | O(n) | O(h) | Easy | ||
| 776 | Split BST | C++ Python | O(n) | O(h) | Medium | 🔒 | |
| 783 | Minimum Distance Between BST Nodes | C++ Python | O(n) | O(h) | Easy | ||
| 510 | Inorder Successor in BST II | C++ Python | O(h) | O(1) | Medium | 🔒 |
| # | Title | Solution | Time | Space | Difficulty | Tag | Note |
|---|---|---|---|---|---|---|---|
| 102 | Binary Tree Level Order Traversal | C++ Python | O(n) | O(n) | Easy | ||
| 107 | Binary Tree Level Order Traversal II | Python | O(n) | O(n) | Easy | ||
| 103 | Binary Tree Zigzag Level Order Traversal | Python | O(n) | O(n) | Medium | ||
| 117 | Populating Next Right Pointers in Each Node II | Python | O(n) | O(1) | Hard | ||
| 127 | Word Ladder | Python | O(n * d) | O(d) | Medium | ||
| 130 | Surrounded Regions | C++ Python | O(m * n) | O(m + n) | Medium | ||
| 133 | Clone Graph | Python | O(n) | O(n) | Medium | ||
| 207 | Course Schedule | Python | O(|V| + |E|) | O(|E|) | Medium | Topological Sort | |
| 210 | Course Schedule II | Python | O(|V| + |E|) | O(|E|) | Medium | Topological Sort | |
| 261 | Graph Valid Tree | C++ Python | O(|V| + |E|) | O(|V| + |E|) | Medium | 🔒 | |
| 269 | Alien Dictionary | C++ Python | O(n) | O(1) | Hard | 🔒 | Topological Sort, BFS, DFS |
| 286 | Walls and Gates | C++ Python | O(m * n) | O(g) | Medium | 🔒 | |
| 310 | Minimum Height Trees | C++ Python | O(n) | O(n) | Medium | ||
| 317 | Shortest Distance from All Buildings | C++ Python | O(k * m * n) | O(m * n) | Hard | 🔒 | |
| 433 | Minimum Genetic Mutation | C++ Python | O(n * b) | O(b) | Medium | ||
| 444 | Sequence Reconstruction | C++ Python | O(n * s) | O(n) | Medium | 🔒 | Topological Sort |
| 490 | The Maze | C++ Python | O(max(r, c) * w) | O(w) | Medium | ||
| 499 | The Maze III | C++ Python | O(max(r, c) * wlogw) | O(w^2) | Hard | ||
| 505 | The Maze II | C++ Python | O(max(r, c) * wlogw) | O(w) | Medium | ||
| 542 | 01 Matrix | C++ Python | O(m * n) | O(m * n) | Medium | DP | |
| 666 | Path Sum IV | C++ Python | O(n) | O(w) | Medium | 🔒 | Topological Sort |
| 675 | Cut Off Trees for Golf Event | C++ Python | O(t * m * n) | O(m * n) | Hard | A* Search Algorithm |
|
| 742 | Closest Leaf in a Binary Tree | C++ Python | O(n) | O(n) | Medium | ||
| 743 | Network Delay Time | C++ Python | O(|E| * log|V|) | O(|E|) | Medium | Dijkstra's algorithm |
|
| 752 | Open the Lock | C++ Python | O(k * n^k + d) | O(k * n^k + d) | Medium | ||
| 773 | Sliding Puzzle | C++ Python | O((m * n) * (m * n)!) | O((m * n) * (m * n)!) | Hard | A* Search Algorithm |
|
| 787 | Cheapest Flights Within K Stops | C++ Python | O(|E| * log|V|) | O(|E|) | Medium | Dijkstra's algorithm |
|
| 815 | Bus Routes | C++ Python | O(|E| + |V|) | O(|E| + |V|) | Hard | ||
| 854 | K-Similar Strings | C++ Python | O(n * n!/(c_a!*...*c_z!)) | O(n * n!/(c_a!*...*c_z!)) | Hard | ||
| 865 | Shortest Path to Get All Keys | C++ Python | O(k * r * c + k^3*2^k) | O(k*2^k) | Hard | Dijkstra's algorithm |
|
| 882 | Reachable Nodes In Subdivided Graph | C++ Python | O(|E| * log|V|) | O(|E|) | Hard | Dijkstra's algorithm |
|
| 886 | Possible Bipartition | C++ Python | O(|V| + |E|) | O(|V| + |E|) | Medium | ||
| 934 | Shortest Bridge | C++ Python | O(n^2) | O(n^2) | Medium | BFS, DFS | |
| 967 | Numbers With Same Consecutive Differences | C++ Python | O(2^n) | O(2^n) | Medium |
| # | Title | Solution | Time | Space | Difficulty | Tag | Note |
|---|---|---|---|---|---|---|---|
| 112 | Path Sum | Python | O(n) | O(h) | Easy | ||
| 113 | Path Sum II | Python | O(n) | O(h) | Medium | ||
| 199 | Binary Tree Right Side View | Python | O(n) | O(h) | Medium | ||
| 200 | Number of Islands | Python | O(m * n) | O(m * n) | Medium | ||
| 236 | Lowest Common Ancestor of a Binary Tree | C++ Python | O(n) | O(h) | Medium | EPI | |
| 247 | Strobogrammatic Number II | C++ Python | O(n^2 * 5^(n/2)) | O(n) | Medium | 🔒 | |
| 250 | Count Univalue Subtrees | C++ Python | O(n) | O(h) | Medium | 🔒 | |
| 257 | Binary Tree Paths | C++ Python | O(n * h) | O(h) | Easy | ||
| 282 | Expression Add Operators | C++ Python | O(4^n) | O(n) | Hard | ||
| 301 | Remove Invalid Parentheses | C++ Python | O(C(n, c)) | O(c) | Hard | ||
| 329 | Longest Increasing Path in a Matrix | C++ Python | O(m * n) | O(m * n) | Hard | ||
| 332 | Reconstruct Itinerary | C++ Python | O(t! / (n1! * n2! * ... nk!)) | O(t) | Medium | ||
| 339 | Nested List Weight Sum | C++ Python | O(n) | O(h) | Easy | 🔒 | |
| 364 | Nested List Weight Sum II | C++ Python | O(n) | O(h) | Medium | 🔒 | |
| 366 | Find Leaves of Binary Tree | C++ Python | O(n) | O(h) | Medium | 🔒 | |
| 399 | Evaluate Division | C++ Python | O(q * |V|!) | O(e) | Medium | ||
| 417 | Pacific Atlantic Water Flow | C++ Python | O(m * n) | O(m * n) | Medium | ||
| 440 | K-th Smallest in Lexicographical Order | C++ Python | O(logn) | O(logn) | Hard | ||
| 464 | Can I Win | C++ Python | O(n!) | O(n) | Medium | ||
| 515 | Find Largest Value in Each Tree Row | C++ Python | O(n) | O(h) | Medium | ||
| 547 | Friend Circles | C++ Python | O(n^2) | O(n) | Medium | Union Find | |
| 582 | Kill Process | C++ Python | O(n) | O(n) | Medium | 🔒 | DFS, BFS |
| 638 | Shopping Offers | C++ Python | O(n * 2^n) | O(n) | Medium | ||
| 690 | Employee Importance | C++ Python | O(n) | O(h) | Easy | DFS, BFS | |
| 694 | Number of Distinct Islands | C++ Python | O(m * n) | O(m * n) | Medium | 🔒 | |
| 695 | Max Area of Island | C++ Python | O(m * n) | O(m * n) | Easy | ||
| 711 | Number of Distinct Islands II | C++ Python | O((m * n) * log(m * n)) | O(m * n) | Hard | 🔒 | Hash |
| 733 | Max Area of Island | C++ Python | O(m * n) | O(m * n) | Easy | ||
| 749 | Contain Virus | C++ Python | O((m * n)^(4/3)) | O(m * n) | Hard | Simulation | |
| 753 | Cracking the Safe | C++ Python | O(k^n) | O(k^n) | Hard | de Bruijn sequences, Lyndon word |
|
| 756 | Pyramid Transition Matrix | C++ Python | O(a^b) | O(a^b) | Medium | ||
| 785 | Is Graph Bipartite? | C++ Python | O(|V| + |E|) | O(|V|) | Medium | ||
| 797 | All Paths From Source to Target | C++ Python | O(p + r * n) | O(n) | Medium | ||
| 802 | Find Eventual Safe States | C++ Python | O(|V| + |E|) | O(|V|) | Medium | ||
| 827 | Making A Large Island | C++ Python | O(n^2) | O(n^2) | Hard | ||
| 834 | Sum of Distances in Tree | C++ Python | O(n) | O(n) | Hard | ||
| 841 | Keys and Rooms | C++ Python | O(n!) | O(n) | Medium | ||
| 851 | Loud and Rich | C++ Python | O(q + r) | O(q + r) | Medium | ||
| 913 | Cat and Mouse | C++ Python | O(n^3) | O(n^2) | Hard |
| # | Title | Solution | Time | Space | Difficulty | Tag | Note |
|---|---|---|---|---|---|---|---|
| 017 | Letter Combinations of a Phone Number | Python | O(n * 4^n) | O(n) | Medium | ||
| 022 | Generate Parentheses | Python | O(4^n / n^(3/2)) | O(n) | Medium | ||
| 037 | Sudoku Solver | Python | O((9!)^9) | O(1) | Hard | ||
| 039 | Combination Sum | Python | O(k * n^k) | O(k) | Medium | ||
| 040 | Combination Sum II | Python | O(k * C(n, k)) | O(k) | Medium | ||
| 046 | Permutations | Python | O(n * n!) | O(n) | Medium | ||
| 047 | Permutations II | Python | O(n * n!) | O(n) | Medium | ||
| 051 | N-Queens | Python | O(n!) | O(n) | Hard | ||
| 052 | N-Queens-II | Python | O(n!) | O(n) | Hard | ||
| 077 | Combinations | Python | O(O(k * C(n, k))) | O(k) | Medium | ||
| 079 | Word Search | Python | O(m * n * l) | O(l) | Medium | ||
| 093 | Restore IP Addresses | Python | O(1) | O(1) | Medium | ||
| 078 | Subsets | C++ Python | O(n * 2^n) | O(1) | Medium | ||
| 090 | Subsets II | C++ Python | O(n * 2^n) | O(1) | Medium | ||
| 126 | Word Ladder II | Python | O(n * d) | O(d) | Hard | ||
| 131 | Palindrome Partitioning | Python | O(n^2) ~ O(2^n) | O(n^2) | Medium | ||
| 140 | Word Break II | C++ Python | O(n * l^2 + n * r) | O(n^2) | Hard | ||
| 212 | Word Search II | C++ Python | O(m * n * l) | O(l) | Hard | LintCode | Trie, DFS |
| 216 | Combination Sum III | C++ Python | O(k * C(n, k)) | O(k) | Medium | ||
| 254 | Factor Combinations | C++ Python | O(nlogn) | O(logn) | Medium | 🔒 | |
| 267 | Palindrome Permutation II | C++ Python | O(n * n!) | O(n) | Medium | 🔒 | |
| 291 | Word Pattern II | C++ Python | O(n * C(n - 1, c - 1)) | O(n + c) | Hard | 🔒 | |
| 294 | Flip Game II | C++ Python | O(n + c^2) | O(c) | Medium | 🔒 | DP, Hash |
| 320 | Generalized Abbreviation | C++ Python | O(n * 2^n) | O(n) | Medium | 🔒 | |
| 425 | Word Squares | C++ Python | O(n^2 * n!) | O(n^2) | Hard | 🔒 | |
| 526 | Beautiful Arrangement | C++ Python | O(n!) | O(n) | Medium | ||
| 676 | Implement Magic Dictionary | C++ Python | O(n) | O(d) | Medium | Trie, DFS | |
| 679 | 24 Game | C++ Python | O(1) | O(1) | Hard | DFS | |
| 698 | Partition to K Equal Sum Subsets | C++ Python | O(n * 2^n) | O(2^n) | Medium | DFS, DP, Memoization | |
| 718 | Maximum Length of Repeated Subarray | C++ Python | O(m * n) | O(min(m, n)) | Medium | DP, Hash, Binary Search | |
| 784 | Letter Case Permutation | C++ Python | O(n * 2^n) | O(1) | Easy |
| # | Title | Solution | Time | Space | Difficulty | Tag | Note |
|---|---|---|---|---|---|---|---|
| 010 | Regular Expression Matching | Python | O(m * n) | O(n) | Hard | ||
| 044 | Wildcard Matching | Python | O(m * n) | O(1) | Hard | Greedy | |
| 053 | Maximum Subarray | Python | O(n) | O(1) | Medium | ||
| 062 | Unique Paths | Python | O(m * n) | O(m + n) | Medium | ||
| 063 | Unique Paths II | Python | O(m * n) | O(m + n) | Medium | ||
| 064 | Minimum Path Sum | Python | O(m * n) | O(m + n) | Medium | ||
| 070 | Climbing Stairs | C++ Python | O(logn) | O(1) | Easy | Matrix Exponentiation | |
| 072 | Edit Distance | Python | O(m * n) | O(m + n) | Hard | ||
| 087 | Scramble String | Python | O(n^4) | O(n^3) | Hard | ||
| 091 | Decode Ways | C++ Python | O(n) | O(1) | Medium | ||
| 096 | Unique Binary Search Trees | Python | O(n) | O(1) | Medium | Math | |
| 097 | Interleaving String | Python | O(m * n) | O(m + n) | Hard | ||
| 115 | Distinct Subsequences | Python | O(n^2) | O(n) | Hard | ||
| 120 | Triangle | Python | O(m * n) | O(n) | Medium | ||
| 123 | Best Time to Buy and Sell Stock III | Python | O(n) | O(1) | Hard | ||
| 132 | Palindrome Partitioning II | Python | O(n^2) | O(n^2) | Hard | ||
| 139 | Word Break | C++ Python | O(n * l^2) | O(n) | Medium | ||
| 152 | Maximum Product Subarray | Python | O(n) | O(1) | Medium | ||
| 174 | Dungeon Game | Python | O(m * n) | O(m + n) | Hard | ||
| 188 | Best Time to Buy and Sell Stock IV | Python | O(k * n) | O(k) | Hard | ||
| 198 | House Robber | C++ Python | O(n) | O(1) | Easy | ||
| 213 | House Robber II | C++ Python | O(n) | O(1) | Medium | ||
| 221 | Maximal Square | C++ Python | O(n^2) | O(n) | Medium | EPI | |
| 256 | Paint House | C++ Python | O(n) | O(1) | Medium | 🔒 | |
| 265 | Paint House II | C++ Python | O(n * k) | O(k) | Hard | 🔒 | |
| 276 | Paint Fence | C++ Python | O(n) | O(1) | Easy | 🔒 | |
| 279 | Perfect Squares | C++ Python | O(n * sqrt(n)) | O(n) | Medium | Hash | |
| 303 | Range Sum Query - Immutable | C++ Python | ctor: O(n), lookup: O(1) | O(n) | Easy | ||
| 304 | Range Sum Query 2D - Immutable | C++ Python | ctor: O(m * n), lookup: O(1) | O(m * n) | Medium | ||
| 309 | Best Time to Buy and Sell Stock with Cooldown | C++ Python | O(n) | O(1) | Medium | ||
| 312 | Burst Balloons | C++ Python | O(n^3) | O(n^2) | Hard | ||
| 322 | Coin Change | C++ Python | O(n * k) | O(k) | Medium | ||
| 351 | Android Unlock Patterns | C++ Python | O(9^2 * 2^9) | O(9 * 2^9) | Medium | 🔒 | Backtracking |
| 357 | Count Numbers with Unique Digits | C++ Python | O(n) | O(1) | Medium | Backtracking, Math | |
| 361 | Bomb Enemy | C++ Python | O(m * n) | O(m * n) | Medium | 🔒 | |
| 368 | Largest Divisible Subset | C++ Python | O(n^2) | O(n) | Medium | ||
| 375 | Guess Number Higher or Lower II | C++ Python | O(n^2) | O(n^2) | Medium | ||
| 377 | Combination Sum IV | C++ Python | O(nlogn + n * t) | O(t) | Medium | ||
| 403 | Frog Jump | C++ Python | O(n) | O(n) ~ O(n^2) | Hard | ||
| 416 | Partition Equal Subset Sum | C++ Python | O(n * s) | O(s) | Medium | ||
| 418 | Sentence Screen Fitting | C++ Python | O(r + n * c) | O(n) | Medium | 🔒 | |
| 446 | Arithmetic Slices II - Subsequence | C++ Python | O(n^2) | O(n * d) | Hard | ||
| 465 | Optimal Account Balancing | C++ Python | O(n * 2^n) | O(n * 2^n) | Hard | 🔒 | |
| 466 | Count The Repetitions | C++ Python | O(s1 * min(s2, n1)) | O(s2) | Hard | ||
| 467 | Unique Substrings in Wraparound String | C++ Python | O(n) | O(1) | Medium | ||
| 471 | Encode String with Shortest Length | C++ Python | O(n^3) on average | O(n^2) | Medium | 🔒 | |
| 472 | Concatenated Words | C++ Python | O(n * l^2) | O(n * l) | Medium | ||
| 474 | Ones and Zeroes | C++ Python | O(s * m * n) | O(m * n) | Medium | ||
| 486 | Predict the Winner | C++ Python | O(n^2) | O(n) | Medium | ||
| 509 | Fibonacci Number | C++ Python | O(logn) | O(1) | Easy | variant of Climbing Stairs | Matrix Exponentiation |
| 514 | Freedom Trail | C++ Python | O(k) ~ O(k * r^2) | O(r) | Hard | ||
| 516 | Longest Palindromic Subsequence | C++ Python | O(n^2) | O(n) | Medium | ||
| 546 | Remove Boxes | C++ Python | O(n^3) ~ O(n^4) | O(n^3) | Hard | ||
| 552 | Student Attendance Record II | C++ Python | O(n) | O(1) | Hard | ||
| 562 | Longest Line of Consecutive One in Matrix | C++ Python | O(m * n) | O(n) | Medium | 🔒 | |
| 568 | Maximum Vacation Days | C++ Python | O(n^2 * k) | O(k) | Hard | 🔒 | |
| 576 | Out of Boundary Paths | C++ Python | O(N * m * n) | O(m * n) | Medium | ||
| 583 | Delete Operation for Two Strings | C++ Python | O(m * n) | O(n) | Medium | ||
| 600 | Non-negative Integers without Consecutive Ones | C++ Python | O(1) | O(1) | Hard | ||
| 629 | K Inverse Pairs Array | C++ Python | O(n * k) | O(k) | Hard | ||
| 639 | Decode Ways II | C++ Python | O(n) | O(1) | Hard | ||
| 650 | 2 Keys Keyboard | C++ Python | O(sqrt(n)) | O(1) | Medium | ||
| 656 | Coin Path | C++ Python | O(n * B) | O(n) | Hard | 🔒 | |
| 664 | Strange Printer | C++ Python | O(n^3) | O(n^2) | Hard | ||
| 673 | Number of Longest Increasing Subsequence | C++ Python | O(n^2) | O(n) | Medium | ||
| 688 | Knight Probability in Chessboard | C++ Python | O(k * n^2) | O(n^2) | Medium | ||
| 689 | Maximum Sum of 3 Non-Overlapping Subarrays | C++ Python | O(n) | O(n) | Hard | ||
| 691 | Stickers to Spell Word | C++ Python | O(T * S^T) | O(T * S^T) | Hard | Backtracking, Memoization | |
| 712 | Minimum ASCII Delete Sum for Two Strings | C++ Python | O(m * n) | O(n) | Medium | ||
| 714 | Best Time to Buy and Sell Stock with Transaction Fee | C++ Python | O(n) | O(1) | Medium | ||
| 727 | Minimum Window Subsequence | C++ Python | O(s * t) | O(s) | Hard | 🔒 | |
| 730 | Count Different Palindromic Subsequences | C++ Python | O(n^2) | O(n) | Hard | ||
| 740 | Delete and Earn | C++ Python | O(n) | O(1) | Medium | ||
| 741 | Cherry Pickup | C++ Python | O(n^3) | O(n^2) | Hard | ||
| 746 | Min Cost Climbing Stairs | C++ Python | O(n) | O(1) | Easy | ||
| 750 | Number Of Corner Rectangles | C++ Python | O(n * m^2) | O(n * m) | Medium | ||
| 764 | Largest Plus Sign | C++ Python | O(n^2) | O(n^2) | Medium | ||
| 788 | Rotated Digits | C++ Python | O(logn) | O(logn) | Easy | Memoization | |
| 790 | Domino and Tromino Tiling | C++ Python | O(logn) | O(1) | Medium | Matrix Exponentiation | |
| 799 | Champagne Tower | C++ Python | O(n^2) | O(n) | Medium | ||
| 801 | Minimum Swaps To Make Sequences Increasing | C++ Python | O(n) | O(1) | Medium | ||
| 805 | Split Array With Same Average | C++ Python | O(n^4) | O(n^3) | Hard | ||
| 808 | Soup Servings | C++ Python | O(1) | O(1) | Medium | Memoization | |
| 813 | Largest Sum of Averages | C++ Python | O(k * n^2) | O(n) | Medium | ||
| 818 | Race Car | C++ Python | O(nlogn) | O(n) | Hard | ||
| 823 | Binary Trees With Factors | C++ Python | O(n^2) | O(n) | Medium | ||
| 837 | New 21 Game | C++ Python | O(n) | O(n) | Medium | ||
| 838 | Push Dominoes | C++ Python | O(n) | O(n) | Medium | ||
| 847 | Shortest Path Visiting All Nodes | C++ Python | O(n *2^n) | O(n * 2^n) | Hard | BFS | |
| 877 | Stone Game | C++ Python | O(n^2) | O(n) | Medium | variant of Predict the Winner | |
| 879 | Profitable Schemes | C++ Python | O(n * p * g) | O(p * g) | Hard | ||
| 903 | Valid Permutations for DI Sequence | C++ Python | O(n^2) | O(n) | Hard | ||
| 920 | Number of Music Playlists | C++ Python | O(n * l) | O(l) | Hard | ||
| 926 | Flip String to Monotone Increasing | C++ Python | O(n) | O(1) | Medium | ||
| 931 | Minimum Falling Path Sum | C++ Python | O(n^2) | O(1) | Medium | ||
| 935 | Knight Dialer | C++ Python | O(logn) | O(1) | Medium | Matrix Exponentiation | |
| 940 | Distinct Subsequences II | C++ Python | O(n) | O(1) | Hard | ||
| 943 | Find the Shortest Superstring | C++ Python | O(n^2 * (l^2 + 2^n)) | O(n^2) | Hard | ||
| 956 | Tallest Billboard | C++ Python | O(n * 3^(n/2)) | O(3^(n/2)) | Hard | ||
| 960 | Delete Columns to Make Sorted III | C++ Python | O(n * l^2) | O(l) | Hard | ||
| 964 | Least Operators to Express Number | C++ Python | O(logn / logx) | O(logn) | Hard | Math | |
| 975 | Odd Even Jump | C++ Python | O(nlogn) | O(n) | Hard | Descending Stack, BST | |
| 980 | Unique Paths III | C++ Python | O((m * n) * 2^(m * n)) | O((m * n) * 2^(m * n)) | Hard | ||
| 983 | Minimum Cost For Tickets | C++ Python | O(n) | O(1) | Medium |
| # | Title | Solution | Time | Space | Difficulty | Tag | Note |
|---|---|---|---|---|---|---|---|
| 011 | Container With Most Water | C++ Python | O(n) | O(1) | Medium | ||
| 042 | Trapping Rain Water | C++ Python | O(n) | O(1) | Hard | Tricky | |
| 045 | Jump Game II | Python | O(n) | O(1) | Hard | ||
| 055 | Jump Game | Python | O(n) | O(1) | Medium | ||
| 122 | Best Time to Buy and Sell Stock II | C++ Python | O(n) | O(1) | Easy | ||
| 134 | Gas Station | Python | O(n) | O(1) | Medium | ||
| 135 | Candy | C++ Python | O(n) | O(n) | Hard | ||
| 316 | Remove Duplicate Letters | C++ Python | O(n) | O(k) | Hard | Ascending Stack | |
| 321 | Create Maximum Number | C++ Python | O(k * (m + n + k)) ~ O(k * (m + n + k^2)) | O(m + n + k^2) | Hard | variant of Delete Digits | Greedy, DP |
| 330 | Patching Array | C++ Python | O(s + logn) | O(1) | Hard | ||
| 376 | Wiggle Subsequence | C++ Python | O(n) | O(1) | Medium | ||
| 392 | Is Subsequence | C++ Python | O(n) | O(1) | Medium | ||
| 397 | Integer Replacement | C++ Python | O(n) | O(1) | Medium | Math | |
| 402 | Remove K Digits | C++ Python | O(n) | O(n) | Medium | LintCode | |
| 435 | Non-overlapping Intervals | C++ Python | O(nlogn) | O(1) | Medium | Line Sweep | |
| 452 | Minimum Number of Arrows to Burst Balloons | C++ Python | O(nlogn) | O(1) | Medium | ||
| 455 | Assign Cookies | C++ Python | O(nlogn) | O(1) | Easy | ||
| 621 | Task Scheduler | C++ Python | O(n) | O(1) | Medium | ||
| 630 | Course Schedule III | C++ Python | O(nlogn) | O(k) | Hard | ||
| 646 | Maximum Length of Pair Chain | C++ Python | O(nlogn) | O(1) | Medium | similar to Non-overlapping Intervals | Line Sweep |
| 649 | Dota2 Senate | C++ Python | O(n) | O(n) | Medium | ||
| 659 | Split Array into Consecutive Subsequences | C++ Python | O(n) | O(1) | Medium | ||
| 738 | Monotone Increasing Digits | C++ Python | O(1) | O(1) | Medium | ||
| 757 | Set Intersection Size At Least Two | C++ Python | O(nlogn) | O(n) | Hard | ||
| 759 | Employee Free Time | C++ Python | O(m * logn) | O(n) | Hard | ||
| 763 | Partition Labels | C++ Python | O(n) | O(n) | Medium | ||
| 767 | Reorganize String | C++ Python | O(n) | O(1) | Medium | ||
| 798 | Smallest Rotation with Highest Score | C++ Python | O(n) | O(1) | Hard | ||
| 843 | Guess the Word | C++ Python | O(n^2) | O(n) | Hard | MinMax | |
| 861 | Score After Flipping Matrix | C++ Python | O(r * c) | O(1) | Medium | ||
| 870 | Advantage Shuffle | C++ Python | O(nlogn) | O(n) | Medium | ||
| 881 | Boats to Save People | C++ Python | O(nlogn) | O(n) | Medium | ||
| 936 | Stamping The Sequence | C++ Python | O((n - m) * m) | O((n - m) * m) | Hard | ||
| 948 | Bag of Tokens | C++ Python | O(nlogn) | O(1) | Medium | Two Pointers | |
| 962 | Maximum Width Ramp | C++ Python | O(n) | O(n) | Medium | Descending Stack | |
| 968 | Binary Tree Cameras | C++ Python | O(n) | O(h) | Hard | DFS | |
| 984 | String Without AAA or BBB | C++ Python | O(a + b) | O(1) | Easy | ||
| 991 | Broken Calculator | C++ Python | O(logn) | O(1) | Medium |
| # | Title | Solution | Time | Space | Difficulty | Tag | Note |
|---|---|---|---|---|---|---|---|
| 765 | Couples Holding Hands | C++ Python | O(n) | O(n) | Hard | ||
| 924 | Minimize Malware Spread | C++ Python | O(n^2) | O(n) | Hard | Union Find | |
| 928 | Minimize Malware Spread II | C++ Python | O(n^2) | O(n) | Hard | Union Find | |
| 959 | Regions Cut By Slashes | C++ Python | O(n^2) | O(n^2) | Medium | Union Find | |
| 959 | Regions Cut By Slashes | C++ Python | O(n^2) | O(n^2) | Medium | Union Find | |
| 990 | Satisfiability of Equality Equations | C++ Python | O(n) | O(1) | Medium | Union Find |
| # | Title | Solution | Time | Space | Difficulty | Tag | Note |
|---|---|---|---|---|---|---|---|
| 587 | Erect the Fence | C++ Python | O(nlogn) | O(n) | Hard | Monotone Chain |
|
| 892 | Surface Area of 3D Shapes | C++ Python | O(n^2) | O(1) | Easy |
| # | Title | Solution | Time | Space | Difficulty | Tag | Note |
|---|---|---|---|---|---|---|---|
| 874 | Walking Robot Simulation | C++ Python | O(n + k) | O(k) | Easy |
| # | Title | Solution | Time | Space | Difficulty | Tag | Note |
|---|---|---|---|---|---|---|---|
| 146 | LRU Cache | C++ Python | O(1) | O(k) | Hard | ||
| 225 | Implement Stack using Queues | C++ Python | push: O(n), pop: O(1), top: O(1) | O(n) | Easy | ||
| 284 | Peeking Iterator | C++ Python | O(1) | O(1) | Medium | ||
| 348 | Design Tic-Tac-Toe | C++ Python | O(1) | O(n^2) | Medium | 🔒 | |
| 353 | Design Snake Game | C++ Python | O(1) | O(s) | Medium | 🔒 | Deque |
| 355 | Design Twitter | C++ Python | O(klogu) | O(t + f) | Medium | LintCode | Heap |
| 359 | Logger Rate Limiter | C++ Python | O(1), amortized | O(k) | Easy | 🔒 | Deque |
| 362 | Design Hit Counter | C++ Python | O(1), amortized | O(k) | Medium | 🔒 | Deque |
| 379 | Design Phone Directory | C++ Python | O(1) | O(n) | Medium | 🔒 | |
| 380 | Insert Delete GetRandom O(1) | C++ Python | O(1) | O(n) | Hard | ||
| 381 | Insert Delete GetRandom O(1) - Duplicates allowed | C++ Python | O(1) | O(n) | Hard | ||
| 432 | All O`one Data Structure | C++ Python | O(1) | O(n) | Hard | ||
| 460 | LFU Cache | C++ Python | O(1) | O(k) | Hard | ||
| 535 | Encode and Decode TinyURL | C++ Python | O(1) | O(n) | Medium | ||
| 588 | Design In-Memory File System | C++ Python | ls: O(l + klogk) mkdir: O(l) addContentToFile: O(l + c) readContentFromFile: O(l + c) |
O(n + s) | Hard | 🔒 | |
| 604 | Design Compressed String Iterator | C++ Python | O(1) | O(1) | Easy | 🔒 | |
| 631 | Design Excel Sum Formula | C++ Python | set: O((r * c)^2) get: O(1) sum: O((r * c)^2) |
O(r * c) | Hard | 🔒 | |
| 635 | Design Log Storage System | C++ Python | put: O(1) retrieve: O(n + dlogd) |
O(n) | Medium | 🔒 | |
| 642 | Design Search Autocomplete System | C++ Python | O(p^2) | O(p * t + s) | Hard | 🔒 | |
| 715 | Range Module | C++ Python | add: O(n) remove: O(n) query: O(logn) |
O(n) | Hard | ||
| 716 | Max Stack | C++ Python | push: O(logn) pop: O(logn) popMax: O(logn) top: O(1) peekMax: O(1) |
O(n) | Easy | ||
| 745 | Prefix and Suffix Search | C++ Python | ctor: O(w * l^2) search : O(p + s) |
O(t) | Hard | Trie | |
| 900 | RLE Iterator | C++ Python | O(n) | O(1) | Medium |
| # | Title | Solution | Time | Space | Difficulty | Tag | Note |
|---|---|---|---|---|---|---|---|
| 175 | Combine Two Tables | MySQL | O(m + n) | O(m + n) | Easy | ||
| 176 | Second Highest Salary | MySQL | O(n) | O(1) | Easy | ||
| 177 | Nth Highest Salary | MySQL | O(n^2) | O(n) | Medium | ||
| 178 | Rank Scores | MySQL | O(n^2) | O(n) | Medium | ||
| 180 | Consecutive Numbers | MySQL | O(n) | O(n) | Medium | ||
| 181 | Employees Earning More Than Their Managers | MySQL | O(n^2) | O(1) | Easy | ||
| 182 | Duplicate Emails | MySQL | O(n^2) | O(n) | Easy | ||
| 183 | Customers Who Never Order | MySQL | O(n^2) | O(1) | Easy | ||
| 184 | Department Highest Salary | MySQL | O(n^2) | O(n) | Medium | ||
| 185 | Department Top Three Salaries | MySQL | O(n^2) | O(n) | Hard | ||
| 196 | Delete Duplicate Emails | MySQL | O(n^2) | O(n) | Easy | ||
| 197 | Rising Temperature | MySQL | O(n^2) | O(n) | Easy | ||
| 262 | Trips and Users | MySQL | O((t * u) + tlogt) | O(t) | Hard |
| # | Title | Solution | Time | Space | Difficulty | Tag | Note |
|---|---|---|---|---|---|---|---|
| 192 | Word Frequency | Shell | O(n) | O(k) | Medium | ||
| 193 | Valid Phone Numbers | Shell | O(n) | O(1) | Easy | ||
| 194 | Transpose File | Shell | O(n^2) | O(n^2) | Medium | ||
| 195 | Tenth Line | Shell | O(n) | O(1) | Easy |