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leetcode https://ttzztt.gitbooks.io/lc/sort/bucket-sort/campus-bikes.html  cn https://ttzztt.gitbooks.io/lc/sort/bucket-sort/campus-bikes.html  Search https://ttzztt.gitbooks.io/lc/sort/bucket-sort/campus-bikes.html

leetcode 946 Validate Stack Sequences Medium  cn 946  Search 946

leetcode 482 License Key Formatting Easy  cn 482  Search 482

leetcode 1320 Minimum Distance to Type a Word Using Two Fingers Hard  cn 1320  Search 1320

leetcode 951 Flip Equivalent Binary Trees Medium  cn 951  Search 951

leetcode 835 Image Overlap Medium  cn 835  Search 835

leetcode 248 Strobogrammatic Number III Hard  cn 248  Search 248

leetcode 1292 Maximum Side Length of a Square with Sum Less than or Equal to Threshold Medium  cn 1292  Search 1292

leetcode 947 Most Stones Removed with Same Row or Column Medium  cn 947  Search 947

leetcode 729 My Calendar I Medium  cn 729  Search 729

leetcode 528 Random Pick with Weight Medium  cn 528  Search 528

leetcode 1032 Stream of Characters Hard  cn 1032  Search 1032

leetcode 924 Minimize Malware Spread Hard  cn 924  Search 924

leetcode 593 Valid Square Medium  cn 593  Search 593

leetcode 862 Shortest Subarray with Sum at Least K Hard  cn 862  Search 862

leetcode 743 Network Delay Time Medium  cn 743  Search 743

leetcode 1011 Capacity To Ship Packages Within D Days Medium  cn 1011  Search 1011

leetcode 1048 Longest String Chain Medium  cn 1048  Search 1048

leetcode 336 Palindrome Pairs Hard  cn 336  Search 336

leetcode 726 Number of Atoms Hard  cn 726  Search 726

leetcode 889 Construct Binary Tree from Preorder and Postorder Traversal Medium  cn 889  Search 889

leetcode 57 Insert Interval Hard  cn 57  Search 57

leetcode 1284 Minimum Number of Flips to Convert Binary Matrix to Zero Matrix Hard  cn 1284  Search 1284

leetcode 295 Find Median from Data Stream Hard  cn 295  Search 295

leetcode 1219 Path with Maximum Gold Medium  cn 1219  Search 1219

leetcode 399 Evaluate Division Medium  cn 399  Search 399

leetcode 1031 Maximum Sum of Two Non-Overlapping Subarrays Medium  cn 1031  Search 1031

leetcode 853 Car Fleet Medium  cn 853  Search 853

leetcode 329 Longest Increasing Path in a Matrix Hard  cn 329  Search 329

leetcode 1197 Minimum Knight Moves Medium  cn 1197  Search 1197

leetcode 774 Minimize Max Distance to Gas Station Hard  cn 774  Search 774

leetcode 913 Cat and Mouse Hard  cn 913  Search 913

leetcode 1203 Sort Items by Groups Respecting Dependencies Hard  cn 1203  Search 1203

leetcode 459 Repeated Substring Pattern Easy  cn 459  Search 459

leetcode 1087 Brace Expansion Medium  cn 1087  Search 1087

leetcode 1240 Tiling a Rectangle with the Fewest Squares Hard  cn 1240  Search 1240

leetcode 369 Plus One Linked List Medium  cn 369  Search 369

leetcode 1096 Brace Expansion II Hard  cn 1096  Search 1096

leetcode 76 Minimum Window Substring Hard  cn 76  Search 76

leetcode 737 Sentence Similarity II Medium  cn 737  Search 737

leetcode 844 Backspace String Compare Easy  cn 844  Search 844

leetcode 767 Reorganize String Medium  cn 767  Search 767

leetcode 632 Smallest Range Covering Elements from K Lists Hard  cn 632  Search 632

leetcode 914 X of a Kind in a Deck of Cards Easy  cn 914  Search 914

leetcode 304 Range Sum Query 2D - Immutable Medium  cn 304  Search 304

leetcode 833 Find And Replace in String Medium  cn 833  Search 833

leetcode 56 Merge Intervals Medium  cn 56  Search 56

leetcode 925 Long Pressed Name Easy  cn 925  Search 925

leetcode 777 Swap Adjacent in LR String Medium  cn 777  Search 777

leetcode 722 Remove Comments Medium  cn 722  Search 722

leetcode 1157 Online Majority Element In Subarray Hard  cn 1157  Search 1157

leetcode 53 Maximum Subarray Easy  cn 53  Search 53

leetcode 837 New 21 Game Medium  cn 837  Search 837

leetcode 1209 Remove All Adjacent Duplicates in String II Medium  cn 1209  Search 1209

leetcode 950 Reveal Cards In Increasing Order Medium  cn 950  Search 950

leetcode 1145 Binary Tree Coloring Game Medium  cn 1145  Search 1145

leetcode 460 LFU Cache Hard  cn 460  Search 460

leetcode 320 Generalized Abbreviation Medium  cn 320  Search 320

leetcode 855 Exam Room Medium  cn 855  Search 855

leetcode 208 Implement Trie (Prefix Tree) Medium  cn 208  Search 208

leetcode 209 Minimum Size Subarray Sum Medium  cn 209  Search 209

leetcode 298 Binary Tree Longest Consecutive Sequence Medium  cn 298  Search 298

leetcode 1136 Parallel Courses Hard  cn 1136  Search 1136

leetcode 158 Read N Characters Given Read4 II - Call multiple times Hard  cn 158  Search 158

leetcode 1168 Optimize Water Distribution in a Village Hard  cn 1168  Search 1168

leetcode 200 Number of Islands Medium  cn 200  Search 200

leetcode 394 Decode String Medium  cn 394  Search 394

leetcode 360 Sort Transformed Array Medium  cn 360  Search 360

leetcode 1062 Longest Repeating Substring Medium  cn 1062  Search 1062

leetcode 354 Russian Doll Envelopes Hard  cn 354  Search 354

leetcode 753 Cracking the Safe Hard  cn 753  Search 753

leetcode 604 Design Compressed String Iterator Easy  cn 604  Search 604

leetcode 981 Time Based Key-Value Store Medium  cn 981  Search 981

leetcode 1155 Number of Dice Rolls With Target Sum Medium  cn 1155  Search 1155

leetcode 817 Linked List Components Medium  cn 817  Search 817

leetcode 353 Design Snake Game Medium  cn 353  Search 353

leetcode 792 Number of Matching Subsequences Medium  cn 792  Search 792

leetcode 1277 Count Square Submatrices with All Ones Medium  cn 1277  Search 1277

leetcode 1056 Confusing Number Easy  cn 1056  Search 1056

leetcode 731 My Calendar II Medium  cn 731  Search 731

leetcode 560 Subarray Sum Equals K Medium  cn 560  Search 560

leetcode 340 Longest Substring with At Most K Distinct Characters Hard  cn 340  Search 340

leetcode 424 Longest Repeating Character Replacement Medium  cn 424  Search 424

leetcode 174 Dungeon Game Hard  cn 174  Search 174

leetcode 815 Bus Routes Hard  cn 815  Search 815

leetcode 720 Longest Word in Dictionary Easy  cn 720  Search 720

leetcode 23 Merge k Sorted Lists Hard  cn 23  Search 23

leetcode 895 Maximum Frequency Stack Hard  cn 895  Search 895

leetcode 1293 Shortest Path in a Grid with Obstacles Elimination Hard  cn 1293  Search 1293

leetcode 949 Largest Time for Given Digits Easy  cn 949  Search 949

leetcode 115 Distinct Subsequences Hard  cn 115  Search 115

leetcode 146 LRU Cache Medium  cn 146  Search 146

leetcode 723 Candy Crush Medium  cn 723  Search 723

leetcode 393 UTF-8 Validation Medium  cn 393  Search 393

leetcode 64 Minimum Path Sum Medium  cn 64  Search 64

leetcode 2 Add Two Numbers Medium  cn 2  Search 2

leetcode 721 Accounts Merge Medium  cn 721  Search 721

leetcode 1000 Minimum Cost to Merge Stones Hard  cn 1000  Search 1000

leetcode 1188 Design Bounded Blocking Queue Medium  cn 1188  Search 1188

leetcode 130 Surrounded Regions Medium  cn 130  Search 130

leetcode 198 House Robber Easy  cn 198  Search 198

leetcode 85 Maximal Rectangle Hard  cn 85  Search 85

leetcode 325 Maximum Size Subarray Sum Equals k Medium  cn 325  Search 325

leetcode 212 Word Search II Hard  cn 212  Search 212

leetcode 361 Bomb Enemy Medium  cn 361  Search 361

leetcode 705 Design HashSet Easy  cn 705  Search 705

leetcode 91 Decode Ways Medium  cn 91  Search 91

leetcode 852 Peak Index in a Mountain Array Easy  cn 852  Search 852

leetcode 351 Android Unlock Patterns Medium  cn 351  Search 351

leetcode 802 Find Eventual Safe States Medium  cn 802  Search 802

leetcode 1105 Filling Bookcase Shelves Medium  cn 1105  Search 1105

leetcode 346 Moving Average from Data Stream Easy  cn 346  Search 346

leetcode 845 Longest Mountain in Array Medium  cn 845  Search 845

leetcode 4 Median of Two Sorted Arrays Hard  cn 4  Search 4

leetcode 549 Binary Tree Longest Consecutive Sequence II Medium  cn 549  Search 549

leetcode 719 Find K-th Smallest Pair Distance Hard  cn 719  Search 719

leetcode 307 Range Sum Query - Mutable Medium  cn 307  Search 307

leetcode 17 Letter Combinations of a Phone Number Medium  cn 17  Search 17

leetcode 380 Insert Delete GetRandom O(1) Medium  cn 380  Search 380

leetcode 163 Missing Ranges Medium  cn 163  Search 163

leetcode 332 Reconstruct Itinerary Medium  cn 332  Search 332

leetcode 139 Word Break Medium  cn 139  Search 139

leetcode 34 Find First and Last Position of Element in Sorted Array Medium  cn 34  Search 34

leetcode 218 The Skyline Problem Hard  cn 218  Search 218

leetcode 662 Maximum Width of Binary Tree Medium  cn 662  Search 662

leetcode 134 Gas Station Medium  cn 134  Search 134

leetcode 43 Multiply Strings Medium  cn 43  Search 43

leetcode 239 Sliding Window Maximum Hard  cn 239  Search 239

leetcode 42 Trapping Rain Water Hard  cn 42  Search 42

leetcode 246 Strobogrammatic Number Easy  cn 246  Search 246

leetcode 692 Top K Frequent Words Medium  cn 692  Search 692

leetcode 286 Walls and Gates Medium  cn 286  Search 286

leetcode 31 Next Permutation Medium  cn 31  Search 31

leetcode 986 Interval List Intersections Medium  cn 986  Search 986

leetcode 140 Word Break II Hard  cn 140  Search 140

leetcode 99 Recover Binary Search Tree Hard  cn 99  Search 99

leetcode 33 Search in Rotated Sorted Array Medium  cn 33  Search 33

leetcode 3 Longest Substring Without Repeating Characters Medium  cn 3  Search 3

leetcode 210 Course Schedule II Medium  cn 210  Search 210

leetcode 228 Summary Ranges Medium  cn 228  Search 228

leetcode 708 Insert into a Sorted Circular Linked List Medium  cn 708  Search 708

leetcode 16 3Sum Closest Medium  cn 16  Search 16

leetcode 524 Longest Word in Dictionary through Deleting Medium  cn 524  Search 524

leetcode 45 Jump Game II Hard  cn 45  Search 45

leetcode 72 Edit Distance Hard  cn 72  Search 72

leetcode 15 3Sum Medium  cn 15  Search 15

leetcode 162 Find Peak Element Medium  cn 162  Search 162

leetcode 128 Longest Consecutive Sequence Hard  cn 128  Search 128

leetcode 137 Single Number II Medium  cn 137  Search 137

leetcode 10 Regular Expression Matching Hard  cn 10  Search 10

leetcode 205 Isomorphic Strings Easy  cn 205  Search 205

leetcode 96 Unique Binary Search Trees Medium  cn 96  Search 96

leetcode 1267 Count Servers that Communicate Medium  cn 1267  Search 1267

leetcode 392 Is Subsequence Easy  cn 392  Search 392

leetcode 253 Meeting Rooms II Medium  cn 253  Search 253

leetcode 166 Fraction to Recurring Decimal Medium  cn 166  Search 166

leetcode 438 Find All Anagrams in a String Medium  cn 438  Search 438

leetcode 247 Strobogrammatic Number II Medium  cn 247  Search 247

leetcode 337 House Robber III Medium  cn 337  Search 337

leetcode 567 Permutation in String Medium  cn 567  Search 567

leetcode 706 Design HashMap Easy  cn 706  Search 706

leetcode 490 The Maze Medium  cn 490  Search 490

leetcode 316 Remove Duplicate Letters Hard  cn 316  Search 316

leetcode 480 Sliding Window Median Hard  cn 480  Search 480

leetcode 202 Happy Number Easy  cn 202  Search 202

leetcode 551 Student Attendance Record I Easy  cn 551  Search 551

leetcode 284 Peeking Iterator Medium  cn 284  Search 284

leetcode 652 Find Duplicate Subtrees Medium  cn 652  Search 652

leetcode 173 Binary Search Tree Iterator Medium  cn 173  Search 173

leetcode 609 Find Duplicate File in System Medium  cn 609  Search 609

leetcode 931 Minimum Falling Path Sum Medium  cn 931  Search 931

leetcode 274 H-Index Medium  cn 274  Search 274

leetcode 5 Longest Palindromic Substring Medium  cn 5  Search 5

leetcode 773 Sliding Puzzle Hard  cn 773  Search 773

leetcode 821 Shortest Distance to a Character Easy  cn 821  Search 821

leetcode 328 Odd Even Linked List Medium  cn 328  Search 328

leetcode 1123 Lowest Common Ancestor of Deepest Leaves Medium  cn 1123  Search 1123

leetcode 150 Evaluate Reverse Polish Notation Medium  cn 150  Search 150

leetcode 97 Interleaving String Hard  cn 97  Search 97

leetcode 310 Minimum Height Trees Medium  cn 310  Search 310

leetcode 94 Binary Tree Inorder Traversal Medium  cn 94  Search 94

leetcode 215 Kth Largest Element in an Array Medium  cn 215  Search 215

leetcode 724 Find Pivot Index Easy  cn 724  Search 724

leetcode 282 Expression Add Operators Hard  cn 282  Search 282

leetcode 417 Pacific Atlantic Water Flow Medium  cn 417  Search 417

leetcode 373 Find K Pairs with Smallest Sums Medium  cn 373  Search 373

leetcode 849 Maximize Distance to Closest Person Easy  cn 849  Search 849

leetcode 1060 Missing Element in Sorted Array Medium  cn 1060  Search 1060

leetcode 498 Diagonal Traverse Medium  cn 498  Search 498

leetcode 30 Substring with Concatenation of All Words Hard  cn 30  Search 30

leetcode 124 Binary Tree Maximum Path Sum Hard  cn 124  Search 124

leetcode 1051 Height Checker Easy  cn 1051  Search 1051

leetcode 54 Spiral Matrix Medium  cn 54  Search 54

leetcode 127 Word Ladder Medium  cn 127  Search 127

leetcode 958 Check Completeness of a Binary Tree Medium  cn 958  Search 958

leetcode 46 Permutations Medium  cn 46  Search 46

leetcode 658 Find K Closest Elements Medium  cn 658  Search 658

leetcode 165 Compare Version Numbers Medium  cn 165  Search 165

leetcode 207 Course Schedule Medium  cn 207  Search 207

leetcode 55 Jump Game Medium  cn 55  Search 55

leetcode 636 Exclusive Time of Functions Medium  cn 636  Search 636

leetcode 63 Unique Paths II Medium  cn 63  Search 63

leetcode 309 Best Time to Buy and Sell Stock with Cooldown Medium  cn 309  Search 309

leetcode 236 Lowest Common Ancestor of a Binary Tree Medium  cn 236  Search 236

leetcode 36 Valid Sudoku Medium  cn 36  Search 36

leetcode 389 Find the Difference Easy  cn 389  Search 389

leetcode 322 Coin Change Medium  cn 322  Search 322

leetcode 168 Excel Sheet Column Title Easy  cn 168  Search 168

leetcode 149 Max Points on a Line Hard  cn 149  Search 149

leetcode 20 Valid Parentheses Easy  cn 20  Search 20

leetcode 41 First Missing Positive Hard  cn 41  Search 41

leetcode 1047 Remove All Adjacent Duplicates In String Easy  cn 1047  Search 1047

leetcode 297 Serialize and Deserialize Binary Tree Hard  cn 297  Search 297

leetcode 374 Guess Number Higher or Lower Easy  cn 374  Search 374

leetcode 443 String Compression Easy  cn 443  Search 443

leetcode 49 Group Anagrams Medium  cn 49  Search 49

leetcode 8 String to Integer (atoi) Medium  cn 8  Search 8

leetcode 349 Intersection of Two Arrays Easy  cn 349  Search 349

leetcode 269 Alien Dictionary Hard  cn 269  Search 269

leetcode 117 Populating Next Right Pointers in Each Node II Medium  cn 117  Search 117

leetcode 227 Basic Calculator II Medium  cn 227  Search 227

leetcode 77 Combinations Medium  cn 77  Search 77

leetcode 152 Maximum Product Subarray Medium  cn 152  Search 152

leetcode 785 Is Graph Bipartite? Medium  cn 785  Search 785

leetcode 238 Product of Array Except Self Medium  cn 238  Search 238

leetcode 21 Merge Two Sorted Lists Easy  cn 21  Search 21

leetcode 136 Single Number Easy  cn 136  Search 136

leetcode 67 Add Binary Easy  cn 67  Search 67

leetcode 283 Move Zeroes Easy  cn 283  Search 283

leetcode 665 Non-decreasing Array Easy  cn 665  Search 665

leetcode 79 Word Search Medium  cn 79  Search 79

leetcode 289 Game of Life Medium  cn 289  Search 289

leetcode 1143 Longest Common Subsequence Medium  cn 1143  Search 1143

leetcode 50 Pow(x, n) Medium  cn 50  Search 50

leetcode 226 Invert Binary Tree Easy  cn 226  Search 226

leetcode 273 Integer to English Words Hard  cn 273  Search 273

leetcode 219 Contains Duplicate II Easy  cn 219  Search 219

leetcode 169 Majority Element Easy  cn 169  Search 169

leetcode 18 4Sum Medium  cn 18  Search 18

leetcode 84 Largest Rectangle in Histogram Hard  cn 84  Search 84

leetcode 543 Diameter of Binary Tree Easy  cn 543  Search 543

leetcode 647 Palindromic Substrings Medium  cn 647  Search 647

leetcode 190 Reverse Bits Easy  cn 190  Search 190

leetcode 122 Best Time to Buy and Sell Stock II Easy  cn 122  Search 122

leetcode 22 Generate Parentheses Medium  cn 22  Search 22

leetcode 113 Path Sum II Medium  cn 113  Search 113

leetcode 121 Best Time to Buy and Sell Stock Easy  cn 121  Search 121

leetcode 40 Combination Sum II Medium  cn 40  Search 40

leetcode 203 Remove Linked List Elements Easy  cn 203  Search 203

leetcode 66 Plus One Easy  cn 66  Search 66

leetcode 145 Binary Tree Postorder Traversal Hard  cn 145  Search 145

leetcode 38 Count and Say Easy  cn 38  Search 38

leetcode 12 Integer to Roman Medium  cn 12  Search 12

leetcode 572 Subtree of Another Tree Easy  cn 572  Search 572

leetcode 118 Pascal's Triangle Easy  cn 118  Search 118

leetcode 105 Construct Binary Tree from Preorder and Inorder Traversal Medium  cn 105  Search 105

leetcode 14 Longest Common Prefix Easy  cn 14  Search 14

leetcode 977 Squares of a Sorted Array Easy  cn 977  Search 977

leetcode 11 Container With Most Water Medium  cn 11  Search 11

leetcode 153 Find Minimum in Rotated Sorted Array Medium  cn 153  Search 153

leetcode 7 Reverse Integer Easy  cn 7  Search 7

leetcode 300 Longest Increasing Subsequence Medium  cn 300  Search 300

leetcode 412 Fizz Buzz Easy  cn 412  Search 412

leetcode 104 Maximum Depth of Binary Tree Easy  cn 104  Search 104

leetcode 75 Sort Colors Medium  cn 75  Search 75

leetcode 237 Delete Node in a Linked List Easy  cn 237  Search 237

leetcode 9 Palindrome Number Easy  cn 9  Search 9

leetcode 167 Two Sum II - Input array is sorted Easy  cn 167  Search 167

leetcode 287 Find the Duplicate Number Medium  cn 287  Search 287

leetcode 78 Subsets Medium  cn 78  Search 78

leetcode 1281 Subtract the Product and Sum of Digits of an Integer Easy  cn 1281  Search 1281

leetcode 39 Combination Sum Medium  cn 39  Search 39

leetcode 35 Search Insert Position Easy  cn 35  Search 35

leetcode 242 Valid Anagram Easy  cn 242  Search 242

leetcode 88 Merge Sorted Array Easy  cn 88  Search 88

leetcode 28 Implement strStr() Easy  cn 28  Search 28

leetcode 344 Reverse String Easy  cn 344  Search 344

leetcode 98 Validate Binary Search Tree Medium  cn 98  Search 98

leetcode 206 Reverse Linked List Easy  cn 206  Search 206

leetcode facebook:  cn facebook:  Search facebook:

leetcode 953 Verifying an Alien Dictionary Easy  cn 953  Search 953

leetcode 301 Remove Invalid Parentheses Hard  cn 301  Search 301

leetcode 1249 Minimum Remove to Make Valid Parentheses Medium  cn 1249  Search 1249

leetcode 973 K Closest Points to Origin Medium  cn 973  Search 973

leetcode 560 Subarray Sum Equals K Medium  cn 560  Search 560

leetcode 680 Valid Palindrome II Easy  cn 680  Search 680

leetcode 238 Product of Array Except Self Medium  cn 238  Search 238

leetcode 124 Binary Tree Maximum Path Sum Hard  cn 124  Search 124

leetcode 67 Add Binary Easy  cn 67  Search 67

leetcode 273 Integer to English Words Hard  cn 273  Search 273

leetcode 297 Serialize and Deserialize Binary Tree Hard  cn 297  Search 297

leetcode 426 Convert Binary Search Tree to Sorted Doubly Linked List Medium  cn 426  Search 426

leetcode 282 Expression Add Operators Hard  cn 282  Search 282

leetcode 269 Alien Dictionary Hard  cn 269  Search 269

leetcode 523 Continuous Subarray Sum Medium  cn 523  Search 523

leetcode 438 Find All Anagrams in a String Medium  cn 438  Search 438

leetcode 199 Binary Tree Right Side View Medium  cn 199  Search 199

leetcode 415 Add Strings Easy  cn 415  Search 415

leetcode 125 Valid Palindrome Easy  cn 125  Search 125

leetcode 23 Merge k Sorted Lists Hard  cn 23  Search 23

leetcode 76 Minimum Window Substring Hard  cn 76  Search 76

leetcode 211 Add and Search Word - Data structure design Medium  cn 211  Search 211

leetcode 158 Read N Characters Given Read4 II - Call multiple times Hard  cn 158  Search 158

leetcode 139 Word Break Medium  cn 139  Search 139

leetcode 278 First Bad Version Easy  cn 278  Search 278

leetcode 621 Task Scheduler Medium  cn 621  Search 621

leetcode 543 Diameter of Binary Tree Easy  cn 543  Search 543

leetcode 340 Longest Substring with At Most K Distinct Characters Hard  cn 340  Search 340

leetcode 986 Interval List Intersections Medium  cn 986  Search 986

leetcode 636 Exclusive Time of Functions Medium  cn 636  Search 636

leetcode 173 Binary Search Tree Iterator Medium  cn 173  Search 173

leetcode 31 Next Permutation Medium  cn 31  Search 31

leetcode 349 Intersection of Two Arrays Easy  cn 349  Search 349

leetcode 215 Kth Largest Element in an Array Medium  cn 215  Search 215

leetcode 133 Clone Graph Medium  cn 133  Search 133

leetcode 785 Is Graph Bipartite? Medium  cn 785  Search 785

leetcode 56 Merge Intervals Medium  cn 56  Search 56

leetcode 721 Accounts Merge Medium  cn 721  Search 721

leetcode 98 Validate Binary Search Tree Medium  cn 98  Search 98

leetcode 65 Valid Number Hard  cn 65  Search 65

leetcode 398 Random Pick Index Medium  cn 398  Search 398

leetcode 767 Reorganize String Medium  cn 767  Search 767

leetcode 1060 Missing Element in Sorted Array Medium  cn 1060  Search 1060

leetcode 689 Maximum Sum of 3 Non-Overlapping Subarrays Hard  cn 689  Search 689

leetcode 987 Vertical Order Traversal of a Binary Tree Medium  cn 987  Search 987

leetcode 311 Sparse Matrix Multiplication Medium  cn 311  Search 311

leetcode 286 Walls and Gates Medium  cn 286  Search 286

leetcode 824 Goat Latin Easy  cn 824  Search 824

leetcode 33 Search in Rotated Sorted Array Medium  cn 33  Search 33

leetcode 140 Word Break II Hard  cn 140  Search 140

leetcode 34 Find First and Last Position of Element in Sorted Array Medium  cn 34  Search 34

leetcode 71 Simplify Path Medium  cn 71  Search 71

leetcode 1197 Minimum Knight Moves Medium  cn 1197  Search 1197

leetcode 528 Random Pick with Weight Medium  cn 528  Search 528

leetcode 29 Divide Two Integers Medium  cn 29  Search 29

leetcode 88 Merge Sorted Array Easy  cn 88  Search 88

leetcode 247 Strobogrammatic Number II Medium  cn 247  Search 247

leetcode 304 Range Sum Query 2D - Immutable Medium  cn 304  Search 304

leetcode 1004 Max Consecutive Ones III Medium  cn 1004  Search 1004

leetcode 708 Insert into a Sorted Circular Linked List Medium  cn 708  Search 708

leetcode 143 Reorder List Medium  cn 143  Search 143

leetcode 863 All Nodes Distance K in Binary Tree Medium  cn 863  Search 863

leetcode 314 Binary Tree Vertical Order Traversal Medium  cn 314  Search 314

leetcode 253 Meeting Rooms II Medium  cn 253  Search 253

leetcode 200 Number of Islands Medium  cn 200  Search 200

leetcode 236 Lowest Common Ancestor of a Binary Tree Medium  cn 236  Search 236

leetcode 246 Strobogrammatic Number Easy  cn 246  Search 246

leetcode 825 Friends Of Appropriate Ages Medium  cn 825  Search 825

leetcode 146 LRU Cache Medium  cn 146  Search 146

leetcode 43 Multiply Strings Medium  cn 43  Search 43

leetcode 896 Monotonic Array Easy  cn 896  Search 896

leetcode 270 Closest Binary Search Tree Value Easy  cn 270  Search 270

leetcode 1027 Longest Arithmetic Sequence Medium  cn 1027  Search 1027

leetcode 162 Find Peak Element Medium  cn 162  Search 162

leetcode 380 Insert Delete GetRandom O(1) Medium  cn 380  Search 380

leetcode 249 Group Shifted Strings Medium  cn 249  Search 249

leetcode 452 Minimum Number of Arrows to Burst Balloons Medium  cn 452  Search 452

leetcode 958 Check Completeness of a Binary Tree Medium  cn 958  Search 958

leetcode 938 Range Sum of BST Easy  cn 938  Search 938

leetcode 138 Copy List with Random Pointer Medium  cn 138  Search 138

leetcode 1216 Valid Palindrome III Hard  cn 1216  Search 1216

leetcode 498 Diagonal Traverse Medium  cn 498  Search 498

leetcode 670 Maximum Swap Medium  cn 670  Search 670

leetcode 32 Longest Valid Parentheses Hard  cn 32  Search 32

leetcode 865 Smallest Subtree with all the Deepest Nodes Medium  cn 865  Search 865

leetcode 480 Sliding Window Median Hard  cn 480  Search 480

leetcode 963 Minimum Area Rectangle II Medium  cn 963  Search 963

leetcode 921 Minimum Add to Make Parentheses Valid Medium  cn 921  Search 921

leetcode 50 Pow(x, n) Medium  cn 50  Search 50

leetcode 494 Target Sum Medium  cn 494  Search 494

leetcode 350 Intersection of Two Arrays II Easy  cn 350  Search 350

leetcode 227 Basic Calculator II Medium  cn 227  Search 227

leetcode 647 Palindromic Substrings Medium  cn 647  Search 647

leetcode 616 Add Bold Tag in String Medium  cn 616  Search 616

leetcode 257 Binary Tree Paths Easy  cn 257  Search 257

leetcode 347 Top K Frequent Elements Medium  cn 347  Search 347

leetcode 1269 Number of Ways to Stay in the Same Place After Some Steps Hard  cn 1269  Search 1269

leetcode 549 Binary Tree Longest Consecutive Sequence II Medium  cn 549  Search 549

leetcode 766 Toeplitz Matrix Easy  cn 766  Search 766

leetcode 42 Trapping Rain Water Hard  cn 42  Search 42

leetcode 15 3Sum Medium  cn 15  Search 15

leetcode 839 Similar String Groups Hard  cn 839  Search 839

leetcode 339 Nested List Weight Sum Easy  cn 339  Search 339

leetcode 490 The Maze Medium  cn 490  Search 490

leetcode 10 Regular Expression Matching Hard  cn 10  Search 10

leetcode 1094 Car Pooling Medium  cn 1094  Search 1094

leetcode 692 Top K Frequent Words Medium  cn 692  Search 692

leetcode 114 Flatten Binary Tree to Linked List Medium  cn 114  Search 114

leetcode 348 Design Tic-Tac-Toe Medium  cn 348  Search 348

leetcode 529 Minesweeper Medium  cn 529  Search 529

leetcode 568 Maximum Vacation Days Hard  cn 568  Search 568

leetcode 1123 Lowest Common Ancestor of Deepest Leaves Medium  cn 1123  Search 1123

leetcode 22 Generate Parentheses Medium  cn 22  Search 22

leetcode 463 Island Perimeter Easy  cn 463  Search 463

leetcode 126 Word Ladder II Hard  cn 126  Search 126

leetcode 416 Partition Equal Subset Sum Medium  cn 416  Search 416

leetcode 79 Word Search Medium  cn 79  Search 79

leetcode 1146 Snapshot Array Medium  cn 1146  Search 1146

leetcode 334 Increasing Triplet Subsequence Medium  cn 334  Search 334

leetcode 266 Palindrome Permutation Easy  cn 266  Search 266

leetcode 78 Subsets Medium  cn 78  Search 78

leetcode 91 Decode Ways Medium  cn 91  Search 91

leetcode 127 Word Ladder Medium  cn 127  Search 127

leetcode 678 Valid Parenthesis String Medium  cn 678  Search 678

leetcode 157 Read N Characters Given Read4 Easy  cn 157  Search 157

leetcode 75 Sort Colors Medium  cn 75  Search 75

leetcode 969 Pancake Sorting Medium  cn 969  Search 969

leetcode 109 Convert Sorted List to Binary Search Tree Medium  cn 109  Search 109

leetcode 1 Two Sum Easy  cn 1  Search 1

leetcode 336 Palindrome Pairs Hard  cn 336  Search 336

leetcode 428 Serialize and Deserialize N-ary Tree Hard  cn 428  Search 428

leetcode 394 Decode String Medium  cn 394  Search 394

leetcode 111 Minimum Depth of Binary Tree Easy  cn 111  Search 111

leetcode 239 Sliding Window Maximum Hard  cn 239  Search 239

leetcode 277 Find the Celebrity Medium  cn 277  Search 277

leetcode 240 Search a 2D Matrix II Medium  cn 240  Search 240

leetcode 3 Longest Substring Without Repeating Characters Medium  cn 3  Search 3

leetcode 788 Rotated Digits Easy  cn 788  Search 788

leetcode 319 Bulb Switcher Medium  cn 319  Search 319

leetcode 325 Maximum Size Subarray Sum Equals k Medium  cn 325  Search 325

leetcode 212 Word Search II Hard  cn 212  Search 212

leetcode 161 One Edit Distance Medium  cn 161  Search 161

leetcode 223 Rectangle Area Medium  cn 223  Search 223

leetcode 210 Course Schedule II Medium  cn 210  Search 210

leetcode 791 Custom Sort String Medium  cn 791  Search 791

leetcode 637 Average of Levels in Binary Tree Easy  cn 637  Search 637

leetcode 1245 Tree Diameter Medium  cn 1245  Search 1245

leetcode 540 Single Element in a Sorted Array Medium  cn 540  Search 540

leetcode 166 Fraction to Recurring Decimal Medium  cn 166  Search 166

leetcode 419 Battleships in a Board Medium  cn 419  Search 419

leetcode 778 Swim in Rising Water Hard  cn 778  Search 778

leetcode 567 Permutation in String Medium  cn 567  Search 567

leetcode 207 Course Schedule Medium  cn 207  Search 207

leetcode 129 Sum Root to Leaf Numbers Medium  cn 129  Search 129

leetcode 2 Add Two Numbers Medium  cn 2  Search 2

leetcode 417 Pacific Atlantic Water Flow Medium  cn 417  Search 417

leetcode 515 Find Largest Value in Each Tree Row Medium  cn 515  Search 515

leetcode 676 Implement Magic Dictionary Medium  cn 676  Search 676

leetcode 1213 Intersection of Three Sorted Arrays Easy  cn 1213  Search 1213

leetcode 378 Kth Smallest Element in a Sorted Matrix Medium  cn 378  Search 378

leetcode 352 Data Stream as Disjoint Intervals Hard  cn 352  Search 352

leetcode 312 Burst Balloons Hard  cn 312  Search 312

leetcode 977 Squares of a Sorted Array Easy  cn 977  Search 977

leetcode 489 Robot Room Cleaner Hard  cn 489  Search 489

leetcode 8 String to Integer (atoi) Medium  cn 8  Search 8

leetcode 20 Valid Parentheses Easy  cn 20  Search 20

leetcode 121 Best Time to Buy and Sell Stock Easy  cn 121  Search 121

leetcode 505 The Maze II Medium  cn 505  Search 505

leetcode 53 Maximum Subarray Easy  cn 53  Search 53

leetcode 855 Exam Room Medium  cn 855  Search 855

leetcode 298 Binary Tree Longest Consecutive Sequence Medium  cn 298  Search 298

leetcode 1008 Construct Binary Search Tree from Preorder Traversal Medium  cn 1008  Search 1008

leetcode 614 Second Degree Follower Medium  cn 614  Search 614

leetcode 5 Longest Palindromic Substring Medium  cn 5  Search 5

leetcode 388 Longest Absolute File Path Medium  cn 388  Search 388

leetcode 658 Find K Closest Elements Medium  cn 658  Search 658

leetcode 772 Basic Calculator III Hard  cn 772  Search 772

leetcode 442 Find All Duplicates in an Array Medium  cn 442  Search 442

leetcode 128 Longest Consecutive Sequence Hard  cn 128  Search 128

leetcode 305 Number of Islands II Hard  cn 305  Search 305

leetcode 230 Kth Smallest Element in a BST Medium  cn 230  Search 230

leetcode 679 24 Game Hard  cn 679  Search 679

leetcode 19 Remove Nth Node From End of List Medium  cn 19  Search 19

leetcode 674 Longest Continuous Increasing Subsequence Easy  cn 674  Search 674

leetcode 1091 Shortest Path in Binary Matrix Medium  cn 1091  Search 1091

leetcode 105 Construct Binary Tree from Preorder and Inorder Traversal Medium  cn 105  Search 105

leetcode 93 Restore IP Addresses Medium  cn 93  Search 93

leetcode 681 Next Closest Time Medium  cn 681  Search 681

leetcode 516 Longest Palindromic Subsequence Medium  cn 516  Search 516

leetcode 317 Shortest Distance from All Buildings Hard  cn 317  Search 317

leetcode 341 Flatten Nested List Iterator Medium  cn 341  Search 341

leetcode 224 Basic Calculator Hard  cn 224  Search 224

leetcode 242 Valid Anagram Easy  cn 242  Search 242

leetcode 283 Move Zeroes Easy  cn 283  Search 283

leetcode 74 Search a 2D Matrix Medium  cn 74  Search 74

leetcode 468 Validate IP Address Medium  cn 468  Search 468

leetcode 875 Koko Eating Bananas Medium  cn 875  Search 875

leetcode 329 Longest Increasing Path in a Matrix Hard  cn 329  Search 329

leetcode 983 Minimum Cost For Tickets Medium  cn 983  Search 983

leetcode 73 Set Matrix Zeroes Medium  cn 73  Search 73

leetcode 939 Minimum Area Rectangle Medium  cn 939  Search 939

leetcode 214 Shortest Palindrome Hard  cn 214  Search 214

leetcode 57 Insert Interval Hard  cn 57  Search 57

leetcode 21 Merge Two Sorted Lists Easy  cn 21  Search 21

leetcode 102 Binary Tree Level Order Traversal Medium  cn 102  Search 102

leetcode 364 Nested List Weight Sum II Medium  cn 364  Search 364

leetcode 1026 Maximum Difference Between Node and Ancestor Medium  cn 1026  Search 1026

leetcode 46 Permutations Medium  cn 46  Search 46

leetcode 844 Backspace String Compare Easy  cn 844  Search 844

leetcode 39 Combination Sum Medium  cn 39  Search 39

leetcode 323 Number of Connected Components in an Undirected Graph Medium  cn 323  Search 323

leetcode 295 Find Median from Data Stream Hard  cn 295  Search 295

leetcode 13 Roman to Integer Easy  cn 13  Search 13

leetcode 41 First Missing Positive Hard  cn 41  Search 41

leetcode 852 Peak Index in a Mountain Array Easy  cn 852  Search 852

leetcode 17 Letter Combinations of a Phone Number Medium  cn 17  Search 17

leetcode 159 Longest Substring with At Most Two Distinct Characters Medium  cn 159  Search 159

leetcode 153 Find Minimum in Rotated Sorted Array Medium  cn 153  Search 153

leetcode 395 Longest Substring with At Least K Repeating Characters Medium  cn 395  Search 395

leetcode 1219 Path with Maximum Gold Medium  cn 1219  Search 1219

leetcode 160 Intersection of Two Linked Lists Easy  cn 160  Search 160

leetcode 410 Split Array Largest Sum Hard  cn 410  Search 410

leetcode 24 Swap Nodes in Pairs Medium  cn 24  Search 24

leetcode 209 Minimum Size Subarray Sum Medium  cn 209  Search 209

leetcode 4 Median of Two Sorted Arrays Hard  cn 4  Search 4

leetcode 435 Non-overlapping Intervals Medium  cn 435  Search 435

leetcode 229 Majority Element II Medium  cn 229  Search 229

leetcode 137 Single Number II Medium  cn 137  Search 137

leetcode 37 Sudoku Solver Hard  cn 37  Search 37

leetcode 62 Unique Paths Medium  cn 62  Search 62

leetcode 116 Populating Next Right Pointers in Each Node Medium  cn 116  Search 116

leetcode 346 Moving Average from Data Stream Easy  cn 346  Search 346

leetcode 328 Odd Even Linked List Medium  cn 328  Search 328

leetcode 703 Kth Largest Element in a Stream Easy  cn 703  Search 703

leetcode 51 N-Queens Hard  cn 51  Search 51

leetcode 208 Implement Trie (Prefix Tree) Medium  cn 208  Search 208

leetcode 414 Third Maximum Number Easy  cn 414  Search 414

leetcode 1108 Defanging an IP Address Easy  cn 1108  Search 1108

leetcode 332 Reconstruct Itinerary Medium  cn 332  Search 332

leetcode 178 Rank Scores Medium  cn 178  Search 178

leetcode 44 Wildcard Matching Hard  cn 44  Search 44

leetcode 117 Populating Next Right Pointers in Each Node II Medium  cn 117  Search 117

leetcode 152 Maximum Product Subarray Medium  cn 152  Search 152

leetcode 724 Find Pivot Index Easy  cn 724  Search 724

leetcode 148 Sort List Medium  cn 148  Search 148

leetcode 445 Add Two Numbers II Medium  cn 445  Search 445

leetcode 695 Max Area of Island Medium  cn 695  Search 695

leetcode 48 Rotate Image Medium  cn 48  Search 48

leetcode 437 Path Sum III Easy  cn 437  Search 437

leetcode 387 First Unique Character in a String Easy  cn 387  Search 387

leetcode 63 Unique Paths II Medium  cn 63  Search 63

leetcode 221 Maximal Square Medium  cn 221  Search 221

leetcode 113 Path Sum II Medium  cn 113  Search 113

leetcode 26 Remove Duplicates from Sorted Array Easy  cn 26  Search 26

leetcode 40 Combination Sum II Medium  cn 40  Search 40

leetcode 28 Implement strStr() Easy  cn 28  Search 28

leetcode 49 Group Anagrams Medium  cn 49  Search 49

leetcode 112 Path Sum Easy  cn 112  Search 112

leetcode 16 3Sum Closest Medium  cn 16  Search 16

leetcode 136 Single Number Easy  cn 136  Search 136

leetcode 118 Pascal's Triangle Easy  cn 118  Search 118

leetcode 509 Fibonacci Number Easy  cn 509  Search 509

leetcode 11 Container With Most Water Medium  cn 11  Search 11

leetcode 7 Reverse Integer Easy  cn 7  Search 7

leetcode 344 Reverse String Easy  cn 344  Search 344

leetcode 300 Longest Increasing Subsequence Medium  cn 300  Search 300

leetcode 54 Spiral Matrix Medium  cn 54  Search 54

leetcode 108 Convert Sorted Array to Binary Search Tree Easy  cn 108  Search 108

leetcode 70 Climbing Stairs Easy  cn 70  Search 70

leetcode 104 Maximum Depth of Binary Tree Easy  cn 104  Search 104

leetcode 206 Reverse Linked List Easy  cn 206  Search 206

leetcode Amazon:  cn Amazon:  Search Amazon:

leetcode NA 1192 Critical Connections in a Network Hard  cn NA  Search NA

leetcode 200 Number of Islands Medium  cn 200  Search 200

leetcode NA 994 Rotting Oranges Easy  cn NA  Search NA

leetcode NA 138 Copy List with Random Pointer Medium  cn NA  Search NA

leetcode NA 937 Reorder Data in Log Files Easy  cn NA  Search NA

leetcode 572 Subtree of Another Tree Easy  cn 572  Search 572

leetcode NA 819 Most Common Word Easy  cn NA  Search NA

leetcode 5 Longest Palindromic Substring Medium  cn 5  Search 5

leetcode NA 240 Search a 2D Matrix II Medium  cn NA  Search NA

leetcode 1 Two Sum Easy  cn 1  Search 1

leetcode 21 Merge Two Sorted Lists Easy  cn 21  Search 21

leetcode 146 LRU Cache Medium  cn 146  Search 146

leetcode NA 472 Concatenated Words Hard  cn NA  Search NA

leetcode NA 973 K Closest Points to Origin Medium  cn NA  Search NA

leetcode NA 957 Prison Cells After N Days Medium  cn NA  Search NA

leetcode NA 1268 Search Suggestions System Medium  cn NA  Search NA

leetcode 295 Find Median from Data Stream Hard  cn 295  Search 295

leetcode NA 1167 Minimum Cost to Connect Sticks Medium  cn NA  Search NA

leetcode 692 Top K Frequent Words Medium  cn 692  Search 692

leetcode 42 Trapping Rain Water Hard  cn 42  Search 42

leetcode 642 Design Search Autocomplete System Hard  cn 642  Search 642

leetcode NA 1102 Path With Maximum Minimum Value Medium  cn NA  Search NA

leetcode 23 Merge k Sorted Lists Hard  cn 23  Search 23

leetcode NA 126 Word Ladder II Hard  cn NA  Search NA

leetcode 140 Word Break II Hard  cn 140  Search 140

leetcode 297 Serialize and Deserialize Binary Tree Hard  cn 297  Search 297

leetcode NA 866 Prime Palindrome Medium  cn NA  Search NA

leetcode 212 Word Search II Hard  cn 212  Search 212

leetcode 460 LFU Cache Hard  cn 460  Search 460

leetcode 127 Word Ladder Medium  cn 127  Search 127

leetcode 1000 Minimum Cost to Merge Stones Hard  cn 1000  Search 1000

leetcode NA 588 Design In-Memory File System Hard  cn NA  Search NA

leetcode NA 348 Design Tic-Tac-Toe Medium  cn NA  Search NA

leetcode NA 456 132 Pattern Medium  cn NA  Search NA

leetcode 253 Meeting Rooms II Medium  cn 253  Search 253

leetcode NA 694 Number of Distinct Islands Medium  cn NA  Search NA

leetcode 49 Group Anagrams Medium  cn 49  Search 49

leetcode 239 Sliding Window Maximum Hard  cn 239  Search 239

leetcode 273 Integer to English Words Hard  cn 273  Search 273

leetcode 20 Valid Parentheses Easy  cn 20  Search 20

leetcode NA 545 Boundary of Binary Tree Medium  cn NA  Search NA

leetcode NA 1152 Analyze User Website Visit Pattern Medium  cn NA  Search NA

leetcode NA 1044 Longest Duplicate Substring Hard  cn NA  Search NA

leetcode NA 347 Top K Frequent Elements Medium  cn NA  Search NA

leetcode NA 1099 Two Sum Less Than K Easy  cn NA  Search NA

leetcode 99 Recover Binary Search Tree Hard  cn 99  Search 99

leetcode 770 Basic Calculator IV Hard  cn 770  Search 770

leetcode 980 Unique Paths III Hard  cn 980  Search 980

leetcode 121 Best Time to Buy and Sell Stock Easy  cn 121  Search 121

leetcode NA 155 Min Stack Easy  cn NA  Search NA

leetcode 1155 Number of Dice Rolls With Target Sum Medium  cn 1155  Search 1155

leetcode 380 Insert Delete GetRandom O(1) Medium  cn 380  Search 380

leetcode NA 74 Search a 2D Matrix Medium  cn NA  Search NA

leetcode 981 Time Based Key-Value Store Medium  cn 981  Search 981

leetcode NA 103 Binary Tree Zigzag Level Order Traversal Medium  cn NA  Search NA

leetcode NA 675 Cut Off Trees for Golf Event Hard  cn NA  Search NA

leetcode 3 Longest Substring Without Repeating Characters Medium  cn 3  Search 3

leetcode 2 Add Two Numbers Medium  cn 2  Search 2

leetcode 139 Word Break Medium  cn 139  Search 139

leetcode 15 3Sum Medium  cn 15  Search 15

leetcode NA 759 Employee Free Time Hard  cn NA  Search NA

leetcode 33 Search in Rotated Sorted Array Medium  cn 33  Search 33

leetcode NA 733 Flood Fill Easy  cn NA  Search NA

leetcode NA 863 All Nodes Distance K in Binary Tree Medium  cn NA  Search NA

leetcode 238 Product of Array Except Self Medium  cn 238  Search 238

leetcode NA 1236 Web Crawler Medium  cn NA  Search NA

leetcode 772 Basic Calculator III Hard  cn 772  Search 772

leetcode 322 Coin Change Medium  cn 322  Search 322

leetcode 64 Minimum Path Sum Medium  cn 64  Search 64

leetcode NA 143 Reorder List Medium  cn NA  Search NA

leetcode 706 Design HashMap Easy  cn 706  Search 706

leetcode NA 535 Encode and Decode TinyURL Medium  cn NA  Search NA

leetcode 767 Reorganize String Medium  cn 767  Search 767

leetcode 53 Maximum Subarray Easy  cn 53  Search 53

leetcode 54 Spiral Matrix Medium  cn 54  Search 54

leetcode NA 739 Daily Temperatures Medium  cn NA  Search NA

leetcode 490 The Maze Medium  cn 490  Search 490

leetcode NA 622 Design Circular Queue Medium  cn NA  Search NA

leetcode NA 224 Basic Calculator Hard  cn NA  Search NA

leetcode NA 116 Populating Next Right Pointers in Each Node Medium  cn NA  Search NA

leetcode NA 449 Serialize and Deserialize BST Medium  cn NA  Search NA

leetcode NA 109 Convert Sorted List to Binary Search Tree Medium  cn NA  Search NA

leetcode NA 503 Next Greater Element II Medium  cn NA  Search NA

leetcode 12 Integer to Roman Medium  cn 12  Search 12

leetcode NA 133 Clone Graph Medium  cn NA  Search NA

leetcode NA 1172 Dinner Plate Stacks Hard  cn NA  Search NA

leetcode 206 Reverse Linked List Easy  cn 206  Search 206

leetcode 79 Word Search Medium  cn 79  Search 79

leetcode NA 909 Snakes and Ladders Medium  cn NA  Search NA

leetcode 289 Game of Life Medium  cn 289  Search 289

leetcode 45 Jump Game II Hard  cn 45  Search 45

leetcode NA 173 Binary Search Tree Iterator Medium  cn NA  Search NA

leetcode 17 Letter Combinations of a Phone Number Medium  cn 17  Search 17

leetcode 124 Binary Tree Maximum Path Sum Hard  cn 124  Search 124

leetcode NA 628 Maximum Product of Three Numbers Easy  cn NA  Search NA

leetcode 11 Container With Most Water Medium  cn 11  Search 11

leetcode NA 314 Binary Tree Vertical Order Traversal Medium  cn NA  Search NA

leetcode NA 556 Next Greater Element III Medium  cn NA  Search NA

leetcode NA 1038 Binary Search Tree to Greater Sum Tree Medium  cn NA  Search NA

leetcode NA 1100 Find K-Length Substrings With No Repeated Characters Medium  cn NA  Search NA

leetcode 236 Lowest Common Ancestor of a Binary Tree Medium  cn 236  Search 236

leetcode NA 1066 Campus Bikes II Medium  cn NA  Search NA

leetcode NA 496 Next Greater Element I Easy  cn NA  Search NA

leetcode NA 854 K-Similar Strings Hard  cn NA  Search NA

leetcode NA 978 Longest Turbulent Subarray Medium  cn NA  Search NA

leetcode 815 Bus Routes Hard  cn 815  Search 815

leetcode 1011 Capacity To Ship Packages Within D Days Medium  cn 1011  Search 1011

leetcode 269 Alien Dictionary Hard  cn 269  Search 269

leetcode 1031 Maximum Sum of Two Non-Overlapping Subarrays Medium  cn 1031  Search 1031

leetcode 91 Decode Ways Medium  cn 91  Search 91

leetcode NA 963 Minimum Area Rectangle II Medium  cn NA  Search NA

leetcode 97 Interleaving String Hard  cn 97  Search 97

leetcode NA 437 Path Sum III Easy  cn NA  Search NA

leetcode 210 Course Schedule II Medium  cn 210  Search 210

leetcode NA 881 Boats to Save People Medium  cn NA  Search NA

leetcode 98 Validate Binary Search Tree Medium  cn 98  Search 98

leetcode NA 547 Friend Circles Medium  cn NA  Search NA

leetcode NA 211 Add and Search Word - Data structure design Medium  cn NA  Search NA

leetcode NA 277 Find the Celebrity Medium  cn NA  Search NA

leetcode 207 Course Schedule Medium  cn 207  Search 207

leetcode NA 4 Median of Two Sorted Arrays Hard  cn NA  Search NA

leetcode 353 Design Snake Game Medium  cn 353  Search 353

leetcode 72 Edit Distance Hard  cn 72  Search 72

leetcode NA 1279 Traffic Light Controlled Intersection Easy  cn NA  Search NA

leetcode 939 Minimum Area Rectangle Medium  cn 939  Search 939

leetcode NA 1214 Two Sum BSTs Medium  cn NA  Search NA

leetcode NA 388 Longest Absolute File Path Medium  cn NA  Search NA

leetcode NA 0313 997 Find the Town Judge Easy  cn NA  Search NA

leetcode NA 409 Longest Palindrome Easy  cn NA  Search NA

leetcode NA 384 Shuffle an Array Medium  cn NA  Search NA

leetcode 208 Implement Trie (Prefix Tree) Medium  cn 208  Search 208

leetcode NA 640 Solve the Equation Medium  cn NA  Search NA

leetcode NA 387 First Unique Character in a String Easy  cn NA  Search NA

leetcode NA 192 Word Frequency Medium  cn NA  Search NA

leetcode 84 Largest Rectangle in Histogram Hard  cn 84  Search 84

leetcode NA 678 Valid Parenthesis String Medium  cn NA  Search NA

leetcode 105 Construct Binary Tree from Preorder and Inorder Traversal Medium  cn 105  Search 105

leetcode NA 93 Restore IP Addresses Medium  cn NA  Search NA

leetcode NA 445 Add Two Numbers II Medium  cn NA  Search NA

leetcode NA 1010 Pairs of Songs With Total Durations Divisible by 60 Easy  cn NA  Search NA

leetcode NA 323 Number of Connected Components in an Undirected Graph Medium  cn NA  Search NA

leetcode 215 Kth Largest Element in an Array Medium  cn 215  Search 215

leetcode NA 135 Candy Hard  cn NA  Search NA

leetcode 218 The Skyline Problem Hard  cn 218  Search 218

leetcode 560 Subarray Sum Equals K Medium  cn 560  Search 560

leetcode NA 690 Employee Importance Easy  cn NA  Search NA

leetcode 399 Evaluate Division Medium  cn 399  Search 399

leetcode NA 341 Flatten Nested List Iterator Medium  cn NA  Search NA

leetcode NA 966 Vowel Spellchecker Medium  cn NA  Search NA

leetcode NA 32 Longest Valid Parentheses Hard  cn NA  Search NA

leetcode 1032 Stream of Characters Hard  cn 1032  Search 1032

leetcode 336 Palindrome Pairs Hard  cn 336  Search 336

leetcode 287 Find the Duplicate Number Medium  cn 287  Search 287

leetcode NA 995 Minimum Number of K Consecutive Bit Flips Hard  cn NA  Search NA

leetcode NA 48 Rotate Image Medium  cn NA  Search NA

leetcode NA 187 Repeated DNA Sequences Medium  cn NA  Search NA

leetcode NA 102 Binary Tree Level Order Traversal Medium  cn NA  Search NA

leetcode NA 518 Coin Change 2 Medium  cn NA  Search NA

leetcode 63 Unique Paths II Medium  cn 63  Search 63

leetcode 227 Basic Calculator II Medium  cn 227  Search 227

leetcode 36 Valid Sudoku Medium  cn 36  Search 36

leetcode 307 Range Sum Query - Mutable Medium  cn 307  Search 307

leetcode 489 Robot Room Cleaner Hard  cn 489  Search 489

leetcode NA 794 Valid Tic-Tac-Toe State Medium  cn NA  Search NA

leetcode 41 First Missing Positive Hard  cn 41  Search 41

leetcode 1060 Missing Element in Sorted Array Medium  cn 1060  Search 1060

leetcode NA 992 Subarrays with K Different Integers Hard  cn NA  Search NA

leetcode NA 321 Create Maximum Number Hard  cn NA  Search NA

leetcode 1219 Path with Maximum Gold Medium  cn 1219  Search 1219

leetcode 153 Find Minimum in Rotated Sorted Array Medium  cn 153  Search 153

leetcode NA 270 Closest Binary Search Tree Value Easy  cn NA  Search NA

leetcode 300 Longest Increasing Subsequence Medium  cn 300  Search 300

leetcode 128 Longest Consecutive Sequence Hard  cn 128  Search 128

leetcode NA 987 Vertical Order Traversal of a Binary Tree Medium  cn NA  Search NA

leetcode NA 703 Kth Largest Element in a Stream Easy  cn NA  Search NA

leetcode 737 Sentence Similarity II Medium  cn 737  Search 737

leetcode NA 1091 Shortest Path in Binary Matrix Medium  cn NA  Search NA

leetcode 543 Diameter of Binary Tree Easy  cn 543  Search 543

leetcode NA 100 Same Tree Easy  cn NA  Search NA

leetcode 498 Diagonal Traverse Medium  cn 498  Search 498

leetcode 78 Subsets Medium  cn 78  Search 78

leetcode 1188 Design Bounded Blocking Queue Medium  cn 1188  Search 1188

leetcode NA 59 Spiral Matrix II Medium  cn NA  Search NA

leetcode 410 Split Array Largest Sum Hard  cn 410  Search 410

leetcode 317 Shortest Distance from All Buildings Hard  cn 317  Search 317

leetcode NA 234 Palindrome Linked List Easy  cn NA  Search NA

leetcode 50 Pow(x, n) Medium  cn 50  Search 50

leetcode 785 Is Graph Bipartite? Medium  cn 785  Search 785

leetcode 165 Compare Version Numbers Medium  cn 165  Search 165

leetcode 150 Evaluate Reverse Polish Notation Medium  cn 150  Search 150

leetcode NA 1024 Video Stitching Medium  cn NA  Search NA

leetcode 56 Merge Intervals Medium  cn 56  Search 56

leetcode NA 468 Validate IP Address Medium  cn NA  Search NA

leetcode 221 Maximal Square Medium  cn 221  Search 221

leetcode NA 106 Construct Binary Tree from Inorder and Postorder Traversal Medium  cn NA  Search NA

leetcode 315 Count of Smaller Numbers After Self Hard  cn 315  Search 315

leetcode NA 1229 Meeting Scheduler Medium  cn NA  Search NA

leetcode 284 Peeking Iterator Medium  cn 284  Search 284

leetcode NA 378 Kth Smallest Element in a Sorted Matrix Medium  cn NA  Search NA

leetcode NA 529 Minesweeper Medium  cn NA  Search NA

leetcode NA 57 Insert Interval Hard  cn NA  Search NA

leetcode NA 37 Sudoku Solver Hard  cn NA  Search NA

leetcode 22 Generate Parentheses Medium  cn 22  Search 22

leetcode NA 525 Contiguous Array Medium  cn NA  Search NA

leetcode 480 Sliding Window Median Hard  cn 480  Search 480

leetcode NA 1202 Smallest String With Swaps Medium  cn NA  Search NA

leetcode 632 Smallest Range Covering Elements from K Lists Hard  cn 632  Search 632

leetcode NA 702 Search in a Sorted Array of Unknown Size Medium  cn NA  Search NA

leetcode 721 Accounts Merge Medium  cn 721  Search 721

leetcode NA 1120 Maximum Average Subtree Medium  cn NA  Search NA

leetcode NA 516 Longest Palindromic Subsequence Medium  cn NA  Search NA

leetcode NA 419 Battleships in a Board Medium  cn NA  Search NA

leetcode NA 1104 Path In Zigzag Labelled Binary Tree Medium  cn NA  Search NA

leetcode 18 4Sum Medium  cn 18  Search 18

leetcode 55 Jump Game Medium  cn 55  Search 55

leetcode NA 542 01 Matrix Medium  cn NA  Search NA

leetcode NA 787 Cheapest Flights Within K Stops Medium  cn NA  Search NA

leetcode NA 101 Symmetric Tree Easy  cn NA  Search NA

leetcode 351 Android Unlock Patterns Medium  cn 351  Search 351

leetcode NA 653 Two Sum IV - Input is a BST Easy  cn NA  Search NA

leetcode NA 52 N-Queens II Hard  cn NA  Search NA

leetcode NA 463 Island Perimeter Easy  cn NA  Search NA

leetcode NA 123 Best Time to Buy and Sell Stock III Hard  cn NA  Search NA

leetcode 96 Unique Binary Search Trees Medium  cn 96  Search 96

leetcode 417 Pacific Atlantic Water Flow Medium  cn 417  Search 417

leetcode 340 Longest Substring with At Most K Distinct Characters Hard  cn 340  Search 340

leetcode NA 312 Burst Balloons Hard  cn NA  Search NA

leetcode 662 Maximum Width of Binary Tree Medium  cn 662  Search 662

leetcode 647 Palindromic Substrings Medium  cn 647  Search 647

leetcode NA 390 Elimination Game Medium  cn NA  Search NA

leetcode NA 44 Wildcard Matching Hard  cn NA  Search NA

leetcode NA 407 Trapping Rain Water II Hard  cn NA  Search NA

leetcode 88 Merge Sorted Array Easy  cn 88  Search 88

leetcode 394 Decode String Medium  cn 394  Search 394

leetcode 373 Find K Pairs with Smallest Sums Medium  cn 373  Search 373

leetcode 528 Random Pick with Weight Medium  cn 528  Search 528

leetcode NA 621 Task Scheduler Medium  cn NA  Search NA

leetcode NA 1275 Find Winner on a Tic Tac Toe Game Easy  cn NA  Search NA

leetcode 39 Combination Sum Medium  cn 39  Search 39

leetcode NA 368 Largest Divisible Subset Medium  cn NA  Search NA

leetcode NA 199 Binary Tree Right Side View Medium  cn NA  Search NA

leetcode NA 352 Data Stream as Disjoint Intervals Hard  cn NA  Search NA

leetcode NA 82 Remove Duplicates from Sorted List II Medium  cn NA  Search NA

leetcode NA 1161 Maximum Level Sum of a Binary Tree Medium  cn NA  Search NA

leetcode 46 RangeSumQuery2DImmutable Medium  cn 46  Search 46

leetcode NA 1002 Find Common Characters Easy  cn NA  Search NA

leetcode NA 836 Rectangle Overlap Easy  cn NA  Search NA

leetcode NA 735 Asteroid Collision Medium  cn NA  Search NA

leetcode NA 339 Nested List Weight Sum Easy  cn NA  Search NA

leetcode 31 Next Permutation Medium  cn 31  Search 31

leetcode NA 1130 Minimum Cost Tree From Leaf Values Medium  cn NA  Search NA

leetcode 117 Populating Next Right Pointers in Each Node II Medium  cn 117  Search 117

leetcode 242 Valid Anagram Easy  cn 242  Search 242

leetcode NA 698 Partition to K Equal Sum Subsets Medium  cn NA  Search NA

leetcode NA 695 Max Area of Island Medium  cn NA  Search NA

leetcode 75 Sort Colors Medium  cn 75  Search 75

leetcode NA 741 Cherry Pickup Hard  cn NA  Search NA

leetcode 286 Walls and Gates Medium  cn 286  Search 286

leetcode NA 272 Closest Binary Search Tree Value II Hard  cn NA  Search NA

leetcode 130 Surrounded Regions Medium  cn 130  Search 130

leetcode 708 Insert into a Sorted Circular Linked List Medium  cn 708  Search 708

leetcode 895 Maximum Frequency Stack Hard  cn 895  Search 895

leetcode 354 Russian Doll Envelopes Hard  cn 354  Search 354

leetcode 76 Minimum Window Substring Hard  cn 76  Search 76

leetcode 10 Regular Expression Matching Hard  cn 10  Search 10

leetcode NA 70 Climbing Stairs Easy  cn NA  Search NA

leetcode NA 969 Pancake Sorting Medium  cn NA  Search NA

leetcode 636 Exclusive Time of Functions Medium  cn 636  Search 636

leetcode 1143 Longest Common Subsequence Medium  cn 1143  Search 1143

leetcode NA 539 Minimum Time Difference Medium  cn NA  Search NA

leetcode NA 71 Simplify Path Medium  cn NA  Search NA

leetcode 228 Summary Ranges Medium  cn 228  Search 228

leetcode NA 974 Subarray Sums Divisible by K Medium  cn NA  Search NA

leetcode NA 1122 Relative Sort Array Easy  cn NA  Search NA

leetcode NA 154 Find Minimum in Rotated Sorted Array II Hard  cn NA  Search NA

leetcode 169 Majority Element Easy  cn 169  Search 169

leetcode NA 81 Search in Rotated Sorted Array II Medium  cn NA  Search NA

leetcode 85 Maximal Rectangle Hard  cn 85  Search 85

leetcode NA 6 ZigZag Conversion Medium  cn NA  Search NA

leetcode NA 19 Remove Nth Node From End of List Medium  cn NA  Search NA

leetcode 222 Count Complete Tree Nodes Medium  cn 222  Search 222

leetcode NA 25 Reverse Nodes in k-Group Hard  cn NA  Search NA

leetcode NA 132 Palindrome Partitioning II Hard  cn NA  Search NA

leetcode 62 Unique Paths Medium  cn 62  Search 62

leetcode 1007 Minimum Domino Rotations For Equal Row Medium  cn 1007  Search 1007

leetcode NA 179 Largest Number Medium  cn NA  Search NA

leetcode NA 1046 Last Stone Weight Easy  cn NA  Search NA

leetcode NA 13 Roman to Integer Easy  cn NA  Search NA

leetcode NA 509 Fibonacci Number Easy  cn NA  Search NA

leetcode NA 83 Remove Duplicates from Sorted List Easy  cn NA  Search NA

leetcode NA 426 Convert Binary Search Tree to Sorted Doubly Linked List Medium  cn NA  Search NA

leetcode 122 Best Time to Buy and Sell Stock II Easy  cn 122  Search 122

leetcode NA 257 Binary Tree Paths Easy  cn NA  Search NA

leetcode 362 Design Hit Counter Medium  cn 362  Search 362

leetcode NA 1094 Car Pooling Medium  cn NA  Search NA

leetcode 337 House Robber III Medium  cn 337  Search 337

leetcode NA 688 Knight Probability in Chessboard Medium  cn NA  Search NA

leetcode NA 252 Meeting Rooms Easy  cn NA  Search NA

leetcode 68 Text Justification Hard  cn 68  Search 68

leetcode 115 Distinct Subsequences Hard  cn 115  Search 115

leetcode NA 350 Intersection of Two Arrays II Easy  cn NA  Search NA

leetcode 977 Squares of a Sorted Array Easy  cn 977  Search 977

leetcode NA 160 Intersection of Two Linked Lists Easy  cn NA  Search NA

leetcode NA 112 Path Sum Easy  cn NA  Search NA

leetcode NA 73 Set Matrix Zeroes Medium  cn NA  Search NA

leetcode NA 114 Flatten Binary Tree to Linked List Medium  cn NA  Search NA

leetcode NA 47 Permutations II Medium  cn NA  Search NA

leetcode NA 345 Reverse Vowels of a String Easy  cn NA  Search NA

leetcode 652 Find Duplicate Subtrees Medium  cn 652  Search 652

leetcode NA 701 Insert into a Binary Search Tree Medium  cn NA  Search NA

leetcode NA 217 Contains Duplicate Easy  cn NA  Search NA

leetcode NA 141 Linked List Cycle Easy  cn NA  Search NA

leetcode 332 Reconstruct Itinerary Medium  cn 332  Search 332

leetcode NA 250 Count Univalue Subtrees Medium  cn NA  Search NA

leetcode 801 Minimum Swaps To Make Sequences Increasing Medium  cn 801  Search 801

leetcode NA 235 Lowest Common Ancestor of a Binary Search Tree Easy  cn NA  Search NA

leetcode 134 Gas Station Medium  cn 134  Search 134

leetcode 310 Minimum Height Trees Medium  cn 310  Search 310

leetcode NA 716 Max Stack Easy  cn NA  Search NA

leetcode NA 1019 Next Greater Node In Linked List Medium  cn NA  Search NA

leetcode 94 Binary Tree Inorder Traversal Medium  cn 94  Search 94

leetcode NA 1022 Sum of Root To Leaf Binary Numbers Easy  cn NA  Search NA

leetcode NA 110 Balanced Binary Tree Easy  cn NA  Search NA

leetcode 14 Longest Common Prefix Easy  cn 14  Search 14

leetcode NA 395 Longest Substring with At Least K Repeating Characters Medium  cn NA  Search NA

leetcode NA 538 Convert BST to Greater Tree Easy  cn NA  Search NA

leetcode NA 61 Rotate List Medium  cn NA  Search NA

leetcode NA 415 Add Strings Easy  cn NA  Search NA

leetcode 205 Isomorphic Strings Easy  cn 205  Search 205

leetcode 163 Missing Ranges Medium  cn 163  Search 163

leetcode NA 541 Reverse String II Easy  cn NA  Search NA

leetcode NA 261 Graph Valid Tree Medium  cn NA  Search NA

leetcode NA 442 Find All Duplicates in an Array Medium  cn NA  Search NA

leetcode NA 684 Redundant Connection Medium  cn NA  Search NA

leetcode NA 671 Second Minimum Node In a Binary Tree Easy  cn NA  Search NA

leetcode 852 Peak Index in a Mountain Array Easy  cn 852  Search 852

leetcode NA 92 Reverse Linked List II Medium  cn NA  Search NA

leetcode NA 90 Subsets II Medium  cn NA  Search NA

leetcode NA 403 Frog Jump Hard  cn NA  Search NA

leetcode 152 Maximum Product Subarray Medium  cn 152  Search 152

leetcode 1197 Minimum Knight Moves Medium  cn 1197  Search 1197

leetcode 849 Maximize Distance to Closest Person Easy  cn 849  Search 849

leetcode 349 Intersection of Two Arrays Easy  cn 349  Search 349

leetcode 113 Path Sum II Medium  cn 113  Search 113

leetcode 8 String to Integer (atoi) Medium  cn 8  Search 8

leetcode 202 Happy Number Easy  cn 202  Search 202

leetcode NA 24 Swap Nodes in Pairs Medium  cn NA  Search NA

leetcode 167 Two Sum II - Input array is sorted Easy  cn 167  Search 167

leetcode NA 1160 Find Words That Can Be Formed by Characters Easy  cn NA  Search NA

leetcode 392 Is Subsequence Easy  cn 392  Search 392

leetcode NA 268 Missing Number Easy  cn NA  Search NA

leetcode NA 69 Sqrt(x) Easy  cn NA  Search NA

leetcode 438 Find All Anagrams in a String Medium  cn 438  Search 438

leetcode NA 1004 Max Consecutive Ones III Medium  cn NA  Search NA

leetcode 40 Combination Sum II Medium  cn 40  Search 40

leetcode NA 189 Rotate Array Easy  cn NA  Search NA

leetcode NA 334 Increasing Triplet Subsequence Medium  cn NA  Search NA

leetcode NA 637 Average of Levels in Binary Tree Easy  cn NA  Search NA

leetcode NA 51 N-Queens Hard  cn NA  Search NA

leetcode NA 559 Maximum Depth of N-ary Tree Easy  cn NA  Search NA

leetcode NA 993 Cousins in Binary Tree Easy  cn NA  Search NA

leetcode 145 Binary Tree Postorder Traversal Hard  cn 145  Search 145

leetcode 16 3Sum Closest Medium  cn 16  Search 16

leetcode 149 Max Points on a Line Hard  cn 149  Search 149

leetcode 304 Range Sum Query 2D - Immutable Medium  cn 304  Search 304

leetcode 34 Find First and Last Position of Element in Sorted Array Medium  cn 34  Search 34

leetcode NA 451 Sort Characters By Frequency Medium  cn NA  Search NA

leetcode NA 204 Count Primes Easy  cn NA  Search NA

leetcode 567 Permutation in String Medium  cn 567  Search 567

leetcode 459 Repeated Substring Pattern Easy  cn 459  Search 459

leetcode 329 Longest Increasing Path in a Matrix Hard  cn 329  Search 329

leetcode 162 Find Peak Element Medium  cn 162  Search 162

leetcode NA 230 Kth Smallest Element in a BST Medium  cn NA  Search NA

leetcode NA 29 Divide Two Integers Medium  cn NA  Search NA

leetcode NA 28 Implement strStr() Easy  cn NA  Search NA

leetcode NA 301 Remove Invalid Parentheses Hard  cn NA  Search NA

leetcode 299 Bulls and Cows Easy  cn 299  Search 299

leetcode NA 120 Triangle Medium  cn NA  Search NA

leetcode NA 485 Max Consecutive Ones Easy  cn NA  Search NA

leetcode 430 Flatten a Multilevel Doubly Linked List Medium  cn 430  Search 430

leetcode NA 523 Continuous Subarray Sum Medium  cn NA  Search NA

leetcode 283 Move Zeroes Easy  cn 283  Search 283

leetcode NA 338 Counting Bits Medium  cn NA  Search NA

leetcode NA 905 Sort Array By Parity Easy  cn NA  Search NA

leetcode 67 Add Binary Easy  cn 67  Search 67

leetcode 226 Invert Binary Tree Easy  cn 226  Search 226

leetcode 136 Single Number Easy  cn 136  Search 136

leetcode NA 557 Reverse Words in a String III Easy  cn NA  Search NA

leetcode NA 1299 Replace Elements with Greatest Element on Right Side Easy  cn NA  Search NA

leetcode NA 232 Implement Queue using Stacks Easy  cn NA  Search NA

leetcode NA 1249 Minimum Remove to Make Valid Parentheses Medium  cn NA  Search NA

leetcode NA 876 Middle of the Linked List Easy  cn NA  Search NA

leetcode 104 Maximum Depth of Binary Tree Easy  cn 104  Search 104

leetcode NA 183 Customers Who Never Order Easy  cn NA  Search NA

leetcode 198 House Robber Easy  cn 198  Search 198

leetcode NA 107 Binary Tree Level Order Traversal II Easy  cn NA  Search NA

leetcode NA 151 Reverse Words in a String Medium  cn NA  Search NA

leetcode 43 Multiply Strings Medium  cn 43  Search 43

leetcode NA 938 Range Sum of BST Easy  cn NA  Search NA

leetcode NA 617 Merge Two Binary Trees Easy  cn NA  Search NA

leetcode 412 Fizz Buzz Easy  cn 412  Search 412

leetcode 344 Reverse String Easy  cn 344  Search 344

leetcode 237 Delete Node in a Linked List Easy  cn 237  Search 237

leetcode NA 1108 Defanging an IP Address Easy  cn NA  Search NA

leetcode NA 125 Valid Palindrome Easy  cn NA  Search NA

leetcode 7 Reverse Integer Easy  cn 7  Search 7

leetcode microsoft:  cn microsoft:  Search microsoft:

leetcode 1239 Maximum Length of a Concatenated String with Unique Characters Medium  cn 1239  Search 1239

leetcode 273 Integer to English Words Hard  cn 273  Search 273

leetcode 138 Copy List with Random Pointer Medium  cn 138  Search 138

leetcode 5 Longest Palindromic Substring Medium  cn 5  Search 5

leetcode 794 Valid Tic-Tac-Toe State Medium  cn 794  Search 794

leetcode 134 Gas Station Medium  cn 134  Search 134

leetcode 348 Design Tic-Tac-Toe Medium  cn 348  Search 348

leetcode 42 Trapping Rain Water Hard  cn 42  Search 42

leetcode 146 LRU Cache Medium  cn 146  Search 146

leetcode 200 Number of Islands Medium  cn 200  Search 200

leetcode 151 Reverse Words in a String Medium  cn 151  Search 151

leetcode 103 Binary Tree Zigzag Level Order Traversal Medium  cn 103  Search 103

leetcode 25 Reverse Nodes in k-Group Hard  cn 25  Search 25

leetcode 98 Validate Binary Search Tree Medium  cn 98  Search 98

leetcode 428 Serialize and Deserialize N-ary Tree Hard  cn 428  Search 428

leetcode 105 Construct Binary Tree from Preorder and Inorder Traversal Medium  cn 105  Search 105

leetcode 510 Inorder Successor in BST II Medium  cn 510  Search 510

leetcode 22 Generate Parentheses Medium  cn 22  Search 22

leetcode 443 String Compression Easy  cn 443  Search 443

leetcode 206 Reverse Linked List Easy  cn 206  Search 206

leetcode 1 Two Sum Easy  cn 1  Search 1

leetcode 297 Serialize and Deserialize Binary Tree Hard  cn 297  Search 297

leetcode 909 Snakes and Ladders Medium  cn 909  Search 909

leetcode 232 Implement Queue using Stacks Easy  cn 232  Search 232

leetcode 1185 Day of the Week Easy  cn 1185  Search 1185

leetcode 116 Populating Next Right Pointers in Each Node Medium  cn 116  Search 116

leetcode 8 String to Integer (atoi) Medium  cn 8  Search 8

leetcode 218 The Skyline Problem Hard  cn 218  Search 218

leetcode 127 Word Ladder Medium  cn 127  Search 127

leetcode 679 24 Game Hard  cn 679  Search 679

leetcode 54 Spiral Matrix Medium  cn 54  Search 54

leetcode 93 Restore IP Addresses Medium  cn 93  Search 93

leetcode 23 Merge k Sorted Lists Hard  cn 23  Search 23

leetcode 557 Reverse Words in a String III Easy  cn 557  Search 557

leetcode 470 Implement Rand10() Using Rand7() Medium  cn 470  Search 470

leetcode 44 Wildcard Matching Hard  cn 44  Search 44

leetcode 236 Lowest Common Ancestor of a Binary Tree Medium  cn 236  Search 236

leetcode 124 Binary Tree Maximum Path Sum Hard  cn 124  Search 124

leetcode 445 Add Two Numbers II Medium  cn 445  Search 445

leetcode 99 Recover Binary Search Tree Hard  cn 99  Search 99

leetcode 1044 Longest Duplicate Substring Hard  cn 1044  Search 1044

leetcode 212 Word Search II Hard  cn 212  Search 212

leetcode 33 Search in Rotated Sorted Array Medium  cn 33  Search 33

leetcode 340 Longest Substring with At Most K Distinct Characters Hard  cn 340  Search 340

leetcode 836 Rectangle Overlap Easy  cn 836  Search 836

leetcode 457 Circular Array Loop Medium  cn 457  Search 457

leetcode 56 Merge Intervals Medium  cn 56  Search 56

leetcode 21 Merge Two Sorted Lists Easy  cn 21  Search 21

leetcode 46 Permutations Medium  cn 46  Search 46

leetcode 121 Best Time to Buy and Sell Stock Easy  cn 121  Search 121

leetcode 225 Implement Stack using Queues Easy  cn 225  Search 225

leetcode 37 Sudoku Solver Hard  cn 37  Search 37

leetcode 722 Remove Comments Medium  cn 722  Search 722

leetcode 772 Basic Calculator III Hard  cn 772  Search 772

leetcode 135 Candy Hard  cn 135  Search 135

leetcode 535 Encode and Decode TinyURL Medium  cn 535  Search 535

leetcode 642 Design Search Autocomplete System Hard  cn 642  Search 642

leetcode 48 Rotate Image Medium  cn 48  Search 48

leetcode 2 Add Two Numbers Medium  cn 2  Search 2

leetcode 53 Maximum Subarray Easy  cn 53  Search 53

leetcode 688 Knight Probability in Chessboard Medium  cn 688  Search 688

leetcode 556 Next Greater Element III Medium  cn 556  Search 556

leetcode 204 Count Primes Easy  cn 204  Search 204

leetcode 540 Single Element in a Sorted Array Medium  cn 540  Search 540

leetcode 450 Delete Node in a BST Medium  cn 450  Search 450

leetcode 622 Design Circular Queue Medium  cn 622  Search 622

leetcode 10 Regular Expression Matching Hard  cn 10  Search 10

leetcode 449 Serialize and Deserialize BST Medium  cn 449  Search 449

leetcode 240 Search a 2D Matrix II Medium  cn 240  Search 240

leetcode 165 Compare Version Numbers Medium  cn 165  Search 165

leetcode 3 Longest Substring Without Repeating Characters Medium  cn 3  Search 3

leetcode 49 Group Anagrams Medium  cn 49  Search 49

leetcode 153 Find Minimum in Rotated Sorted Array Medium  cn 153  Search 153

leetcode 468 Validate IP Address Medium  cn 468  Search 468

leetcode 74 Search a 2D Matrix Medium  cn 74  Search 74

leetcode 173 Binary Search Tree Iterator Medium  cn 173  Search 173

leetcode 155 Min Stack Easy  cn 155  Search 155

leetcode 207 Course Schedule Medium  cn 207  Search 207

leetcode 148 Sort List Medium  cn 148  Search 148

leetcode 285 Inorder Successor in BST Medium  cn 285  Search 285

leetcode 140 Word Break II Hard  cn 140  Search 140

leetcode 189 Rotate Array Easy  cn 189  Search 189

leetcode 767 Reorganize String Medium  cn 767  Search 767

leetcode 4 Median of Two Sorted Arrays Hard  cn 4  Search 4

leetcode 143 Reorder List Medium  cn 143  Search 143

leetcode 168 Excel Sheet Column Title Easy  cn 168  Search 168

leetcode 322 Coin Change Medium  cn 322  Search 322

leetcode 863 All Nodes Distance K in Binary Tree Medium  cn 863  Search 863

leetcode 68 Text Justification Hard  cn 68  Search 68

leetcode 36 Valid Sudoku Medium  cn 36  Search 36

leetcode 419 Battleships in a Board Medium  cn 419  Search 419

leetcode 545 Boundary of Binary Tree Medium  cn 545  Search 545

leetcode 269 Alien Dictionary Hard  cn 269  Search 269

leetcode 636 Exclusive Time of Functions Medium  cn 636  Search 636

leetcode 17 Letter Combinations of a Phone Number Medium  cn 17  Search 17

leetcode 238 Product of Array Except Self Medium  cn 238  Search 238

leetcode 460 LFU Cache Hard  cn 460  Search 460

leetcode 102 Binary Tree Level Order Traversal Medium  cn 102  Search 102

leetcode 387 First Unique Character in a String Easy  cn 387  Search 387

leetcode 117 Populating Next Right Pointers in Each Node II Medium  cn 117  Search 117

leetcode 1145 Binary Tree Coloring Game Medium  cn 1145  Search 1145

leetcode 32 Longest Valid Parentheses Hard  cn 32  Search 32

leetcode 239 Sliding Window Maximum Hard  cn 239  Search 239

leetcode 727 Minimum Window Subsequence Hard  cn 727  Search 727

leetcode 543 Diameter of Binary Tree Easy  cn 543  Search 543

leetcode 76 Minimum Window Substring Hard  cn 76  Search 76

leetcode 20 Valid Parentheses Easy  cn 20  Search 20

leetcode 73 Set Matrix Zeroes Medium  cn 73  Search 73

leetcode 75 Sort Colors Medium  cn 75  Search 75

leetcode 277 Find the Celebrity Medium  cn 277  Search 277

leetcode 528 Random Pick with Weight Medium  cn 528  Search 528

leetcode 15 3Sum Medium  cn 15  Search 15

leetcode 125 Valid Palindrome Easy  cn 125  Search 125

leetcode 1004 Max Consecutive Ones III Medium  cn 1004  Search 1004

leetcode 680 Valid Palindrome II Easy  cn 680  Search 680

leetcode 572 Subtree of Another Tree Easy  cn 572  Search 572

leetcode 347 Top K Frequent Elements Medium  cn 347  Search 347

leetcode 295 Find Median from Data Stream Hard  cn 295  Search 295

leetcode 92 Reverse Linked List II Medium  cn 92  Search 92

leetcode 41 First Missing Positive Hard  cn 41  Search 41

leetcode 253 Meeting Rooms II Medium  cn 253  Search 253

leetcode 24 Swap Nodes in Pairs Medium  cn 24  Search 24

leetcode 128 Longest Consecutive Sequence Hard  cn 128  Search 128

leetcode 224 Basic Calculator Hard  cn 224  Search 224

leetcode 969 Pancake Sorting Medium  cn 969  Search 969

leetcode 509 Fibonacci Number Easy  cn 509  Search 509

leetcode 695 Max Area of Island Medium  cn 695  Search 695

leetcode 186 Reverse Words in a String II Medium  cn 186  Search 186

leetcode 381 Insert Delete GetRandom O(1) - Duplicates allowed Hard  cn 381  Search 381

leetcode 567 Permutation in String Medium  cn 567  Search 567

leetcode 317 Shortest Distance from All Buildings Hard  cn 317  Search 317

leetcode 13 Roman to Integer Easy  cn 13  Search 13

leetcode 703 Kth Largest Element in a Stream Easy  cn 703  Search 703

leetcode 179 Largest Number Medium  cn 179  Search 179

leetcode 426 Convert Binary Search Tree to Sorted Doubly Linked List Medium  cn 426  Search 426

leetcode 490 The Maze Medium  cn 490  Search 490

leetcode 45 Jump Game II Hard  cn 45  Search 45

leetcode 126 Word Ladder II Hard  cn 126  Search 126

leetcode 234 Palindrome Linked List Easy  cn 234  Search 234

leetcode 706 Design HashMap Easy  cn 706  Search 706

leetcode 79 Word Search Medium  cn 79  Search 79

leetcode 438 Find All Anagrams in a String Medium  cn 438  Search 438

leetcode 717 1-bit and 2-bit Characters Easy  cn 717  Search 717

leetcode 328 Odd Even Linked List Medium  cn 328  Search 328

leetcode 284 Peeking Iterator Medium  cn 284  Search 284

leetcode 199 Binary Tree Right Side View Medium  cn 199  Search 199

leetcode 268 Missing Number Easy  cn 268  Search 268

leetcode 266 Palindrome Permutation Easy  cn 266  Search 266

leetcode 88 Merge Sorted Array Easy  cn 88  Search 88

leetcode 243 Shortest Word Distance Easy  cn 243  Search 243

leetcode 472 Concatenated Words Hard  cn 472  Search 472

leetcode 142 Linked List Cycle II Medium  cn 142  Search 142

leetcode 729 My Calendar I Medium  cn 729  Search 729

leetcode 1143 Longest Common Subsequence Medium  cn 1143  Search 1143

leetcode 110 Balanced Binary Tree Easy  cn 110  Search 110

leetcode 332 Reconstruct Itinerary Medium  cn 332  Search 332

leetcode 158 Read N Characters Given Read4 II - Call multiple times Hard  cn 158  Search 158

leetcode 287 Find the Duplicate Number Medium  cn 287  Search 287

leetcode 412 Fizz Buzz Easy  cn 412  Search 412

leetcode 311 Sparse Matrix Multiplication Medium  cn 311  Search 311

leetcode 383 Ransom Note Easy  cn 383  Search 383

leetcode 662 Maximum Width of Binary Tree Medium  cn 662  Search 662

leetcode 104 Maximum Depth of Binary Tree Easy  cn 104  Search 104

leetcode 406 Queue Reconstruction by Height Medium  cn 406  Search 406

leetcode 403 Frog Jump Hard  cn 403  Search 403

leetcode 402 Remove K Digits Medium  cn 402  Search 402

leetcode 228 Summary Ranges Medium  cn 228  Search 228

leetcode 84 Largest Rectangle in Histogram Hard  cn 84  Search 84

leetcode 314 Binary Tree Vertical Order Traversal Medium  cn 314  Search 314

leetcode 40 Combination Sum II Medium  cn 40  Search 40

leetcode 149 Max Points on a Line Hard  cn 149  Search 149

leetcode 721 Accounts Merge Medium  cn 721  Search 721

leetcode 235 Lowest Common Ancestor of a Binary Search Tree Easy  cn 235  Search 235

leetcode 63 Unique Paths II Medium  cn 63  Search 63

leetcode 62 Unique Paths Medium  cn 62  Search 62

leetcode 669 Trim a Binary Search Tree Easy  cn 669  Search 669

leetcode 69 Sqrt(x) Easy  cn 69  Search 69

leetcode 139 Word Break Medium  cn 139  Search 139

leetcode 515 Find Largest Value in Each Tree Row Medium  cn 515  Search 515

leetcode 210 Course Schedule II Medium  cn 210  Search 210

leetcode 252 Meeting Rooms Easy  cn 252  Search 252

leetcode 518 Coin Change 2 Medium  cn 518  Search 518

leetcode 346 Moving Average from Data Stream Easy  cn 346  Search 346

leetcode 85 Maximal Rectangle Hard  cn 85  Search 85

leetcode 987 Vertical Order Traversal of a Binary Tree Medium  cn 987  Search 987

leetcode 981 Time Based Key-Value Store Medium  cn 981  Search 981

leetcode 653 Two Sum IV - Input is a BST Easy  cn 653  Search 653

leetcode 28 Implement strStr() Easy  cn 28  Search 28

leetcode 286 Walls and Gates Medium  cn 286  Search 286

leetcode 362 Design Hit Counter Medium  cn 362  Search 362

leetcode 785 Is Graph Bipartite? Medium  cn 785  Search 785

leetcode 129 Sum Root to Leaf Numbers Medium  cn 129  Search 129

leetcode 378 Kth Smallest Element in a Sorted Matrix Medium  cn 378  Search 378

leetcode 430 Flatten a Multilevel Doubly Linked List Medium  cn 430  Search 430

leetcode 101 Symmetric Tree Easy  cn 101  Search 101

leetcode 152 Maximum Product Subarray Medium  cn 152  Search 152

leetcode 94 Binary Tree Inorder Traversal Medium  cn 94  Search 94

leetcode 77 Combinations Medium  cn 77  Search 77

leetcode 315 Count of Smaller Numbers After Self Hard  cn 315  Search 315

leetcode 442 Find All Duplicates in an Array Medium  cn 442  Search 442

leetcode 227 Basic Calculator II Medium  cn 227  Search 227

leetcode 160 Intersection of Two Linked Lists Easy  cn 160  Search 160

leetcode 219 Contains Duplicate II Easy  cn 219  Search 219

leetcode 70 Climbing Stairs Easy  cn 70  Search 70

leetcode 108 Convert Sorted Array to Binary Search Tree Easy  cn 108  Search 108

leetcode 344 Reverse String Easy  cn 344  Search 344

leetcode 39 Combination Sum Medium  cn 39  Search 39

leetcode 1192 Critical Connections in a Network Hard  cn 1192  Search 1192

leetcode 61 Rotate List Medium  cn 61  Search 61

leetcode 560 Subarray Sum Equals K Medium  cn 560  Search 560

leetcode 113 Path Sum II Medium  cn 113  Search 113

leetcode 279 Perfect Squares Medium  cn 279  Search 279

leetcode 100 Same Tree Easy  cn 100  Search 100

leetcode 215 Kth Largest Element in an Array Medium  cn 215  Search 215

leetcode 380 Insert Delete GetRandom O(1) Medium  cn 380  Search 380

leetcode 26 Remove Duplicates from Sorted Array Easy  cn 26  Search 26

leetcode 739 Daily Temperatures Medium  cn 739  Search 739

leetcode 394 Decode String Medium  cn 394  Search 394

leetcode 43 Multiply Strings Medium  cn 43  Search 43

leetcode 114 Flatten Binary Tree to Linked List Medium  cn 114  Search 114

leetcode 133 Clone Graph Medium  cn 133  Search 133

leetcode 19 Remove Nth Node From End of List Medium  cn 19  Search 19

leetcode 415 Add Strings Easy  cn 415  Search 415

leetcode 14 Longest Common Prefix Easy  cn 14  Search 14

leetcode 83 Remove Duplicates from Sorted List Easy  cn 83  Search 83

leetcode 64 Minimum Path Sum Medium  cn 64  Search 64

leetcode 91 Decode Ways Medium  cn 91  Search 91

leetcode 300 Longest Increasing Subsequence Medium  cn 300  Search 300

leetcode 973 K Closest Points to Origin Medium  cn 973  Search 973

leetcode 78 Subsets Medium  cn 78  Search 78

leetcode 50 Pow(x, n) Medium  cn 50  Search 50

leetcode 242 Valid Anagram Easy  cn 242  Search 242

leetcode 217 Contains Duplicate Easy  cn 217  Search 217

leetcode 198 House Robber Easy  cn 198  Search 198

leetcode 141 Linked List Cycle Easy  cn 141  Search 141

leetcode 34 Find First and Last Position of Element in Sorted Array Medium  cn 34  Search 34

leetcode 11 Container With Most Water Medium  cn 11  Search 11

leetcode 7 Reverse Integer Easy  cn 7  Search 7