| 1882 |
Process Tasks Using Servers |
Medium |
| 829 |
Consecutive Numbers Sum |
Medium |
| 726 |
Number of Atoms |
Hard |
| 720 |
Longest Word in Dictionary |
Easy |
| 395 |
Longest Substring with At Least K Repeating Characters |
Medium |
| 351 |
Android Unlock Patterns |
Medium |
| 533 |
Lonely Pixel II |
Medium |
| 531 |
Lonely Pixel I |
Medium |
| 354 |
Russian Doll Envelopes |
Hard |
| 663 |
Equal Tree Partition |
Medium |
| 661 |
Image Smoother |
Easy |
| 657 |
Judge Route Circle |
Easy |
| 654 |
Maximum Binary Tree |
Medium |
| 653 |
Two Sum IV - Input is a BST |
Easy |
| 650 |
2 Keys Keyboard |
Medium |
| 648 |
Replace Words |
Medium |
| 645 |
Set Mismatch |
Easy |
| 643 |
Maximum Average Subarray I |
Easy |
| 637 |
Average of Levels in Binary Tree |
Easy |
| 633 |
Sum of Square Numbers |
Easy |
| 628 |
Maximum Product of Three Numbers |
Easy |
| 627 |
Swap Salary |
Easy |
| 625 |
Minimum Factorization |
Medium |
| 624 |
Maximum Distance in Arrays |
Easy |
| 620 |
Not Boring Movies |
Easy |
| 619 |
Biggest Single Number |
Easy |
| 617 |
Merge Two Binary Trees |
Easy |
| 616 |
Add Bold Tag in String |
Medium |
| 613 |
Shortest Distance in a Line |
Easy |
| 610 |
Triangle Judgement |
Easy |
| 607 |
Sales Person |
Easy |
| 606 |
Construct String from Binary Tree |
Easy |
| 605 |
Can Place Flowers |
Easy |
| 604 |
Design Compressed String Iterator |
Easy |
| 603 |
Consecutive Available Seats |
Easy |
| 601 |
Human Traffic of Stadium |
hard |
| 599 |
Minimum Index Sum of Two Lists |
Easy |
| 598 |
Range Addition II |
Easy |
| 597 |
Friend Requests I: Overall Acceptance Rate |
Easy |
| 596 |
Classes More Than 5 Students |
Easy |
| 595 |
Big Countries |
Easy |
| 594 |
Longest Harmonious Subsequence |
Easy |
| 586 |
Customer Placing the Largest Number of Orders |
Easy |
| 584 |
Find Customer Referee |
Easy |
| 583 |
Delete Operation for Two Strings |
Medium |
| 581 |
Shortest Unsorted Continuous Subarray |
Easy |
| 580 |
Count Student Number in Departments |
Medium |
| 577 |
Employee Bonus |
Easy |
| 575 |
Distribute Candies |
Easy |
| 572 |
Subtree of Another Tree |
Easy |
| 570 |
Managers with at Least 5 Direct Reports |
Medium |
| 566 |
Reshape the Matrix |
Easy |
| 563 |
Binary Tree Tilt |
Easy |
| 562 |
Longest Line of Consecutive One in Matrix |
Medium |
| 561 |
Array Partition I |
Easy |
| 560 |
Subarray Sum Equals K |
Medium |
| 551 |
Student Attendance Record I |
Easy |
| 548 |
Split Array with Equal Sum |
Medium |
| 543 |
Diameter of Binary Tree |
Easy |
| 539 |
Minimum Time Difference |
Medium |
| 538 |
Convert BST to Greater Tree |
Easy |
| 537 |
Complex Number Multiplication |
Medium |
| 535 |
Encode and Decode TinyURL |
Medium |
| 532 |
K-diff Pairs in an Array |
Easy |
| 530 |
Minimum Absolute Difference in BST |
Easy |
| 526 |
Beautiful Arrangement |
Medium |
| 525 |
Contiguous Array |
Medium |
| 524 |
Longest Word in Dictionary through Deleting |
Medium |
| 521 |
Longest Uncommon Subsequence I |
Easy |
| 515 |
Find Largest Value in Each Tree Row |
Medium |
| 507 |
Perfect Number |
Easy |
| 506 |
Relative Ranks |
Easy |
| 503 |
Next Greater Element II |
Medium |
| 501 |
Find Mode in Binary Search Tree |
Easy |
| 500 |
Keyboard Row |
Easy |
| 496 |
Next Greater Element I |
Easy |
| 492 |
Construct the Rectangle |
Easy |
| 486 |
Predict the Winner |
Medium |
| 479 |
Largest Palindrome Product |
Easy |
| 477 |
Total Hamming Distance |
Medium |
| 468 |
Validate IP Address |
Medium |
| 463 |
Island Perimeter |
Easy |
| 459 |
Repeated Substring Pattern |
Easy |
| 458 |
Poor Pigs |
Easy |
| 455 |
Assign Cookies |
Easy |
| 454 |
4Sum II |
Medium |
| 453 |
Minimum Moves to Equal Array Elements |
Easy |
| 448 |
Find All Numbers Disappeared in an Array |
Easy |
| 447 |
Number of Boomerangs |
Easy |
| 442 |
Find All Duplicates in an Array |
Medium |
| 441 |
Arranging Coins |
Easy |
| 438 |
Find All Anagrams in a String |
Easy |
| 437 |
Path Sum III |
Easy |
| 435 |
Non-overlapping Intervals |
Medium |
| 434 |
Number of Segments in a String |
Easy |
| 422 |
Valid Word Square |
Easy |
| 415 |
Add Strings |
Easy |
| 414 |
Third Maximum Number |
Easy |
| 413 |
Arithmetic Slices |
Medium |
| 412 |
Fizz Buzz |
Easy |
| 409 |
Longest Palindrome |
Easy |
| 408 |
Valid Word Abbreviation |
Easy |
| 405 |
Convert a Number to Hexadecimal |
Easy |
| 404 |
Sum of Left Leaves |
Easy |
| 402 |
Remove K Digits |
Medium |
| 401 |
Binary Watch |
Easy |
| 392 |
Is Subsequence |
Medium |
| 389 |
Find the Difference |
Easy |
| 557 |
Reverse Words in a String III |
Easy |
| 542 |
01 Matrix |
Medium |
| 541 |
Reverse String II |
Easy |
| 520 |
Detect Capital |
Easy |
| 504 |
Base 7 |
Easy |
| 485 |
Max Consecutive Ones |
Easy |
| 476 |
Number Complement |
Easy |
| 461 |
Hamming Distance |
Easy |
| 394 |
Decode String |
Medium |
| 387 |
First Unique Character in a String |
Easy |
| 383 |
Ransom Note |
Easy |
| 374 |
Guess Number Higher or Lower |
Easy |
| 371 |
Sum of Two Integers |
Easy |
| 369 |
Plus One Linked List |
Medium |
| 367 |
Valid Perfect Square |
Easy |
| 362 |
Design Hit Counter |
Medium |
| 359 |
Logger Rate Limiter |
Easy |
| 350 |
Intersection of Two Arrays II |
Easy |
| 349 |
Intersection of Two Arrays |
Easy |
| 347 |
Top K Frequent Elements |
Medium |
| 346 |
Moving Average from Data Stream |
Easy |
| 345 |
Reverse Vowels of a String |
Easy |
| 344 |
Reverse String |
Easy |
| 343 |
Integer Break |
Medium |
| 342 |
Power of Four |
Easy |
| 341 |
Flatten Nested List Iterator |
Medium |
| 340 |
Longest Substring with At Most K Distinct Characters |
Hard |
| 339 |
Nested List Weight Sum |
Easy |
| 338 |
Counting Bits |
Medium |
| 336 |
Palindrome Pairs |
Hard |
| 332 |
Reconstruct Itinerary |
Medium |
| 331 |
Verify Preorder Serialization of a Binary Tree |
Medium |
| 330 |
Patching Array |
Hard |
| 328 |
Odd Even Linked List |
Medium |
| 326 |
Power of Three |
Easy |
| 325 |
Maximum Size Subarray Sum Equals k |
Medium |
| 319 |
Bulb Switcher |
Medium |
| 316 |
Remove Duplicate Letters |
Hard |
| 313 |
Super Ugly Number |
Medium |
| 311 |
Sparse Matrix Multiplication |
Medium |
| 306 |
Additive Number |
Medium |
| 304 |
Range Sum Query 2D - Immutable |
Medium |
| 303 |
Range Sum Query - Immutable |
Easy |
| 299 |
Bulls and Cows |
Medium |
| 298 |
Binary Tree Longest Consecutive Sequence |
Medium |
| 293 |
Flip Game |
Easy |
| 292 |
Nim Game |
Easy |
| 290 |
Word Pattern |
Easy |
| 288 |
Unique Word Abbreviation |
Medium |
| 287 |
Find the Duplicate Number |
Medium |
| 283 |
Move Zeroes |
Easy |
| 281 |
Zigzag Iterator |
Medium |
| 280 |
Wiggle Sort |
Medium |
| 278 |
First Bad Version |
Easy |
| 276 |
Paint Fence |
Easy |
| 273 |
Integer to English Words |
Hard |
| 272 |
Closest Binary Search Tree Value II |
Hard |
| 271 |
Encode and Decode Strings |
Medium |
| 270 |
Closest Binary Search Tree Value |
Easy |
| 269 |
Alien Dictionary |
Hard |
| 268 |
Missing Number |
Easy |
| 267 |
Palindrome Permutation II |
Medium |
| 266 |
Palindrome Permutation |
Easy |
| 265 |
Paint House II |
Hard |
| 264 |
Ugly Number II |
Medium |
| 263 |
Ugly Number |
Easy |
| 261 |
Graph Valid Tree |
Medium |
| 260 |
Single Number III |
Medium |
| 259 |
3Sum Smaller |
Medium |
| 258 |
Add Digits |
Easy |
| 257 |
Binary Tree Paths |
Easy |
| 256 |
Paint House |
Medium |
| 255 |
Verify Preorder Sequence in Binary Search Tree |
Medium |
| 254 |
Factor Combinations |
Medium |
| 253 |
Meeting Rooms II |
Medium |
| 252 |
Meeting Rooms |
Easy |
| 251 |
Flatten 2D Vector |
Medium |
| 250 |
Count Univalue Subtrees |
Medium |
| 249 |
Group Shifted Strings |
Easy |
| 248 |
Strobogrammatic Number III |
Medium |
| 247 |
Strobogrammatic Number II |
Medium |
| 246 |
Strobogrammatic Number |
Easy |
| 245 |
Shortest Word Distance III |
Medium |
| 244 |
Shortest Word Distance II |
Medium |
| 243 |
Shortest Word Distance |
Easy |
| 242 |
Valid Anagram |
Easy |
| 241 |
Different Ways to Add Parentheses |
Medium |
| 240 |
Search a 2D Matrix II |
Medium |
| 239 |
Sliding Window Maximum |
Hard |
| 238 |
Product of Array Except Self |
Medium |
| 237 |
Delete Node in a Linked List |
Easy |
| 236 |
Lowest Common Ancestor of a Binary Tree |
Medium |
| 235 |
Lowest Common Ancestor of a Binary Search Tree |
Easy |
| 234 |
Palindrome Linked List |
Easy |
| 233 |
Number of Digit One |
Medium |
| 232 |
Implement Queue using Stacks |
Easy |
| 231 |
Power of Two |
Easy |
| 230 |
Kth Smallest Element in a BST |
Medium |
| 229 |
Majority Element II |
Medium |
| 228 |
Summary Ranges |
Easy |
| 227 |
Basic Calculator II |
Medium |
| 226 |
Invert Binary Tree |
Easy |
| 225 |
Implement Stack using Queues |
Medium |
| 224 |
Basic Calculator - [Reverse Polish Notation] |
Medium |
| 223 |
Rectangle Area |
Easy |
| 222 |
Count Complete Tree Nodes |
Medium |
| 221 |
Maximal Square |
Medium |
| 220 |
Contains Duplicate III |
Medium |
| 219 |
Contains Duplicate II |
Easy |
| 218 |
The Skyline Problem |
Hard |
| 217 |
Contains Duplicate |
Easy |
| 216 |
Combination Sum III |
Medium |
| 215 |
Kth Largest Element in an Array |
Medium |
| 214 |
Shortest Palindrome |
Hard |
| 213 |
House Robber II |
Medium |
| 212 |
Word Search II |
Hard |
| 211 |
Add and Search Word - Data structure design |
Medium |
| 210 |
Course Schedule II |
Medium |
| 209 |
Minimum Size Subarray Sum |
Medium |
| 208 |
Implement Trie (Prefix Tree) |
Medium |
| 207 |
Course Schedule |
Medium |
| 206 |
Reverse Linked List |
Easy |
| 205 |
Isomorphic Strings |
Easy |
| 204 |
Count Primes |
Easy |
| 203 |
Remove Linked List Elements |
Easy |
| 202 |
Happy Number |
Easy |
| 201 |
Bitwise AND of Numbers Range |
Medium |
| 200 |
Number of Islands |
Medium |
| 199 |
Binary Tree Right Side View |
Medium |
| 198 |
House Robber |
Easy |
| 191 |
Number of 1 Bits |
Easy |
| 190 |
Reverse Bits |
Easy |
| 189 |
Rotate Array |
Easy |
| 188 |
Best Time to Buy and Sell Stock IV |
Hard |
| 187 |
Repeated DNA Sequences |
Medium |
| 186 |
Reverse Words in a String II |
Medium |
| 179 |
Largest Number |
Medium |
| 174 |
Dungeon Game |
Hard |
| 173 |
Binary Search Tree Iterator |
Medium |
| 172 |
Factorial Trailing Zeroes |
Easy |
| 171 |
Excel Sheet Column Number |
Easy |
| 170 |
Two Sum III - Data structure design |
Easy |
| 169 |
Majority Element |
Easy |
| 168 |
Excel Sheet Column Title |
Easy |
| 167 |
Two Sum II - Input array is sorted |
Medium |
| 166 |
Fraction to Recurring Decimal |
Medium |
| 165 |
Compare Version Numbers |
Easy |
| 164 |
Maximum Gap |
Hard |
| 163 |
Missing Ranges |
Medium |
| 162 |
Find Peak Element |
Medium |
| 161 |
One Edit Distance |
Medium |
| 160 |
Intersection of Two Linked Lists |
Easy |
| 159 |
Longest Substring with At Most Two Distinct Characters |
Hard |
| 158 |
Read N Characters Given Read4 II - Call multiple times |
Hard |
| 157 |
Read N Characters Given Read4 |
Easy |
| 156 |
Binary Tree Upside Down |
Medium |
| 155 |
Min Stack |
Easy |
| 154 |
Find Minimum in Rotated Sorted Array II |
Hard |
| 153 |
Find Minimum in Rotated Sorted Array |
Medium |
| 152 |
Maximum Product Subarray |
Medium |
| 151 |
Reverse Words in a String |
Medium |
| 150 |
Evaluate Reverse Polish Notation |
Medium |
| 149 |
Max Points on a Line |
Hard |
| 148 |
Sort List |
Medium |
| 147 |
Insertion Sort List |
Medium |
| 146 |
LRU Cache |
Hard |
| 145 |
Binary Tree Postorder Traversal |
Hard |
| 144 |
Binary Tree Preorder Traversal |
Medium |
| 143 |
Reorder List |
Medium |
| 142 |
Linked List Cycle II |
Medium |
| 141 |
Linked List Cycle |
Medium |
| 140 |
Word Break II |
Hard |
| 139 |
Word Break |
Medium |
| 138 |
Copy List with Random Pointer |
Hard |
| 137 |
Single Number II |
Medium |
| 136 |
Single Number |
Medium |
| 135 |
Candy |
Hard |
| 134 |
Gas Station |
Medium |
| 133 |
Clone Graph |
Medium |
| 132 |
Palindrome Partitioning II |
Hard |
| 131 |
Palindrome Partitioning |
Medium |
| 130 |
Surrounded Regions |
Medium |
| 129 |
Sum Root to Leaf Numbers |
Medium |
| 128 |
Longest Consecutive Sequence |
Hard |
| 127 |
Word Ladder |
Medium |
| 126 |
Word Ladder II |
Hard |
| 125 |
Valid Palindrome |
Easy |
| 124 |
Binary Tree Maximum Path Sum |
Hard |
| 123 |
Best Time to Buy and Sell Stock III |
Hard |
| 122 |
Best Time to Buy and Sell Stock II |
Medium |
| 121 |
Best Time to Buy and Sell Stock |
Medium |
| 120 |
Triangle |
Medium |
| 119 |
Pascal’s Triangle II |
Easy |
| 118 |
Pascal’s Triangle |
Easy |
| 117 |
Populating Next Right Pointers in Each Node II |
Hard |
| 116 |
Populating Next Right Pointers in Each Node |
Medium |
| 115 |
Distinct Subsequences |
Hard |
| 114 |
Flatten Binary Tree to Linked List |
Medium |
| 113 |
Path Sum II |
Medium |
| 112 |
Path Sum |
Easy |
| 111 |
Minimum Depth of Binary Tree |
Easy |
| 110 |
Balanced Binary Tree |
Easy |
| 109 |
Convert Sorted List to Binary Search Tree |
Medium |
| 108 |
Convert Sorted Array to Binary Search Tree |
Medium |
| 107 |
Binary Tree Level Order Traversal II |
Easy |
| 106 |
Construct Binary Tree from Inorder and Postorder Traversal |
Medium |
| 105 |
Construct Binary Tree from Preorder and Inorder Traversal |
Medium |
| 104 |
Maximum Depth of Binary Tree |
Easy |
| 103 |
Binary Tree Zigzag Level Order Traversal |
Medium |
| 102 |
Binary Tree Level Order Traversal |
Easy |
| 101 |
Symmetric Tree |
Easy |
| 100 |
Same Tree |
Easy |
| 99 |
Recover Binary Search Tree |
Hard |
| 98 |
Validate Binary Search Tree |
Medium |
| 97 |
Interleaving String |
Hard |
| 96 |
Unique Binary Search Trees |
Medium |
| 95 |
Unique Binary Search Trees II |
Medium |
| 94 |
Binary Tree Inorder Traversal |
Medium |
| 93 |
Restore IP Addresses |
Medium |
| 92 |
Reverse Linked List II |
Medium |
| 91 |
Decode Ways |
Medium |
| 90 |
Subsets II |
Medium |
| 89 |
Gray Code |
Medium |
| 88 |
Merge Sorted Array |
Easy |
| 87 |
Scramble String |
Hard |
| 86 |
Partition List |
Medium |
| 85 |
Maximal Rectangle |
Hard |
| 84 |
Largest Rectangle in Histogram |
Hard |
| 83 |
Remove Duplicates from Sorted List |
Easy |
| 82 |
Remove Duplicates from Sorted List II |
Medium |
| 81 |
Search in Rotated Sorted Array II |
Medium |
| 80 |
Remove Duplicates from Sorted Array II |
Medium |
| 79 |
Word Search |
Medium |
| 78 |
Subsets |
Medium |
| 77 |
Combinations |
Medium |
| 76 |
Minimum Window Substring |
Hard |
| 75 |
Sort Colors |
Medium |
| 74 |
Search a 2D Matrix |
Medium |
| 73 |
Set Matrix Zeroes |
Medium |
| 72 |
Edit Distance |
Hard |
| 71 |
Simplify Path |
Medium |
| 70 |
Climbing Stairs |
Easy |
| 69 |
Sqrt(x) |
Medium |
| 68 |
Text Justification |
Hard |
| 67 |
Add Binary |
Easy |
| 66 |
Plus One |
Easy |
| 65 |
Valid Number |
Hard |
| 64 |
Minimum Path Sum |
Medium |
| 63 |
Unique Paths II |
Medium |
| 62 |
Unique Paths |
Medium |
| 61 |
Rotate List |
Medium |
| 60 |
Permutation Sequence |
Medium |
| 59 |
Spiral Matrix II |
Medium |
| 58 |
Length of Last Word |
Easy |
| 57 |
Insert Interval |
Hard |
| 56 |
Merge Intervals |
Hard |
| 55 |
Jump Game |
Medium |
| 54 |
Spiral Matrix |
Medium |
| 53 |
Maximum Subarray |
Medium |
| 52 |
N-Queens II |
Hard |
| 51 |
N-Queens |
Hard |
| 50 |
Pow(x, n) |
Medium |
| 49 |
Anagrams |
Medium |
| 48 |
Rotate Image |
Medium |
| 47 |
Permutations II |
Hard |
| 46 |
Permutations |
Medium |
| 45 |
Jump Game II |
Hard |
| 44 |
Wildcard Matching |
Hard |
| 43 |
Multiply Strings |
Medium |
| 42 |
Trapping Rain Water |
Hard |
| 41 |
First Missing Positive |
Hard |
| 40 |
Combination Sum II |
Medium |
| 39 |
Combination Sum |
Medium |
| 38 |
Count and Say |
Easy |
| 37 |
Sudoku Solver |
Hard |
| 36 |
Valid Sudoku |
Easy |
| 35 |
Search Insert Position |
Medium |
| 34 |
Search for a Range |
Medium |
| 33 |
Search in Rotated Sorted Array |
Hard |
| 32 |
Longest Valid Parentheses |
Hard |
| 31 |
Next Permutation |
Medium |
| 30 |
Substring with Concatenation of All Words |
Hard |
| 29 |
Divide Two Integers |
Medium |
| 28 |
Implement strStr() |
Easy |
| 27 |
Remove Element |
Easy |
| 26 |
Remove Duplicates from Sorted Array |
Easy |
| 25 |
Reverse Nodes in k-Group |
Hard |
| 24 |
Swap Nodes in Pairs |
Medium |
| 23 |
Merge k Sorted Lists |
Hard |
| 22 |
Generate Parentheses |
Medium |
| 21 |
Merge Two Sorted Lists |
Easy |
| 20 |
Valid Parentheses |
Easy |
| 19 |
Remove Nth Node From End of List |
Easy |
| 18 |
4Sum |
Medium |
| 17 |
Letter Combinations of a Phone Number |
Medium |
| 16 |
3Sum Closest |
Medium |
| 15 |
3Sum |
Medium |
| 14 |
Longest Common Prefix |
Easy |
| 13 |
Roman to Integer |
Easy |
| 12 |
Integer to Roman |
Medium |
| 11 |
Container With Most Water |
Medium |
| 10 |
Regular Expression Matching |
Hard |
| 9 |
Palindrome Number |
Easy |
| 8 |
String to Integer (atoi) |
Easy |
| 7 |
Reverse Integer |
Easy |
| 6 |
ZigZag Conversion |
Easy |
| 5 |
Longest Palindromic Substring |
Medium |
| 4 |
Median of Two Sorted Arrays |
Hard |
| 3 |
Longest Substring Without Repeating Characters |
Medium |
| 2 |
Add Two Numbers |
Medium |
| 1 |
Two Sum |
Medium |