| 1 |
Two Sum |
Easy |
| 2 |
Add Two Numbers |
Medium |
| 3 |
Longest Substring Without Repeating Characters |
Medium |
| 4 |
Median of Two Sorted Arrays |
Hard |
| 5 |
Longest Palindromic Substring |
Medium |
| 6 |
ZigZag Conversion |
Medium |
| 7 |
Reverse Integer |
Easy |
| 8 |
String to Integer (atoi) |
Medium |
| 9 |
Palindrome Number |
Easy |
| 10 |
Regular Expression Matching |
Hard |
| 11 |
Container With Most Water |
Medium |
| 12 |
Integer to Roman |
Medium |
| 13 |
Roman to Integer |
Easy |
| 14 |
Longest Common Prefix |
Easy |
| 15 |
3Sum |
Medium |
| 16 |
3Sum Closest |
Medium |
| 17 |
Letter Combinations of a Phone Number |
Medium |
| 18 |
4Sum |
Medium |
| 19 |
Remove Nth Node From End of List |
Medium |
| 20 |
Valid Parentheses |
Easy |
| 21 |
Merge Two Sorted Lists |
Easy |
| 22 |
Generate Parentheses |
Medium |
| 23 |
Merge k Sorted Lists |
Hard |
| 24 |
Swap Nodes in Pairs |
Medium |
| 25 |
Reverse Nodes in k-Group |
Hard |
| 26 |
Remove Duplicates from Sorted Array |
Easy |
| 27 |
Remove Element |
Easy |
| 28 |
Implement strStr() |
Easy |
| 29 |
Divide Two Integers |
Medium |
| 30 |
Substring with Concatenation of All Words |
Hard |
| 31 |
Next Permutation |
Medium |
| 32 |
Longest Valid Parentheses |
Hard |
| 33 |
Search in Rotated Sorted Array |
Medium |
| 34 |
Find First and Last Position of Element in Sorted Array |
Medium |
| 35 |
Search Insert Position |
Easy |
| 36 |
Valid Sudoku |
Medium |
| 37 |
Sudoku Solver |
Hard |
| 38 |
Count and Say |
Medium |
| 39 |
Combination Sum |
Medium |
| 40 |
Combination Sum II |
Medium |
| 41 |
First Missing Positive |
Hard |
| 42 |
Trapping Rain Water |
Hard |
| 43 |
Multiply Strings |
Medium |
| 44 |
Wildcard Matching |
Hard |
| 45 |
Jump Game II |
Medium |
| 46 |
Permutations |
Medium |
| 47 |
Permutations II |
Medium |
| 48 |
Rotate Image |
Medium |
| 49 |
Group Anagrams |
Medium |
| 50 |
Pow(x, n) |
Medium |
| 51 |
N-Queens |
Hard |
| 52 |
N-Queens II |
Hard |
| 53 |
Maximum Subarray |
Easy |
| 54 |
Spiral Matrix |
Medium |
| 55 |
Jump Game |
Medium |
| 56 |
Merge Intervals |
Medium |
| 57 |
Insert Interval |
Medium |
| 58 |
Length of Last Word |
Easy |
| 59 |
Spiral Matrix II |
Medium |
| 60 |
Permutation Sequence |
Hard |
| 61 |
Rotate List |
Medium |
| 62 |
Unique Paths |
Medium |
| 63 |
Unique Paths II |
Medium |
| 64 |
Minimum Path Sum |
Medium |
| 65 |
Valid Number |
Hard |
| 66 |
Plus One |
Easy |
| 67 |
Add Binary |
Easy |
| 68 |
Text Justification |
Hard |
| 69 |
Sqrt(x) |
Medium |
| 70 |
Climbing Stairs |
Easy |
| 71 |
Simplify Path |
Medium |
| 72 |
Edit Distance |
Medium |
| 73 |
Set Matrix Zeroes |
Medium |
| 74 |
Search a 2D Matrix |
Medium |
| 75 |
Sort Colors |
Medium |
| 76 |
Minimum Window Substring |
Hard |
| 77 |
Combinations |
Medium |
| 78 |
Subsets |
Medium |
| 79 |
Word Search |
Medium |
| 80 |
Remove Duplicates from Sorted Array II |
Medium |
| 81 |
Search in Rotated Sorted Array II |
Medium |
| 82 |
Remove Duplicates from Sorted List II |
Medium |
| 83 |
Remove Duplicates from Sorted List |
Easy |
| 84 |
Largest Rectangle in Histogram |
Hard |
| 85 |
Maximal Rectangle |
Hard |
| 86 |
Partition List |
Medium |
| 87 |
Scramble String |
Hard |
| 88 |
Merge Sorted Array |
Easy |
| 89 |
Gray Code |
Medium |
| 90 |
Subsets II |
Medium |
| 91 |
Decode Ways |
Medium |
| 92 |
Reverse Linked List II |
Medium |
| 93 |
Restore IP Addresses |
Medium |
| 94 |
Binary Tree Inorder Traversal |
Easy |
| 95 |
Unique Binary Search Trees II |
Medium |
| 96 |
Unique Binary Search Trees |
Medium |
| 97 |
Interleaving String |
Medium |
| 98 |
Validate Binary Search Tree |
Medium |
| 99 |
Recover Binary Search Tree |
Medium |
| 100 |
Same Tree |
Easy |
| 101 |
Symmetric Tree |
Easy |
| 102 |
Binary Tree Level Order Traversal |
Medium |
| 103 |
Binary Tree Zigzag Level Order Traversal |
Medium |
| 104 |
Maximum Depth of Binary Tree |
Easy |
| 105 |
Construct Binary Tree from Preorder and Inorder Traversal |
Medium |
| 106 |
Construct Binary Tree from Inorder and Postorder Traversal |
Medium |
| 107 |
Binary Tree Level Order Traversal II |
Medium |
| 108 |
Convert Sorted Array to Binary Search Tree |
Easy |
| 109 |
Convert Sorted List to Binary Search Tree |
Medium |
| 110 |
Balanced Binary Tree |
Easy |
| 111 |
Minimum Depth of Binary Tree |
Easy |
| 112 |
Path Sum |
Easy |
| 113 |
Path Sum II |
Medium |
| 114 |
Flatten Binary Tree to Linked List |
Medium |
| 115 |
Distinct Subsequences |
Hard |
| 116 |
Populating Next Right Pointers in Each Node |
Medium |
| 117 |
Populating Next Right Pointers in Each Node II |
Medium |
| 118 |
Pascal's Triangle |
Easy |
| 119 |
Pascal's Triangle II |
Easy |
| 120 |
Triangle |
Medium |
| 121 |
Best Time to Buy and Sell Stock |
Easy |
| 122 |
Best Time to Buy and Sell Stock II |
Medium |
| 123 |
Best Time to Buy and Sell Stock III |
Hard |
| 124 |
Binary Tree Maximum Path Sum |
Hard |
| 125 |
Valid Palindrome |
Easy |
| 126 |
Word Ladder II |
Hard |
| 127 |
Word Ladder |
Hard |
| 128 |
Longest Consecutive Sequence |
Medium |
| 129 |
Sum Root to Leaf Numbers |
Medium |
| 130 |
Surrounded Regions |
Medium |
| 131 |
Palindrome Partitioning |
Medium |
| 132 |
Palindrome Partitioning II |
Hard |
| 133 |
Clone Graph |
Medium |
| 134 |
Gas Station |
Medium |
| 135 |
Candy |
Hard |
| 136 |
Single Number |
Easy |
| 137 |
Single Number II |
Medium |
| 138 |
Copy List with Random Pointer |
Medium |
| 139 |
Word Break |
Medium |
| 140 |
Word Break II |
Hard |
| 141 |
Linked List Cycle |
Easy |
| 142 |
Linked List Cycle II |
Medium |
| 143 |
Reorder List |
Medium |
| 144 |
Binary Tree Preorder Traversal |
Easy |
| 145 |
Binary Tree Postorder Traversal |
Easy |
| 146 |
LRU Cache |
Medium |
| 147 |
Insertion Sort List |
Medium |
| 148 |
Sort List |
Medium |
| 149 |
Max Points on a Line |
Hard |
| 150 |
Evaluate Reverse Polish Notation |
Medium |
| 151 |
Reverse Words in a String |
Medium |
| 152 |
Maximum Product Subarray |
Medium |
| 153 |
Find Minimum in Rotated Sorted Array |
Medium |
| 154 |
Find Minimum in Rotated Sorted Array II |
Hard |
| 155 |
Min Stack |
Medium |
| 160 |
Intersection of Two Linked Lists |
Medium |
| 162 |
Find Peak Element |
Medium |
| 164 |
Maximum Gap |
Medium |
| 165 |
Compare Version Numbers |
Medium |
| 166 |
Fraction to Recurring Decimal |
Medium |
| 167 |
Two Sum II - Input Array Is Sorted |
Easy |
| 168 |
Excel Sheet Column Title |
Easy |
| 169 |
Majority Element |
Easy |
| 171 |
Excel Sheet Column Number |
Easy |
| 172 |
Factorial Trailing Zeroes |
Medium |
| 173 |
Binary Search Tree Iterator |
Medium |
| 174 |
Dungeon Game |
Hard |
| 179 |
Largest Number |
Medium |
| 187 |
Repeated DNA Sequences |
Medium |
| 188 |
Best Time to Buy and Sell Stock IV |
Hard |
| 189 |
Rotate Array |
Medium |
| 190 |
Reverse Bits |
Easy |
| 191 |
Number of 1 Bits |
Easy |
| 198 |
House Robber |
Medium |
| 199 |
Binary Tree Right Side View |
Medium |
| 200 |
Number of Islands |
Medium |
| 201 |
Bitwise AND of Numbers Range |
Medium |
| 202 |
Happy Number |
Easy |
| 203 |
Remove Linked List Elements |
Easy |
| 204 |
Count Primes |
Medium |
| 205 |
Isomorphic Strings |
Easy |
| 206 |
Reverse Linked List |
Easy |
| 207 |
Course Schedule |
Medium |
| 208 |
Implement Trie (Prefix Tree) |
Medium |
| 209 |
Minimum Size Subarray Sum |
Medium |
| 210 |
Course Schedule II |
Medium |
| 211 |
Design Add and Search Words Data Structure |
Medium |
| 212 |
Word Search II |
Hard |
| 213 |
House Robber II |
Medium |
| 214 |
Shortest Palindrome |
Hard |
| 215 |
Kth Largest Element in an Array |
Medium |
| 216 |
Combination Sum III |
Medium |
| 217 |
Contains Duplicate |
Easy |
| 218 |
The Skyline Problem |
Hard |
| 219 |
Contains Duplicate II |
Easy |
| 220 |
Contains Duplicate III |
Hard |
| 221 |
Maximal Square |
Medium |
| 222 |
Count Complete Tree Nodes |
Easy |
| 223 |
Rectangle Area |
Medium |
| 224 |
Basic Calculator |
Hard |
| 225 |
Implement Stack using Queues |
Easy |
| 226 |
Invert Binary Tree |
Easy |
| 227 |
Basic Calculator II |
Medium |
| 228 |
Summary Ranges |
Easy |
| 229 |
Majority Element II |
Medium |
| 230 |
Kth Smallest Element in a BST |
Medium |
| 231 |
Power of Two |
Easy |
| 232 |
Implement Queue using Stacks |
Easy |
| 233 |
Number of Digit One |
Hard |
| 234 |
Palindrome Linked List |
Easy |
| 235 |
Lowest Common Ancestor of a Binary Search Tree |
Easy |
| 236 |
Lowest Common Ancestor of a Binary Tree |
Medium |
| 237 |
Delete Node in a Linked List |
Easy |
| 238 |
Product of Array Except Self |
Medium |
| 239 |
Sliding Window Maximum |
Hard |
| 240 |
Search a 2D Matrix II |
Medium |
| 241 |
Different Ways to Add Parentheses |
Medium |
| 242 |
Valid Anagram |
Easy |
| 257 |
Binary Tree Paths |
Easy |
| 258 |
Add Digits |
Easy |
| 260 |
Single Number III |
Medium |
| 263 |
Ugly Number |
Easy |
| 264 |
Ugly Number II |
Medium |
| 268 |
Missing Number |
Easy |
| 273 |
Integer to English Words |
Hard |
| 274 |
H-Index |
Medium |
| 275 |
H-Index II |
Medium |
| 278 |
First Bad Version |
Medium |
| 279 |
Perfect Squares |
Medium |
| 282 |
Expression Add Operators |
Hard |
| 283 |
Move Zeroes |
Easy |
| 284 |
Peeking Iterator |
Medium |
| 287 |
Find the Duplicate Number |
Medium |
| 289 |
Game of Life |
Medium |
| 290 |
Word Pattern |
Easy |
| 292 |
Nim Game |
Easy |
| 295 |
Find Median from Data Stream |
Hard |
| 297 |
Serialize and Deserialize Binary Tree |
Hard |
| 299 |
Bulls and Cows |
Medium |
| 300 |
Longest Increasing Subsequence |
Medium |
| 301 |
Remove Invalid Parentheses |
Hard |
| 303 |
Range Sum Query - Immutable |
Easy |
| 304 |
Range Sum Query 2D - Immutable |
Medium |
| 306 |
Additive Number |
Medium |
| 307 |
Range Sum Query - Mutable |
Medium |
| 309 |
Best Time to Buy and Sell Stock with Cooldown |
Medium |
| 310 |
Minimum Height Trees |
Medium |
| 312 |
Burst Balloons |
Hard |
| 313 |
Super Ugly Number |
Medium |
| 315 |
Count of Smaller Numbers After Self |
Hard |
| 316 |
Remove Duplicate Letters |
Medium |
| 318 |
Maximum Product of Word Lengths |
Medium |
| 319 |
Bulb Switcher |
Medium |
| 321 |
Create Maximum Number |
Hard |
| 322 |
Coin Change |
Medium |
| 324 |
Wiggle Sort II |
Medium |
| 326 |
Power of Three |
Easy |
| 327 |
Count of Range Sum |
Hard |
| 328 |
Odd Even Linked List |
Medium |
| 329 |
Longest Increasing Path in a Matrix |
Hard |
| 330 |
Patching Array |
Hard |
| 331 |
Verify Preorder Serialization of a Binary Tree |
Medium |
| 332 |
Reconstruct Itinerary |
Hard |
| 334 |
Increasing Triplet Subsequence |
Medium |
| 335 |
Self Crossing |
Hard |
| 336 |
Palindrome Pairs |
Hard |
| 337 |
House Robber III |
Medium |
| 338 |
Counting Bits |
Easy |
| 341 |
Flatten Nested List Iterator |
Medium |
| 342 |
Power of Four |
Easy |
| 343 |
Integer Break |
Medium |
| 344 |
Reverse String |
Easy |
| 345 |
Reverse Vowels of a String |
Easy |
| 347 |
Top K Frequent Elements |
Medium |
| 349 |
Intersection of Two Arrays |
Easy |
| 350 |
Intersection of Two Arrays II |
Easy |
| 352 |
Data Stream as Disjoint Intervals |
Hard |
| 354 |
Russian Doll Envelopes |
Hard |
| 355 |
Design Twitter |
Medium |
| 357 |
Count Numbers with Unique Digits |
Medium |
| 363 |
Max Sum of Rectangle No Larger Than K |
Hard |
| 365 |
Water and Jug Problem |
Medium |
| 367 |
Valid Perfect Square |
Easy |
| 368 |
Largest Divisible Subset |
Medium |
| 371 |
Sum of Two Integers |
Medium |
| 372 |
Super Pow |
Medium |
| 373 |
Find K Pairs with Smallest Sums |
Medium |
| 374 |
Guess Number Higher or Lower |
Medium |
| 375 |
Guess Number Higher or Lower II |
Medium |
| 376 |
Wiggle Subsequence |
Medium |
| 377 |
Combination Sum IV |
Medium |
| 378 |
Kth Smallest Element in a Sorted Matrix |
Medium |
| 380 |
Insert Delete GetRandom O(1) |
Medium |
| 381 |
Insert Delete GetRandom O(1) - Duplicates allowed |
Hard |
| 382 |
Linked List Random Node |
Medium |
| 383 |
Ransom Note |
Easy |
| 384 |
Shuffle an Array |
Medium |
| 385 |
Mini Parser |
Medium |
| 386 |
Lexicographical Numbers |
Medium |
| 387 |
First Unique Character in a String |
Easy |
| 388 |
Longest Absolute File Path |
Medium |
| 389 |
Find the Difference |
Easy |
| 390 |
Elimination Game |
Medium |
| 391 |
Perfect Rectangle |
Hard |
| 392 |
Is Subsequence |
Easy |
| 393 |
UTF-8 Validation |
Medium |
| 394 |
Decode String |
Medium |
| 395 |
Longest Substring with At Least K Repeating Characters |
Medium |
| 396 |
Rotate Function |
Medium |
| 397 |
Integer Replacement |
Medium |
| 398 |
Random Pick Index |
Medium |
| 399 |
Evaluate Division |
Medium |
| 400 |
Nth Digit |
Medium |
| 401 |
Binary Watch |
Easy |
| 402 |
Remove K Digits |
Medium |
| 403 |
Frog Jump |
Hard |
| 404 |
Sum of Left Leaves |
Easy |
| 405 |
Convert a Number to Hexadecimal |
Easy |
| 406 |
Queue Reconstruction by Height |
Medium |
| 407 |
Trapping Rain Water II |
Hard |
| 409 |
Longest Palindrome |
Easy |
| 410 |
Split Array Largest Sum |
Hard |
| 412 |
Fizz Buzz |
Easy |
| 413 |
Arithmetic Slices |
Medium |
| 414 |
Third Maximum Number |
Easy |
| 415 |
Add Strings |
Easy |
| 416 |
Partition Equal Subset Sum |
Medium |
| 417 |
Pacific Atlantic Water Flow |
Medium |
| 419 |
Battleships in a Board |
Medium |
| 420 |
Strong Password Checker |
Hard |
| 421 |
Maximum XOR of Two Numbers in an Array |
Medium |
| 423 |
Reconstruct Original Digits from English |
Medium |
| 424 |
Longest Repeating Character Replacement |
Medium |
| 427 |
Construct Quad Tree |
Medium |
| 429 |
N-ary Tree Level Order Traversal |
Medium |
| 430 |
Flatten a Multilevel Doubly Linked List |
Medium |
| 432 |
All O`one Data Structure |
Hard |
| 433 |
Minimum Genetic Mutation |
Medium |
| 434 |
Number of Segments in a String |
Easy |
| 435 |
Non-overlapping Intervals |
Medium |
| 436 |
Find Right Interval |
Medium |
| 437 |
Path Sum III |
Medium |
| 438 |
Find All Anagrams in a String |
Medium |
| 440 |
K-th Smallest in Lexicographical Order |
Hard |
| 441 |
Arranging Coins |
Easy |
| 442 |
Find All Duplicates in an Array |
Medium |
| 443 |
String Compression |
Medium |
| 445 |
Add Two Numbers II |
Medium |
| 446 |
Arithmetic Slices II - Subsequence |
Hard |
| 447 |
Number of Boomerangs |
Medium |
| 448 |
Find All Numbers Disappeared in an Array |
Easy |
| 449 |
Serialize and Deserialize BST |
Medium |
| 450 |
Delete Node in a BST |
Medium |
| 451 |
Sort Characters By Frequency |
Medium |
| 452 |
Minimum Number of Arrows to Burst Balloons |
Medium |
| 453 |
Minimum Moves to Equal Array Elements |
Medium |
| 454 |
4Sum II |
Medium |
| 455 |
Assign Cookies |
Easy |
| 456 |
132 Pattern |
Medium |
| 457 |
Circular Array Loop |
Medium |
| 458 |
Poor Pigs |
Hard |
| 459 |
Repeated Substring Pattern |
Easy |
| 460 |
LFU Cache |
Hard |
| 461 |
Hamming Distance |
Easy |
| 462 |
Minimum Moves to Equal Array Elements II |
Medium |
| 463 |
Island Perimeter |
Medium |
| 464 |
Can I Win |
Medium |
| 466 |
Count The Repetitions |
Hard |
| 467 |
Unique Substrings in Wraparound String |
Medium |
| 468 |
Validate IP Address |
Medium |
| 470 |
Implement Rand10() Using Rand7() |
Medium |
| 472 |
Concatenated Words |
Hard |
| 473 |
Matchsticks to Square |
Medium |
| 474 |
Ones and Zeroes |
Medium |
| 475 |
Heaters |
Medium |
| 476 |
Number Complement |
Easy |
| 477 |
Total Hamming Distance |
Medium |
| 478 |
Generate Random Point in a Circle |
Medium |
| 479 |
Largest Palindrome Product |
Hard |
| 480 |
Sliding Window Median |
Hard |
| 481 |
Magical String |
Medium |
| 482 |
License Key Formatting |
Easy |
| 483 |
Smallest Good Base |
Hard |
| 485 |
Max Consecutive Ones |
Easy |
| 486 |
Predict the Winner |
Medium |
| 488 |
Zuma Game |
Hard |
| 491 |
Non-decreasing Subsequences |
Medium |
| 492 |
Construct the Rectangle |
Easy |
| 493 |
Reverse Pairs |
Hard |
| 494 |
Target Sum |
Medium |
| 495 |
Teemo Attacking |
Easy |
| 496 |
Next Greater Element I |
Easy |
| 497 |
Random Point in Non-overlapping Rectangles |
Medium |
| 498 |
Diagonal Traverse |
Medium |
| 500 |
Keyboard Row |
Easy |
| 501 |
Find Mode in Binary Search Tree |
Easy |
| 502 |
IPO |
Hard |
| 503 |
Next Greater Element II |
Medium |
| 504 |
Base 7 |
Easy |
| 506 |
Relative Ranks |
Easy |
| 507 |
Perfect Number |
Easy |
| 508 |
Most Frequent Subtree Sum |
Medium |
| 509 |
Fibonacci Number |
Easy |
| 513 |
Find Bottom Left Tree Value |
Medium |
| 514 |
Freedom Trail |
Hard |
| 520 |
Detect Capital |
Easy |
| 521 |
Longest Uncommon Subsequence I |
Easy |
| 530 |
Minimum Absolute Difference in BST |
Easy |
| 541 |
Reverse String II |
Easy |
| 542 |
01 Matrix |
Medium |
| 543 |
Diameter of Binary Tree |
Easy |
| 547 |
Number of Provinces |
Medium |
| 551 |
Student Attendance Record I |
Easy |
| 557 |
Reverse Words in a String III |
Easy |
| 560 |
Subarray Sum Equals K |
Medium |
| 563 |
Binary Tree Tilt |
Easy |
| 565 |
Array Nesting |
Medium |
| 566 |
Reshape the Matrix |
Easy |
| 567 |
Permutation in String |
Medium |
| 575 |
Distribute Candies |
Easy |
| 589 |
N-ary Tree Preorder Traversal |
Easy |
| 594 |
Longest Harmonious Subsequence |
Easy |
| 599 |
Minimum Index Sum of Two Lists |
Easy |
| 605 |
Can Place Flowers |
Easy |
| 606 |
Construct String from Binary Tree |
Easy |
| 617 |
Merge Two Binary Trees |
Easy |
| 621 |
Task Scheduler |
Medium |
| 628 |
Maximum Product of Three Numbers |
Easy |
| 637 |
Average of Levels in Binary Tree |
Easy |
| 643 |
Maximum Average Subarray I |
Easy |
| 645 |
Set Mismatch |
Medium |
| 648 |
Replace Words |
Medium |
| 649 |
Dota2 Senate |
Medium |
| 653 |
Two Sum IV - Input is a BST |
Easy |
| 654 |
Maximum Binary Tree |
Medium |
| 680 |
Valid Palindrome II |
Easy |
| 684 |
Redundant Connection |
Medium |
| 686 |
Repeated String Match |
Easy |
| 693 |
Binary Number with Alternating Bits |
Easy |
| 695 |
Max Area of Island |
Medium |
| 696 |
Count Binary Substrings |
Easy |
| 697 |
Degree of an Array |
Easy |
| 700 |
Search in a Binary Search Tree |
Easy |
| 701 |
Insert into a Binary Search Tree |
Medium |
| 703 |
Kth Largest Element in a Stream |
Easy |
| 704 |
Binary Search |
Easy |
| 705 |
Design HashSet |
Easy |
| 706 |
Design HashMap |
Easy |
| 713 |
Subarray Product Less Than K |
Medium |
| 714 |
Best Time to Buy and Sell Stock with Transaction Fee |
Medium |
| 717 |
1-bit and 2-bit Characters |
Easy |
| 720 |
Longest Word in Dictionary |
Medium |
| 722 |
Remove Comments |
Medium |
| 724 |
Find Pivot Index |
Easy |
| 733 |
Flood Fill |
Easy |
| 735 |
Asteroid Collision |
Medium |
| 739 |
Daily Temperatures |
Medium |
| 743 |
Network Delay Time |
Medium |
| 744 |
Find Smallest Letter Greater Than Target |
Easy |
| 745 |
Prefix and Suffix Search |
Hard |
| 746 |
Min Cost Climbing Stairs |
Easy |
| 747 |
Largest Number At Least Twice of Others |
Easy |
| 748 |
Shortest Completing Word |
Easy |
| 762 |
Prime Number of Set Bits in Binary Representation |
Easy |
| 763 |
Partition Labels |
Medium |
| 783 |
Minimum Distance Between BST Nodes |
Easy |
| 784 |
Letter Case Permutation |
Medium |
| 790 |
Domino and Tromino Tiling |
Medium |
| 791 |
Custom Sort String |
Medium |
| 796 |
Rotate String |
Easy |
| 802 |
Find Eventual Safe States |
Medium |
| 804 |
Unique Morse Code Words |
Easy |
| 819 |
Most Common Word |
Easy |
| 821 |
Shortest Distance to a Character |
Easy |
| 824 |
Goat Latin |
Easy |
| 827 |
Making A Large Island |
Hard |
| 830 |
Positions of Large Groups |
Easy |
| 831 |
Masking Personal Information |
Medium |
| 841 |
Keys and Rooms |
Medium |
| 844 |
Backspace String Compare |
Easy |
| 846 |
Hand of Straights |
Medium |
| 867 |
Transpose Matrix |
Easy |
| 868 |
Binary Gap |
Easy |
| 872 |
Leaf-Similar Trees |
Easy |
| 873 |
Length of Longest Fibonacci Subsequence |
Medium |
| 875 |
Koko Eating Bananas |
Medium |
| 876 |
Middle of the Linked List |
Easy |
| 884 |
Uncommon Words from Two Sentences |
Easy |
| 889 |
Construct Binary Tree from Preorder and Postorder Traversal |
Medium |
| 890 |
Find and Replace Pattern |
Medium |
| 901 |
Online Stock Span |
Medium |
| 905 |
Sort Array By Parity |
Easy |
| 909 |
Snakes and Ladders |
Medium |
| 912 |
Sort an Array |
Medium |
| 914 |
X of a Kind in a Deck of Cards |
Medium |
| 916 |
Word Subsets |
Medium |
| 918 |
Maximum Sum Circular Subarray |
Medium |
| 922 |
Sort Array By Parity II |
Easy |
| 925 |
Long Pressed Name |
Easy |
| 926 |
Flip String to Monotone Increasing |
Medium |
| 929 |
Unique Email Addresses |
Easy |
| 933 |
Number of Recent Calls |
Easy |
| 937 |
Reorder Data in Log Files |
Medium |
| 966 |
Vowel Spellchecker |
Medium |
| 970 |
Powerful Integers |
Easy |
| 976 |
Largest Perimeter Triangle |
Easy |
| 977 |
Squares of a Sorted Array |
Easy |
| 985 |
Sum of Even Numbers After Queries |
Easy |
| 989 |
Add to Array-Form of Integer |
Easy |
| 994 |
Rotting Oranges |
Medium |
| 997 |
Find the Town Judge |
Easy |
| 1002 |
Find Common Characters |
Easy |
| 1004 |
Max Consecutive Ones III |
Medium |
| 1005 |
Maximize Sum Of Array After K Negations |
Easy |
| 1009 |
Complement of Base 10 Integer |
Easy |
| 1010 |
Pairs of Songs With Total Durations Divisible by 60 |
Medium |
| 1022 |
Sum of Root To Leaf Binary Numbers |
Easy |
| 1023 |
Camelcase Matching |
Medium |
| 1028 |
Recover a Tree From Preorder Traversal |
Hard |
| 1037 |
Valid Boomerang |
Easy |
| 1041 |
Robot Bounded In Circle |
Medium |
| 1047 |
Remove All Adjacent Duplicates In String |
Easy |
| 1051 |
Height Checker |
Easy |
| 1071 |
Greatest Common Divisor of Strings |
Easy |
| 1079 |
Letter Tile Possibilities |
Medium |
| 1081 |
Smallest Subsequence of Distinct Characters |
Medium |
| 1092 |
Shortest Common Supersequence |
Hard |
| 1103 |
Distribute Candies to People |
Easy |
| 1108 |
Defanging an IP Address |
Easy |
| 1122 |
Relative Sort Array |
Easy |
| 1137 |
N-th Tribonacci Number |
Easy |
| 1143 |
Longest Common Subsequence |
Medium |
| 1161 |
Maximum Level Sum of a Binary Tree |
Medium |
| 1189 |
Maximum Number of Balloons |
Easy |
| 1200 |
Minimum Absolute Difference |
Easy |
| 1206 |
Design Skiplist |
Hard |
| 1207 |
Unique Number of Occurrences |
Easy |
| 1208 |
Get Equal Substrings Within Budget |
Medium |
| 1217 |
Minimum Cost to Move Chips to The Same Position |
Easy |
| 1232 |
Check If It Is a Straight Line |
Easy |
| 1233 |
Remove Sub-Folders from the Filesystem |
Medium |
| 1249 |
Minimum Remove to Make Valid Parentheses |
Medium |
| 1252 |
Cells with Odd Values in a Matrix |
Easy |
| 1261 |
Find Elements in a Contaminated Binary Tree |
Medium |
| 1267 |
Count Servers that Communicate |
Medium |
| 1268 |
Search Suggestions System |
Medium |
| 1287 |
Element Appearing More Than 25% In Sorted Array |
Easy |
| 1290 |
Convert Binary Number in a Linked List to Integer |
Easy |
| 1291 |
Sequential Digits |
Medium |
| 1292 |
Maximum Side Length of a Square with Sum Less than or Equal to Threshold |
Medium |
| 1295 |
Find Numbers with Even Number of Digits |
Easy |
| 1296 |
Divide Array in Sets of K Consecutive Numbers |
Medium |
| 1297 |
Maximum Number of Occurrences of a Substring |
Medium |
| 1304 |
Find N Unique Integers Sum up to Zero |
Easy |
| 1309 |
Decrypt String from Alphabet to Integer Mapping |
Easy |
| 1313 |
Decompress Run-Length Encoded List |
Easy |
| 1317 |
Convert Integer to the Sum of Two No-Zero Integers |
Easy |
| 1318 |
Minimum Flips to Make a OR b Equal to c |
Medium |
| 1319 |
Number of Operations to Make Network Connected |
Medium |
| 1323 |
Maximum 69 Number |
Easy |
| 1324 |
Print Words Vertically |
Medium |
| 1331 |
Rank Transform of an Array |
Easy |
| 1332 |
Remove Palindromic Subsequences |
Easy |
| 1333 |
Filter Restaurants by Vegan-Friendly, Price and Distance |
Medium |
| 1342 |
Number of Steps to Reduce a Number to Zero |
Easy |
| 1351 |
Count Negative Numbers in a Sorted Matrix |
Easy |
| 1352 |
Product of the Last K Numbers |
Medium |
| 1356 |
Sort Integers by The Number of 1 Bits |
Easy |
| 1360 |
Number of Days Between Two Dates |
Easy |
| 1365 |
How Many Numbers Are Smaller Than the Current Number |
Easy |
| 1366 |
Rank Teams by Votes |
Medium |
| 1368 |
Minimum Cost to Make at Least One Valid Path in a Grid |
Hard |
| 1372 |
Longest ZigZag Path in a Binary Tree |
Medium |
| 1374 |
Generate a String With Characters That Have Odd Counts |
Easy |
| 1380 |
Lucky Numbers in a Matrix |
Easy |
| 1389 |
Create Target Array in the Given Order |
Easy |
| 1400 |
Construct K Palindrome Strings |
Medium |
| 1402 |
Reducing Dishes |
Hard |
| 1408 |
String Matching in an Array |
Easy |
| 1410 |
HTML Entity Parser |
Medium |
| 1415 |
The k-th Lexicographical String of All Happy Strings of Length n |
Medium |
| 1431 |
Kids With the Greatest Number of Candies |
Easy |
| 1436 |
Destination City |
Easy |
| 1437 |
Check If All 1's Are at Least Length K Places Away |
Easy |
| 1443 |
Minimum Time to Collect All Apples in a Tree |
Medium |
| 1446 |
Consecutive Characters |
Easy |
| 1447 |
Simplified Fractions |
Medium |
| 1448 |
Count Good Nodes in Binary Tree |
Medium |
| 1450 |
Number of Students Doing Homework at a Given Time |
Easy |
| 1451 |
Rearrange Words in a Sentence |
Medium |
| 1455 |
Check If a Word Occurs As a Prefix of Any Word in a Sentence |
Easy |
| 1456 |
Maximum Number of Vowels in a Substring of Given Length |
Medium |
| 1460 |
Make Two Arrays Equal by Reversing Sub-arrays |
Easy |
| 1462 |
Course Schedule IV |
Medium |
| 1464 |
Maximum Product of Two Elements in an Array |
Easy |
| 1466 |
Reorder Routes to Make All Paths Lead to the City Zero |
Medium |
| 1470 |
Shuffle the Array |
Easy |
| 1472 |
Design Browser History |
Medium |
| 1475 |
Final Prices With a Special Discount in a Shop |
Easy |
| 1480 |
Running Sum of 1d Array |
Easy |
| 1481 |
Least Number of Unique Integers after K Removals |
Medium |
| 1486 |
XOR Operation in an Array |
Easy |
| 1491 |
Average Salary Excluding the Minimum and Maximum Salary |
Easy |
| 1492 |
The kth Factor of n |
Medium |
| 1493 |
Longest Subarray of 1's After Deleting One Element |
Medium |
| 1496 |
Path Crossing |
Easy |
| 1502 |
Can Make Arithmetic Progression From Sequence |
Easy |
| 1507 |
Reformat Date |
Easy |
| 1512 |
Number of Good Pairs |
Easy |
| 1519 |
Number of Nodes in the Sub-Tree With the Same Label |
Medium |
| 1524 |
Number of Sub-arrays With Odd Sum |
Medium |
| 1528 |
Shuffle String |
Easy |
| 1535 |
Find the Winner of an Array Game |
Medium |
| 1550 |
Three Consecutive Odds |
Easy |
| 1551 |
Minimum Operations to Make Array Equal |
Medium |
| 1566 |
Detect Pattern of Length M Repeated K or More Times |
Easy |
| 1576 |
Replace All ?'s to Avoid Consecutive Repeating Characters |
Medium |
| 1598 |
Crawler Log Folder |
Easy |
| 1657 |
Determine if Two Strings Are Close |
Medium |
| 1668 |
Maximum Repeating Substring |
Easy |
| 1669 |
Merge In Between Linked Lists |
Medium |
| 1672 |
Richest Customer Wealth |
Easy |
| 1679 |
Max Number of K-Sum Pairs |
Medium |
| 1716 |
Calculate Money in Leetcode Bank |
Easy |
| 1718 |
Construct the Lexicographically Largest Valid Sequence |
Medium |
| 1726 |
Tuple with Same Product |
Medium |
| 1732 |
Find the Highest Altitude |
Easy |
| 1748 |
Sum of Unique Elements |
Easy |
| 1749 |
Maximum Absolute Sum of Any Subarray |
Medium |
| 1752 |
Check if Array Is Sorted and Rotated |
Easy |
| 1764 |
Form Array by Concatenating Subarrays of Another Array |
Medium |
| 1765 |
Map of Highest Peak |
Medium |
| 1768 |
Merge Strings Alternately |
Easy |
| 1769 |
Minimum Number of Operations to Move All Balls to Each Box |
Medium |
| 1780 |
Check if Number is a Sum of Powers of Three |
Medium |
| 1790 |
Check if One String Swap Can Make Strings Equal |
Easy |
| 1791 |
Find Center of Star Graph |
Easy |
| 1800 |
Maximum Ascending Subarray Sum |
Easy |
| 1812 |
Determine Color of a Chessboard Square |
Easy |
| 1817 |
Finding the Users Active Minutes |
Medium |
| 1832 |
Check if the Sentence Is Pangram |
Easy |
| 1833 |
Maximum Ice Cream Bars |
Medium |
| 1880 |
Check if Word Equals Summation of Two Words |
Easy |
| 1886 |
Determine Whether Matrix Can Be Obtained By Rotation |
Easy |
| 1910 |
Remove All Occurrences of a Substring |
Medium |
| 1920 |
Build Array from Permutation |
Easy |
| 1926 |
Nearest Exit from Entrance in Maze |
Medium |
| 1929 |
Concatenation of Array |
Easy |
| 1930 |
Unique Length-3 Palindromic Subsequences |
Medium |
| 1935 |
Maximum Number of Words You Can Type |
Easy |
| 1980 |
Find Unique Binary String |
Medium |
| 1985 |
Find the Kth Largest Integer in the Array |
Medium |
| 1996 |
The Number of Weak Characters in the Game |
Medium |
| 2000 |
Reverse Prefix of Word |
Easy |
| 2011 |
Final Value of Variable After Performing Operations |
Easy |
| 2016 |
Maximum Difference Between Increasing Elements |
Easy |
| 2017 |
Grid Game |
Medium |
| 2027 |
Minimum Moves to Convert String |
Easy |
| 2037 |
Minimum Number of Moves to Seat Everyone |
Easy |
| 2047 |
Number of Valid Words in a Sentence |
Easy |
| 2053 |
Kth Distinct String in an Array |
Medium |
| 2085 |
Count Common Words With One Occurrence |
Easy |
| 2095 |
Delete the Middle Node of a Linked List |
Medium |
| 2099 |
Find Subsequence of Length K With the Largest Sum |
Medium |
| 2114 |
Maximum Number of Words Found in Sentences |
Easy |
| 2116 |
Check if a Parentheses String Can Be Valid |
Medium |
| 2127 |
Maximum Employees to Be Invited to a Meeting |
Hard |
| 2129 |
Capitalize the Title |
Easy |
| 2130 |
Maximum Twin Sum of a Linked List |
Medium |
| 2154 |
Keep Multiplying Found Values by Two |
Easy |
| 2161 |
Partition Array According to Given Pivot |
Medium |
| 2185 |
Counting Words With a Given Prefix |
Easy |
| 2215 |
Find the Difference of Two Arrays |
Easy |
| 2235 |
Add Two Integers |
Easy |
| 2244 |
Minimum Rounds to Complete All Tasks |
Medium |
| 2300 |
Successful Pairs of Spells and Potions |
Medium |
| 2336 |
Smallest Number in Infinite Set |
Medium |
| 2342 |
Max Sum of a Pair With Equal Sum of Digits |
Medium |
| 2349 |
Design a Number Container System |
Medium |
| 2352 |
Equal Row and Column Pairs |
Medium |
| 2364 |
Count Number of Bad Pairs |
Medium |
| 2375 |
Construct Smallest Number From DI String |
Medium |
| 2381 |
Shifting Letters II |
Medium |
| 2390 |
Removing Stars From a String |
Medium |
| 2396 |
Strictly Palindromic Number |
Medium |
| 2413 |
Smallest Even Multiple |
Easy |
| 2425 |
Bitwise XOR of All Pairings |
Medium |
| 2427 |
Number of Common Factors |
Easy |
| 2429 |
Minimize XOR |
Medium |
| 2460 |
Apply Operations to an Array |
Easy |
| 2462 |
Total Cost to Hire K Workers |
Medium |
| 2467 |
Most Profitable Path in a Tree |
Medium |
| 2469 |
Convert the Temperature |
Easy |
| 2482 |
Difference Between Ones and Zeros in Row and Column |
Medium |
| 2490 |
Circular Sentence |
Easy |
| 2493 |
Divide Nodes Into the Maximum Number of Groups |
Hard |
| 2529 |
Maximum Count of Positive Integer and Negative Integer |
Easy |
| 2535 |
Difference Between Element Sum and Digit Sum of an Array |
Easy |
| 2542 |
Maximum Subsequence Score |
Medium |
| 2570 |
Merge Two 2D Arrays by Summing Values |
Easy |
| 2618 |
Check if Object Instance of Class |
Medium |
| 2619 |
Array Prototype Last |
Easy |
| 2620 |
Counter |
Easy |
| 2621 |
Sleep |
Easy |
| 2622 |
Cache With Time Limit |
Medium |
| 2623 |
Memoize |
Medium |
| 2625 |
Flatten Deeply Nested Array |
Medium |
| 2626 |
Array Reduce Transformation |
Easy |
| 2627 |
Debounce |
Medium |
| 2629 |
Function Composition |
Easy |
| 2630 |
Memoize II |
Hard |
| 2631 |
Group By |
Medium |
| 2634 |
Filter Elements from Array |
Easy |
| 2635 |
Apply Transform Over Each Element in Array |
Easy |
| 2637 |
Promise Time Limit |
Medium |
| 2648 |
Generate Fibonacci Sequence |
Easy |
| 2649 |
Nested Array Generator |
Medium |
| 2650 |
Design Cancellable Function |
Hard |
| 2657 |
Find the Prefix Common Array of Two Arrays |
Medium |
| 2658 |
Maximum Number of Fish in a Grid |
Medium |
| 2661 |
First Completely Painted Row or Column |
Medium |
| 2665 |
Counter II |
Easy |
| 2666 |
Allow One Function Call |
Easy |
| 2667 |
Create Hello World Function |
Easy |
| 2677 |
Chunk Array |
Easy |
| 2683 |
Neighboring Bitwise XOR |
Medium |
| 2693 |
Call Function with Custom Context |
Medium |
| 2694 |
Event Emitter |
Medium |
| 2695 |
Array Wrapper |
Easy |
| 2698 |
Find the Punishment Number of an Integer |
Medium |
| 2703 |
Return Length of Arguments Passed |
Easy |
| 2704 |
To Be Or Not To Be |
Easy |
| 2705 |
Compact Object |
Medium |
| 2715 |
Timeout Cancellation |
Easy |
| 2721 |
Execute Asynchronous Functions in Parallel |
Medium |
| 2722 |
Join Two Arrays by ID |
Medium |
| 2723 |
Add Two Promises |
Easy |
| 2724 |
Sort By |
Easy |
| 2725 |
Interval Cancellation |
Easy |
| 2726 |
Calculator with Method Chaining |
Easy |
| 2727 |
Is Object Empty |
Easy |
| 2948 |
Make Lexicographically Smallest Array by Swapping Elements |
Medium |
| 3042 |
Count Prefix and Suffix Pairs I |
Easy |
| 3066 |
Minimum Operations to Exceed Threshold Value II |
Medium |
| 3105 |
Longest Strictly Increasing or Strictly Decreasing Subarray |
Easy |
| 3110 |
Score of a String |
Easy |
| 3151 |
Special Array I |
Easy |
| 3160 |
Find the Number of Distinct Colors Among the Balls |
Medium |
| 3174 |
Clear Digits |
Easy |
| 3223 |
Minimum Length of String After Operations |
Medium |
| 3392 |
Count Subarrays of Length Three With a Condition |
Easy |
| 3396 |
Minimum Number of Operations to Make Elements in Array Distinct |
Easy |
| 3397 |
Maximum Number of Distinct Elements After Operations |
Medium |
| 3402 |
Minimum Operations to Make Columns Strictly Increasing |
Easy |
| 3452 |
Sum of Good Numbers |
Easy |