leet code solutions
  • Introduction
  • Solutions 1 - 50
    • 1Two Sum – Medium
    • 2 Add Two Numbers – Medium
    • 3 Longest Substring Without Repeating Characters
    • 4 Median of Two Sorted Arrays
    • 5 Longest Palindromic Substring
    • 6 ZigZag Conversion – Easy
    • 7 Reverse Integer – Easy
    • 8 String to Integer (atoi) – Easy
    • 9 Palindrome Number – Easy
    • 10 Regular Expression Matching
    • 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 – Easy
    • 20 Valid Parentheses – Easy
    • 21 Merge Two Sorted Lists – Easy
    • 22 Generate Parentheses – Medium
    • 23 Merge k Sorted Lists
    • 24 Swap Nodes in Pairs – Medium
    • 25 Reverse Nodes in k-Group
    • 26 Remove Duplicates from Sorted Array – Easy
    • 27 Remove Element – Easy
    • 28 Implement strStr() – Easy
    • 29 Divide Two Integers – Medium
    • 31 Next Permutation – Medium
    • 33 Search in Rotated Sorted Array – Hard
    • 34 Search for a Range – Medium
    • 35 Search Insert Position – Medium
    • 36 Valid Sudoku – Easy
    • 37 Sudoku Solver
    • 38 Count and Say – Easy
    • 39 Combination Sum – Medium
    • 40 Combination Sum II – Medium
    • 42 Trapping Rain Water
    • 43 Multiply Strings – Medium
    • 44 Wildcard Matching
    • 46 Permutations – Medium
    • 47 Permutations II – Medium
    • 48 Rotate Image – Medium
    • 49 Group Anagrams – Medium
    • 50 Pow(x, n) – Medium
  • Solutions 51 - 100
    • 53 Maximum Subarray – Medium
    • 54 Spiral Matrix – Medium
    • 55 Jump Game – Medium
    • 56 Merge Intervals
    • 57 Insert Interval
    • 58 Length of Last Word – Easy
    • 59 Spiral Matrix II – Medium
    • 60 Permutation Sequence – Medium
    • 61 Rotate List – Medium
    • 62 Unique Paths – Medium
    • 63 Unique Paths II – Medium
    • 64 Minimum Path Sum – Medium
    • 65 Valid Number
    • 66 Plus One – Easy
    • 67 Add Binary – Easy
    • 68 Text Justification
    • 69 Sqrt(x) – Medium
    • 70 Climbing Stairs – Easy
    • 71 Simplify Path – Medium
    • 73 Set Matrix Zeroes – Medium
    • 74 Search a 2D Matrix – Medium
    • 75 Sort Colors – Medium
    • 76 Minimum Window Substring
    • 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
    • 82 Remove Duplicates from Sorted List II – Medium
    • 83 Remove Duplicates from Sorted List – Easy
    • 85 Maximal Rectangle
    • 86 Partition List – Medium
    • 88 Merge Sorted Array
    • 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 – Medium
    • 95 Unique Binary Search Trees II – Medium
    • 98 Validate Binary Search Tree
  • Solutions 101 - 150
    • 101 Symmetric Tree – Easy
    • 102 Binary Tree Level Order Traversal – Easy
    • 103 Binary Tree Zigzag Level Order Traversal
    • 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 – Easy
    • 108 Convert Sorted Array to Binary Search Tree – Medium
    • 109 Convert Sorted List to Binary Search Tree – Medium
    • 110 Balanced Binary Tree – Easy
    • 111Minimum Depth of Binary Tree – Easy
    • 112 Path Sum – Easy
    • 113 Path Sum II – Medium
    • 114 Flatten Binary Tree to Linked List – Medium
    • 116 Populating Next Right Pointers in Each Node – Medium
    • 117 Populating Next Right Pointers in Each Node II
    • 118 Pascal’s Triangle – Easy
    • 119 Pascal’s Triangle II – Medium
    • 120 Triangle – Medium
    • 121 Best Time to Buy and Sell Stock – Medium
    • 122 Best Time to Buy and Sell Stock II – Medium
    • 123 Best Time to Buy and Sell Stock III – Hard
    • 125 Valid Palindrome – Easy
    • 127 Word Ladder – Medium
    • 128 Longest Consecutive Sequence
    • 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
    • 136 Single Number – Medium
    • 137 Single Number II – Medium
    • 138 Copy List with Random Pointer
    • 139 Word Break – Medium
    • 140 Word Break II – Hard
    • 141 Linked List Cycle – Medium
    • 142 Linked List Cycle II – Medium
    • 143 Reorder List – Medium
    • 144 Binary Tree Preorder Traversal – Medium
    • 145 Binary Tree Postorder Traversal – Hard
    • 146 LRU Cache – Hard
    • 147 Insertion Sort List – Medium
    • 148 Sort List
    • 149 Max Points on a Line
    • 150 Evaluate Reverse Polish Notation – Medium
  • Solutions 151 - 200
    • 151 Reverse Words in a String – Medium
    • 152 Maximum Product Subarray – Medium
    • 153 Find Minimum in Rotated Sorted Array – Medium
    • 155 Min Stack – Easy
    • 156 Binary Tree Upside Down – Medium
    • 157 Read N Characters Given Read4 – Easy
    • 158 Read N Characters Given Read4 II – Call multiple times Add to List QuestionEditorial Solution –
    • 159 Longest Substring with At Most Two Distinct Characters
    • 160 Intersection of Two Linked Lists – Easy
    • 161 One Edit Distance – Medium
    • 162 Find Peak Element – Medium
    • 163 Missing Ranges
    • 165 Compare Version Numbers
    • 166 Fraction to Recurring Decimal
    • 167 Two Sum II – Input array is sorted – Medium
    • 168 Excel Sheet Column Title – Easy
    • 169 Majority Element – Easy
    • 170 Two Sum III – Data structure design – Easy
    • 171 Excel Sheet Column Number – Easy
    • 172 Factorial Trailing Zeroes – Easy
    • 173 Binary Search Tree Iterator – Medium
    • 179 Largest Number – Medium
    • 186 Reverse Words in a String II – Medium
    • 187 Repeated DNA Sequences – Medium
    • 189 Rotate Array – Easy
    • 190 Java: Reverse Bits – Easy
    • 191 Number of 1 Bits – Easy
    • 198 House Robber – Easy
    • 199 Binary Tree Right Side View – Medium
    • 200 Number of Islands – Medium
  • Solutions 201 - 250
    • 201 LeetCode Java : Bitwise AND of Numbers Range – Medium
    • 202 LeetCode Java: Happy Number – Easy
    • 203 LeetCode Java: Remove Linked List Elements – Easy
    • 204 LeetCode Java: Count Primes – Easy
    • 205 LeetCode Java: Isomorphic Strings – Easy
    • 206 LeetCode Java: Reverse Linked List -Easy
    • 207 LeetCode Java: Course Schedule – Medium
    • 208 LeetCode Java: Implement Trie (Prefix Tree) – Medium
    • 209 LeetCode Java : Minimum Size Subarray Sum – Medium
    • 210 LeetCode Java: Course Schedule II – Medium
    • 211 LeetCode Java: Add and Search Word – Data structure design – Medium
    • 212 Word Search II
    • 213 House Robber II – Medium
    • 214 Shortest Palindrome
    • 215 Kth Largest Element in an Array – Medium
    • 216 Combination Sum III – Medium
    • 217 Contains Duplicate – Easy
    • 218 The Skyline Problem
    • 219 Contains Duplicate II – Medium
    • 220 Contains Duplicate III – Medium
    • 221 Maximal Square – Medium
    • 222 Count Complete Tree Nodes – Medium
    • 223 Rectangle Area – Easy
    • 224 Basic Calculator
    • 225 Implement Stack using Queues – Easy
    • 226 Invert Binary Tree – Easy
    • 227 Basic Calculator II – Medium
    • 228 Summary Ranges – Medium
    • 229 Majority Element II – Medium
    • 230 Kth Smallest Element in a BST – Medium
    • 231 Power of Two – Easy
    • 232 Implement Queue using Stacks – Easy
    • 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
    • 240 Search a 2D Matrix II – Medium
    • 241 Different Ways to Add Parentheses – Medium
    • 242 Valid Anagram – Easy
    • 243 Shortest Word Distance – Easy
    • 244 Shortest Word Distance II – Medium
    • 245 Shortest Word Distance III – Medium
    • 246 Strobogrammatic Number – Easy
    • 247 Strobogrammatic Number II
    • 248 LeetCode Java: Different Ways to Add Parentheses – Hard
    • 249 LeetCode Java: Group Shifted Strings – Easy
    • 250 LeetCode Java: Count Univalue Subtrees – Medium
  • Solutions 251 - 300
    • 251 Flatten 2D Vector
    • 252 LeetCode Java: Meeting Rooms – Easy
    • 253 Meeting Rooms II - Medium
    • 254 Factor Combinations - Medium
    • 255 Verify Preorder Sequence in Binary Search Tree - Medium
    • 256 Paint House - Medium
    • 257 Binary Tree Paths - Easy
    • 258 Add Digits - Easy
    • 259 3Sum Smaller
    • 260 Single Number III
    • 261 Graph Valid Tree
    • 263 Ugly Number
    • 264 Ugly Number II
    • 266 Palindrome Permutation
    • 267 Palindrome Permutation II
    • 268 Missing Number
    • 269 Alien Dictionary
    • 270 Closest Binary Search Tree Value
    • 271 Encode and Decode Strings
    • 272 Closest Binary Search Tree Value II
    • 273 Integer to English Words
    • 274 H-Index
    • 275 H-Index II
    • 276 Paint Fence
    • 277 Find the Celebrity
    • 278 First Bad Version
    • 279 Perfect Squares
    • 280 Wiggle Sort
    • 281 Zigzag Iterator
    • 282 Expression Add Operators
    • 283 Move Zeroes
    • 284 Peeking Iterator
    • 285 Inorder Successor in BST
    • 286 Walls and Gates
    • 288 Unique Word Abbreviation
    • 289 Game of Life
    • 290 Word Pattern
    • 291 Word Pattern II
    • 292 Nim Game
    • 293 Flip Game
    • 294 Flip Game II
    • 295 Find Median from Data Stream
    • 297 Serialize and Deserialize Binary Tree
    • 298 Binary Tree Longest Consecutive Sequence
    • 299 Bulls and Cows
  • Solutions 301 - 350
    • 301 Remove Invalid Parentheses
    • 302 Smallest Rectangle Enclosing Black Pixels
    • 303 Range Sum Query - Immutable
    • 304 Range Sum Query 2D - Immutable
    • 305 Number of Islands II
    • 306 Additive Number
    • 307 Range Sum Query - Mutable
    • 308 Range Sum Query 2D - Mutable
    • 309 Best Time to Buy and Sell Stock with Cooldown
    • 310 Minimum Height Trees
    • 311 Sparse Matrix Multiplication
    • 312 Burst Balloons
    • 313 Super Ugly Number
    • 314 Binary Tree Vertical Order Traversal
    • 315 Count of Smaller Numbers After Self
    • 316 Remove Duplicate Letters
    • 317 Shortest Distance from All Buildings
    • 318 Maximum Product of Word Lengths
    • 319 Bulb Switcher
    • 320 Generalized Abbreviation
    • 321 Create Maximum Number
    • 322 Coin Change
    • 323 Number of Connected Components in an Undirected Graph
    • 324 Wiggle Sort II
    • 325 Maximum Size Subarray Sum Equals k
    • 326 Power of Three
    • 327 Count of Range Sum
    • 328 Odd Even Linked List
    • 329 Longest Increasing Path in a Matrix
    • 330 Patching Array
    • 331 Verify Preorder Serialization of a Binary Tree
    • 332 Reconstruct Itinerary
    • 333 Largest BST Subtree
    • 334 Increasing Triplet Subsequence
    • 336 Palindrome Pairs
    • 337 House Robber III
    • 338 Counting Bits
    • 339 Nested List Weight Sum
    • 340 Longest Substring with At Most K Distinct Characters
    • 341 Flatten Nested List Iterator
    • 342 Power of Four
    • 343 Integer Break
    • 344 Reverse String
    • 345 Reverse Vowels of a String
    • 346 Moving Average from Data Stream
    • 347 Top K Frequent Elements
    • 348 Design Tic-Tac-Toe
    • 349 Intersection of Two Arrays
    • 350 Intersection of Two Arrays II
  • Solutions 351 - 400
    • 351 Android Unlock Patterns
    • 353 Design Snake Game
    • 354 Russian Doll Envelopes
    • 355 Design Twitter
    • 356 Line Reflection
    • 357 Count Numbers with Unique Digits
    • 358 Rearrange String k Distance Apart
    • 359 Logger Rate Limiter
    • 360 Sort Transformed Array
    • 361 Bomb Enemy
    • 362 Design Hit Counter
    • 363 Max Sum of Rectangle No Larger Than K
    • 364 Nested List Weight Sum II
    • 365 Water and Jug Problem
    • 366 Find Leaves of Binary Tree
    • 367 Valid Perfect Square
    • 368 Largest Divisible Subset
    • 369 Plus One Linked List
    • 370 Range Addition
    • 371 Sum of Two Integers
    • 372 Super Pow
    • 373 Find K Pairs with Smallest Sums
    • 374 Guess Number Higher or Lower
    • 375 Guess Number Higher or Lower II
    • 377 Combination Sum IV
    • 378 Kth Smallest Element in a Sorted Matrix
    • 379 Design Phone Directory
    • 380 Insert Delete GetRandom O(1)
    • 382 Linked List Random Node
    • 388 Longest Absolute File Path
    • 389 Find the Difference
    • 391 Perfect Rectangle
    • 393 UTF-8 Validation
    • 394 Decode String
    • 397 Integer Replacement
    • 398 Random Pick Index
    • 399 Evaluate Division
    • 400 Nth Digit
  • Solutions 401 - 450
    • 401 Binary Watch
    • 402 Remove K Digits
    • 404 Sum of Left Leaves
    • 406 Queue Reconstruction by Height
    • 407 Trapping Rain Water II
    • 408 Valid Word Abbreviation
    • 409 Longest Palindrome
    • 411 Minimum Unique Word Abbreviation
    • 415 Add Strings
    • 417 Pacific Atlantic Water Flow
    • 418 Sentence Screen Fitting
    • 421 Maximum XOR of Two Numbers in an Array
    • 422 Valid Word Square
    • 425 Word Squares
    • 444 Sequence Reconstruction
    • 447 Number of Boomerangs
    • 448 Find All Numbers Disappeared in an Array
    • 404 Sum of Left Leaves
    • 410 Split Array Largest Sum
    • 432 All O`one Data Structure
    • 437 Path Sum III
    • 450 Delete Node in a BST
  • Solutions 451 - 500
    • 451 Sort Characters By Frequency
    • 459 Repeated Substring Pattern
    • 460 LFU Cache
    • 461 Hamming Distance
    • 463 Island Perimeter
    • 465 Optimal Account Balancing
    • 469 Convex Polygon
    • 471 Encode String with Shortest Length
    • 474 Ones and Zeroes
    • 475 Heaters
    • 480 Sliding Window Median
    • 481 Magical String
    • 482 License Key Formatting
    • 483 Smallest Good Base
    • 484 Find Permutation
    • 485 Max Consecutive Ones
    • 486 Predict the Winner
    • 487 Max Consecutive Ones II
    • 490 The Maze
    • 493 Reverse Pairs
    • 494 Target Sum
    • 498 Diagonal Traverse
  • Solutions 501 - 550
    • 501 Find Mode in Binary Search Tree
    • 503 Next Greater Element II
    • 505 The Maze II
    • 506 Relative Ranks
    • 514 Freedom Trail
    • 515 Find Largest Value in Each Tree Row
    • 520 Detect Capital
    • 521 Longest Uncommon Subsequence I
    • 522 Longest Uncommon Subsequence II
    • 523 Continuous Subarray Sum
    • 524 Longest Word in Dictionary through Deleting
    • 525 Contiguous Array
    • 526 Beautiful Arrangement
    • 527 Word Abbreviation
    • 530 Minimum Absolute Difference in BST
    • 531 Lonely Pixel I
    • 533 Lonely Pixel II
    • 534 Design TinyURL
    • 535 Encode and Decode TinyURL
    • 541 Reverse String II
    • 542 01 Matrix
    • 543 Diameter of Binary Tree
    • 544 Output Contest Matches
    • 545 Boundary of Binary Tree
    • 549 Binary Tree Longest Consecutive Sequence II
    • 516 Longest Palindromic Subsequence
  • Solutions 551 - 600
    • 551 Student Attendance Record I
    • 552 Student Attendance Record II
    • 560 Subarray Sum Equals K
    • 562 Longest Line of Consecutive One in Matrix
    • 568 Maximum Vacation Days
    • 569 Median Employee Salary
    • 554 Brick Wall
  • Solutions 601 - 650
    • 621 Task Scheduler
    • 633 Sum of Square Numbers
    • 636 Exclusive Time of Functions
    • 637 Average of Levels in Binary Tree
    • 639 Decode Ways II
    • 642 Design Search Autocomplete System
    • 647 Palindromic Substrings
    • 648 Replace Words
  • Solutions 651 - 700
    • 653 Two Sum IV - Input is a BST
    • 689 Maximum Sum of 3 Non-Overlapping Subarrays
    • 670 Maximum Swap
    • 671 Second Minimum Node In a Binary Tree
    • 680 Valid Palindrome II
    • 690 Employee Importance
    • 692 Top K Frequent Words
    • 698 Partition to K Equal Sum Subsets
    • 699 Falling Squares
  • Solutions 701 - 750
    • 714 Best Time to Buy and Sell Stock with Transaction Fee
    • 716 Max Stack
    • 744 Find Smallest Letter Greater Than Target
    • 730 Count Different Palindromic Subsequences
    • 733 Flood Fill
    • 735 Asteroid Collision
  • Best Time to Buy and Sell Stock
Powered by GitBook
On this page

Solutions 51 - 100

53 Maximum Subarray – Medium54 Spiral Matrix – Medium55 Jump Game – Medium56 Merge Intervals57 Insert Interval58 Length of Last Word – Easy59 Spiral Matrix II – Medium60 Permutation Sequence – Medium61 Rotate List – Medium62 Unique Paths – Medium63 Unique Paths II – Medium64 Minimum Path Sum – Medium65 Valid Number66 Plus One – Easy67 Add Binary – Easy68 Text Justification69 Sqrt(x) – Medium70 Climbing Stairs – Easy71 Simplify Path – Medium73 Set Matrix Zeroes – Medium74 Search a 2D Matrix – Medium75 Sort Colors – Medium76 Minimum Window Substring77 Combinations – Medium78 Subsets – Medium79 Word Search – Medium80 Remove Duplicates from Sorted Array II – Medium81 Search in Rotated Sorted Array II82 Remove Duplicates from Sorted List II – Medium83 Remove Duplicates from Sorted List – Easy85 Maximal Rectangle86 Partition List – Medium88 Merge Sorted Array89 Gray Code – Medium90 Subsets II – Medium91 Decode Ways – Medium92 Reverse Linked List II – Medium93 Restore IP Addresses – Medium94 Binary Tree Inorder Traversal – Medium95 Unique Binary Search Trees II – Medium98 Validate Binary Search Tree
Previous50 Pow(x, n) – MediumNext53 Maximum Subarray – Medium

Last updated 2 years ago