Leetcode Solutions

C++/Shell/SQL source code of solved LeetCode problems.

List

The list is sorted by problem number.

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• 1. Two Sum
• 5. Longest Palindromic Substring
• 8. String to Integer (atoi)
• 9. Palindrome Number
• 11. Container With Most Water
• 13. Roman to Integer
• 14. Longest Common Prefix
• 17. Letter Combinations of a Phone Number
• 26. Remove Duplicates from Sorted Array
• 27. Remove Element
• 28. Find the Index of the First Occurrence in a String
• 36. Valid Sudoku
• 37. Sudoku Solver
• 41. First Missing Positive
• 42. Trapping Rain Water
• 51. N Queens
• 52. N Queens II
• 58. Length of Last Word
• 62. Unique Paths
• 63. Unique Paths II
• 64. Minimum Path Sum
• 66. Plus One
• 69. Sqrt(x)
• 70. Climbing Stairs
• 72. Edit Distance
• 76. Minimum Window Substring
• 84. Largest Rectangle in Histogram
• 85. Maximal Rectangle
• 88. Merge Sorted Array
• 91. Decode Ways
• 95. Unique Binary Search Trees II
• 96. Unique Binary Search Trees
• 97. Interleaving String
• 100. Same Tree
• 104. Maximum Depth of Binary Tree
• 115. Distinct Subsequences
• 120. Triangle
• 121. Buy and Sell Stock
• 123. Best Time to Buy and Sell Stock 3
• 124. Binary Tree Maximum Path Sum
• 125. Valid Palindrome
• 135. Candy
• 136. Single Number
• 139. Word Break
• 141. Linked List Cycle
• 144. Binary Tree Preorder Traversal
• 146. LRU Cache
• 151. Reverse Words in a String
• 162. Find Peak Element
• 169. Majority Element
• 188. Best Time to Buy and Sell Stock IV
• 192. Word Frequenc
• 193. Valid Phone Number
• 194. Transpose Fil
• 195. Tenth Lin
• 197. Rising Temperature
• 198. House Robber
• 199. Binary Tree Right Side View
• 200. Number of Islands
• 202. Happy Number
• 205. Isomorphic Strings
• 206. Reverse Linked List
• 208. Implement Trie (Prefix Tree)
• 215. Kth Largest Element in an Array
• 216. Combination Sum III
• 221. Maximal Square
• 236. Lowest Common Ancestor of a Binary Tree
• 238. Product of Array Except Self
• 242. Valid Anagram
• 279. Perfect Squares
• 283. Move Zeroes
• 300. Longest Increasing Subsequence
• 309. Best Time to Buy and Sell Stock with Cooldown
• 322. Coin Change
• 328. Odd Even Linked List
• 334. Increasing Triplet Subsequence
• 337. House Robber III
• 338. Counting Bits
• 342. Power of Four
• 343. Integer Break
• 345. Reverse Vowels of a String
• 354. Russian Doll Envelopes
• 368. Largest Divisible Subset
• 374. Guess Number Higher or Lower
• 383. Ransom Note
• 386. Lexicographical Numbers
• 392. Is Subsequence
• 394. Decode String
• 399. Evaluate Division
• 407. Trapping Rain Water II
• 415. Add Strings
• 416. Partition Equal Subset Sum
• 435. Non overlapping Intervals
• 437. Path Sum III
• 443. String Compression
• 450. Delete Node in a BST
• 452. Minimum Number of Arrows to Burst Balloons
• 455. Assign Cookies
• 474. Ones and Zeroes
• 494. Target Sum
• 509. Fibonacci Number
• 515. Find Largest Value in Each Tree Row
• 516. Longest Palindromic Subsequence
• 518. Coin Change II
• 547. Number of Provinces
• 570. Managers with at Least 5 Direct Reports
• 577. Employee Bonus
• 583. Delete Operation for Two Strings
• 584. Find Customer Referee
• 594. Longest Harmonious Subsequence
• 595. Big Countries
• 605. Can Place Flowers
• 620. Not Boring Movies
• 643. Maximum Average Subarray I
• 646. Maximum Length of Pair Chain
• 649. Dota2 Senate
• 673. Number of Longest Increasing Subsequence
• 684. Redundant Connection
• 689. Maximum Sum of 3 Non Overlapping Subarrays
• 700. Search in a Binary Search Tree
• 712. Minimum ASCII Delete Sum for Two Strings
• 714. Best Time to Buy and Sell Stock with Transaction Fee
• 717. 1 bit and 2 bit Characters
• 724. Find Pivot Index
• 735. Asteroid Collision
• 739. Daily Temperatures
• 740. Delete and Earn
• 746. Min Cost Climbing Stairs
• 756. Pyramid Transition Matrix
• 757. Set Intersection Size At Least Two
• 769. Max Chunks To Make Sorted
• 773. Sliding Puzzle
• 790. Domino and Tromino Tiling
• 802. Find Eventual Safe States
• 827. Making A Large Island
• 840. Magic Squares In Grid
• 841. Keys and Rooms
• 843. Guess the Word
• 865. Smallest Subtree with all the Deepest Nodes
• 872. Leaf Similar Trees
• 873. Length of Longest Fibonacci Subsequence
• 875. Koko Eating Bananas
• 889. Construct Binary Tree from Preorder and Postorder Traversal
• 901. Online Stock Span
• 916. Word Subsets
• 931. Minimum Falling Path Sum
• 933. Number of Recent Calls
• 944. Delete Columns to Make Sorted
• 960. Delete Columns to Make Sorted III
• 961. N Repeated Element in Size 2N Array
• 983. Minimum Cost For Tickets
• 994. Rotting Oranges
• 1004. Max Consecutive Ones III
• 1009. Complement of Base 10 Integer
• 1014. Best Sightseeing Pair
• 1015. Smallest Integer Divisible by K
• 1018. Binary Prefix Divisible By 5
• 1027. Longest Arithmetic Subsequence
• 1028. Recover a Tree From Preorder Traversal
• 1035. Uncrossed Lines
• 1068. Product Sales Analysis I
• 1070. Product Sales Analysis III
• 1071. Greatest Common Divisor of Strings
• 1072. Flip For Maximum Equal Rows
• 1079. Letter Tile Possibilities
• 1092. Shortest Common Supersequence
• 1123. Lowest Common Ancestor of Deepest Leaves
• 1137. N th Tribonacci Number
• 1143. Longest Common Subsequence
• 1148. Article Views I
• 1161. Maximum Level Sum of a Binary Tree
• 1207. Unique Number of Occurrences
• 1218. Longest Arithmetic Subsequence of Given Difference
• 1261. Find Elements in a Contaminated Binary Tree
• 1262. Greatest Sum Divisible by Three
• 1266. Minimum Time Visiting All Points
• 1267. Count Servers that Communicate
• 1268. Search Suggestions System
• 1290. Convert Binary Number in a Linked List to Integer
• 1295. Find Numbers with Even Number of Digits
• 1312. Minimum Insertion Steps to Make a String Palindrome
• 1318. Minimum Flips to Make a OR b Equal to c
• 1339. Maximum Product of Splitted Binary Tree
• 1346. Check If N and Its Double Exist
• 1351. Count Negative Numbers in a Sorted Matrix
• 1352. Product of the Last K Numbers
• 1358. Number of Substrings Containing All Three Characters
• 1368. Minimum Cost to Make at Least One Valid Path in a Grid
• 1372. Longest ZigZag Path in a Binary Tree
• 1378. Replace Employee ID With The Unique Identifier
• 1390. Four Divisors
• 1394. Find Lucky Integer in an Array
• 1399. Count Largest Group
• 1400. Construct K Palindrome Strings
• 1408. String Matching in an Array
• 1411. Number of Ways to Paint N × 3 Grid
• 1415. The kth Lexicographical String of All Happy Strings of Length n
• 1422. Maximum Score After Splitting a String
• 1431. Kids With the Greatest Number of Candies
• 1437. Check If All 1's Are at Least Length K Places Away
• 1448. Count Good Nodes in Binary Tree
• 1455. Check If a Word Occurs As a Prefix
• 1456. Maximum Number of Vowels in a Substring of Given Length
• 1458. Max Dot Product of Two Subsequences
• 1462. Course Schedule IV
• 1466. Reorder Routes to Make All Paths Lead to the City Zero
• 1475. Final Prices With a Special Discount in a Shop
• 1493. Longest Subarray of 1s After Deleting One Element
• 1513. Number of Substrings With Only 1s
• 1523. Count Odd Numbers in an Interval Range
• 1524. Number of Sub arrays With Odd Sum
• 1526. Minimum Number of Increments on Subarrays to Form a Target Array
• 1536. Minimum Swaps to Arrange a Binary Grid
• 1545. Find Kth Bit in Nth Binary String
• 1550. Three Consecutive Odds
• 1578. Minimum Time to Make Rope Colorful
• 1581. Customer Who Visited but Did Not Make Any Transactions
• 1582. Special Positions in a Binary Matrix
• 1590. Make Sum Divisible by P
• 1611. Minimum One Bit Operations to Make Integers Zero
• 1639. Number of Ways to Form a Target String Given a Dictionary
• 1652. Defuse the Bomb
• 1657. Determine if Two Strings Are Close
• 1661. Average Time of Process per Machine
• 1679. Max Number of K Sum Pairs
• 1683. Invalid Tweets
• 1689. Partitioning Into Minimum Number Of Deci Binary Numbers
• 1695. Maximum Erasure Value
• 1718. Construct the Lexicographically Largest Valid Sequence
• 1726. Tuple with Same Product
• 1732. Find the Highest Altitude
• 1749. Maximum Absolute Sum of Any Subarray
• 1752. Check if Array Is Sorted and Rotated
• 1757. Recyclable and Low Fat Products
• 1758. Minimum Changes To Make Alternating Binary String
• 1760. Minimum Limit of Balls in a Bag
• 1765. Map of Highest Peak
• 1768. Merge Strings Alternately
• 1769. Minimum Number of Operations to Move All Balls to Each Box
• 1780. Check if Number is a Sum of Powers of Three
• 1784. Check if Binary String Has at Most One Segment of Ones
• 1790. Check if One String Swap Can Make Strings Equal
• 1792. Maximum Average Pass Ratio
• 1800. Maximum Ascending Subarray Sum
• 1857. Largest Color Value in a Directed Graph
• 1861. Rotating the Box
• 1863. Sum of All Subset XOR Totals
• 1888. Minimum Number of Flips to Make the Binary String Alternating
• 1910. Remove All Occurrences of a Substring
• 1920. Build Array from Permutation
• 1925. Count Square Sum Triples
• 1926. Nearest Exit from Entrance in Maze
• 1930. Unique Length 3 Palindromic Subsequences
• 1934. Confirmation Rate
• 1964. Find the Longest Valid Obstacle Course at Each Position
• 1975. Maximum Matrix Sum
• 1980. Find Unique Binary String
• 2011. Final Value of Variable After Performing Operations
• 2016. Maximum Difference Between Increasing Elements
• 2017. Grid Game
• 2043. Simple Bank System
• 2054. Two Best Non Overlapping Events
• 2092. Find All People With Secret
• 2094. Finding 3 Digit Even Numbers
• 2095. Delete the Middle Node of a Linked List
• 2097. Valid Arrangement of Pairs
• 2109. Adding Spaces to a String
• 2110. Number of Smooth Descent Periods of a Stock
• 2116. Check if a Parentheses String Can Be Valid
• 2125. Number of Laser Beams in a Bank
• 2127. Maximum Employees to Be Invited to a Meeting
• 2130. Maximum Twin Sum of a Linked List
• 2138. Divide a String Into Groups of Size k
• 2140. Solving Questions With Brainpower
• 2141. Maximum Running Time of N Computers
• 2147. Number of Ways to Divide a Long Corridor
• 2154. Keep Multiplying Found Values by Two
• 2161. Partition Array According to Given Pivot
• 2169. Count Operations to Obtain Zero
• 2182. Construct String With Repeat Limit
• 2185. Counting Words With a Given Prefix
• 2206. Divide Array Into Equal Pairs
• 2211. Count Collisions on a Road
• 2215. Find the Difference of Two Arrays
• 2226. Maximum Candies Allocated to K Children
• 2257. Count Unguarded Cells
• 2270. Number of Ways to Split Array
• 2290. Minimum Obstacle Removal
• 2300. Successful Pairs of Spells and Potions
• 2336. Smallest Number in Infinite Set
• 2337. Move Pieces to Obtain a String
• 2342. Max Sum of a Pair With Equal Sum of Digits
• 2349. Design a Number Container System
• 2352. Equal Row and Column Pairs
• 2356. Number of Unique Subjects Taught by Each Teacher
• 2364. Count Number of Bad Pairs
• 2375. Construct Smallest Number From DI String
• 2379. Minimum Recolors to Get K Consecutive Black Blocks
• 2381. Shifting Letters II
• 2390. Removing Stars From a String
• 2401. Longest Nice Subarray
• 2402. Meeting Rooms III
• 2415. Reverse Odd Levels of Binary Tree
• 2425. Bitwise XOR of All Pairings
• 2429. Minimize XOR
• 2435. Paths in Matrix Whose Sum Is Divisible by K
• 2438. Range Product Queries of Powers
• 2460. Apply Operations to an Array
• 2461. Maximum Sum of Distinct Subarrays
• 2462. Total Cost to Hire K Workers
• 2466. Count Ways To Build Good Strings
• 2467. Most Profitable Path in a Tree
• 2471. Minimum Number of Operations to Sort a Binary Tree by Level
• 2483. Minimum Penalty for a Shop
• 2493. Divide Nodes Into the Maximum Number of Groups
• 2516. Take K of Each Character
• 2523. Closest Prime Numbers in Range
• 2528. Maximize the Minimum Powered City
• 2529. Maximum Count of Positive Integer and Negative Integer
• 2536. Increment Submatrices by One
• 2542. Maximum Subsequence Score
• 2554. Maximum Number of Integers to Choose From a Range
• 2558. Take Gifts From the Richest Pile
• 2559. Count Vowel Strings in Ranges
• 2560. House Robber IV
• 2566. Maximum Difference by Remapping a Digit
• 2570. Merge Two 2D Arrays by Summing Values
• 2577. Minimum Time to Visit a Cell
• 2579. Count Total Number of Colored Cells
• 2593. Find Score of an Array After Marking All Elements
• 2594. Minimum Time to Repair Cars
• 2654. Minimum Number of Operations to Make All Array Elements Equal to 1
• 2657. Find the Prefix Common Array of Two Arrays
• 2658. Maximum Number of Fish in a Grid
• 2661. First Completely Painted Row or Column
• 2683. Neighboring Bitwise XOR
• 2698. Find the Punishment Number of an Integer
• 2762. Continuous Subarrays
• 2779. Maximum Beauty of an Array After Applying Operation
• 2787. Ways to Express an Integer as Sum of Powers
• 2825. Make String a Subsequence Using Cyclic Increments
• 2872. Maximum Number of K Divisible Components
• 2873. Maximum Value of an Ordered Triplet I
• 2874. Maximum Value of an Ordered Triplet II
• 2894. Divisible and Non divisible Sums Difference
• 2924. Find Champion II
• 2940. Find Building Where Alice and Bob Can Meet
• 2942. Find Words Containing Character
• 2948. Make Lexicographically Smallest Array by Swapping Elements
• 2965. Find Missing and Repeated Values
• 2966. Divide Array Into Arrays With Max Difference
• 2981. Find Longest Special Substring That Occurs Thrice I
• 3042. Count Prefix and Suffix Pairs I
• 3066. Minimum Operations to Exceed Threshold Value II
• 3074. Apple Redistribution into Boxes
• 3075. Maximize Happiness of Selected Children
• 3105. Longest Strictly Increasing or Strictly Decreasing Subarray
• 3129. Find All Possible Stable Binary Arrays I
• 3136. Valid Word
• 3151. Special Array I
• 3152. Special Array II
• 3160. Find the Number of Distinct Colors Among the Balls
• 3169. Count Days Without Meetings
• 3170. Lexicographically Minimum String After Removing Stars
• 3174. Clear Digits
• 3190. Find Minimum Operations to Make All Elements Divisible by Three
• 3191. Minimum Operations to Make Binary Array Elements Equal to One I
• 3203. Find Minimum Diameter After Merging Two Trees
• 3208. Alternating Groups II
• 3217. Delete Nodes From Linked List Present in Array
• 3223. Minimum Length of String After Operations
• 3228. Maximum Number of Operations to Move Ones to the End
• 3234. Count the Number of Substrings With Dominant Ones
• 3243. Shortest Distance After Road Addition Queries I
• 3264. Final Array State After K Multiplication Operations I
• 3306. Count of Substrings Containing Every Vowel and K Consonants II
• 3318. Find X Sum of All K Long Subarrays I
• 3321. Find X Sum of All K Long Subarrays II
• 3330. Find the Original Typed String I
• 3346. Maximum Frequency of an Element After Performing Operations I
• 3349. Adjacent Increasing Subarrays Detection I
• 3354. Make Array Elements Equal to Zero
• 3356. Zero Array Transformation II
• 3370. Smallest Number With All Set Bits
• 3375. Minimum Operations to Make Array Values Equal to K
• 3381. Maximum Subarray Sum With Length Divisible by K
• 3392. Count Subarrays of Length Three With a Condition
• 3394. Check if Grid can be Cut into Sections
• 3396. Minimum Number of Operations to Make Elements in Array Distinct
• 3397. Maximum Number of Distinct Elements After Operations
• 3408. Design Task Manager
• 3417. Zigzag Grid Traversal With Skip
• 3418. Maximum Amount of Money Robot Can Earn
• 3423. Maximum Difference Between Adjacent Elements in a Circular Array
• 3432. Count Partitions with Even Sum Difference
• 3433. Count Mentions Per User
• 3442. Maximum Difference Between Even and Odd Frequency I
• 3453. Separate Squares I
• 3471. Find the Largest Almost Missing Integer
• 3472. Longest Palindromic Subsequence After at Most K Operations
• 3473. Sum of K Subarrays With Length at Least M
• 3474. Lexicographically Smallest Generated String
• 3477. Fruits Into Baskets II
• 3487. Maximum Unique Subarray Sum After Deletion
• 3488. Closest Equal Element Queries
• 3489. Zero Array Transformation IV
• 3512. Minimum Operations to Make Array Sum Divisible by K
• 3531. Count Covered Buildings
• 3541. Find Most Frequent Vowel and Consonant
• 3542. Minimum Operations to Convert All Elements to Zero
• 3562. Maximum Profit from Trading Stocks with Discounts
• 3573. Best Time to Buy and Sell Stock V
• 3577. Count the Number of Computer Unlocking Permutations
• 3578. Count Partitions With Max Min Difference at Most K
• 3583. Count Special Triplets
• 3606. Coupon Code Validator
• 3607. Power Grid Maintenance
• 3623. Count Number of Trapezoids I
• 3625. Count Number of Trapezoids II
• 3650. Minimum Cost Path with Edge Reversals
• 3652. Best Time to Buy and Sell Stock using Strategy