in this repository , I am try to practice and enhance my problem solving and coding skills by using
kotlin . this repository contains three major folders [easy - medium - hard] based on problem level, you can find the problem in every folder by problem name and number.
- 303. Range Sum Query - Immutable
- 1920. Build Array from Permutation
- 1913. Maximum Product Difference Between Two Pairs
- 653. Two Sum IV - Input is a BST
- 598. Range Addition II
- 543. Diameter of Binary Tree
- 155. Min Stack
- 226. Invert Binary Tree
- 404. Sum of Left Leaves
- 441. Arranging Coins
- 448. Find All Numbers Disappeared in an Array
- 461. Hamming Distance
- 35. Search Insert Position
- 941. Valid Mountain Array -Leetcode Link
- 1672. Richest Customer Wealth -Leetcode Link
- 121. Best Time to Buy and Sell Stock -Leetcode Link
- 389. Find the Difference -Leetcode Link
- 258. Add Digits -Leetcode Link
- 104. Maximum Depth of Binary Tree -Leetcode Link
- 136. Single Number -Leetcode Link
- 171. Excel Sheet Column Number -Leetcode Link
- 169. Majority Element -Leetcode Link
- 228. Summary Ranges -Leetcode Link
- 338. Counting Bits -Leetcode Link
- 392. Is Subsequence -Leetcode Link
- 21. Merge Two Sorted Lists -Leetcode Link
- 141. Linked List Cycle -Leetcode Link
- 20. Valid Parentheses -Leetcode Link
- 94. Binary Tree Inorder Traversal -Leetcode Link
- 344. Reverse String -Leetcode Link
- 1721. Swapping Nodes in a Linked List -Leetcode Link
- 703. Kth Largest Element in a Stream -Leetcode Link
- 682. Baseball Game -Leetcode Link
- 700. Search in a Binary Search Tree -Leetcode Link
- 905. Sort Array By Parity -Leetcode Link
- 867. Transpose Matrix -Leetcode Link
- 88. Merge Sorted Array -Leetcode Link
- 1332. Remove Palindromic Subsequences -Leetcode Link
- 283. Move Zeroes -Leetcode Link
- 367. Valid Perfect Square -Leetcode Link
- 191. Number of 1 Bits -Leetcode Link
- 231. Power of Two -Leetcode Link
- 268. Missing Number -Leetcode Link
- 2220. Minimum Bit Flips to Convert Number -Leetcode Link
- 13. Roman to Integer -Leetcode Link
- 1089. Duplicate Zeros -Leetcode Link
- 1832. Check if the Sentence Is Pangram -Leetcode Link
- 1662. Check If Two String Arrays are Equivalent -Leetcode Link
- 345. Reverse Vowels of a String -Leetcode Link
- 1323. Maximum 69 Number -Leetcode Link
- 1544. Make The String Great -Leetcode Link
- 374. Guess Number Higher or Lower -Leetcode Link
- 26. Remove Duplicates from Sorted Array -Leetcode Link
- 263. Ugly Number -Leetcode Link
- 111. Minimum Depth of Binary Tree -Leetcode Link
- 144. Binary Tree Preorder Traversal -Leetcode Link
- 145. Binary Tree Postorder Traversal -Leetcode Link
- 1207. Unique Number of Occurrences -Leetcode Link
- 1704. Determine if String Halves Are Alike -Leetcode Link
- 1945. Sum of Digits of String After Convert - leetcode link
String
Simulation
- 1684. Count the Number of Consistent Strings - leetcode link
String
Simulation
Array
Counting
- 1331. Rank Transform of an Array - leetcode link
Array
Hash Table
Sorting
- 2696. Minimum String Length After Removing Substrings - leetcode link
String
Stack
Simulation
- 1455. Check If a Word Occurs As a Prefix of Any Word in a Sentence - leetcode link
String
Two Pointer
String Matching
- 2558. Take Gifts From the Richest Pile - leetcode link
Array
Simulation
- 3264. Final Array State After K Multiplication Operations I - leetcode link
Array
Simulation
- 1448. Count Good Nodes in Binary Tree
- 91. Decode Ways
- 633. Sum of Square Numbers
- 153. Find Minimum in Rotated Sorted Array
- 437. Path Sum III
- 151. Reverse Words in a String
- 75. Sort Colors
- 130. Surrounded Regions
- 260. Single Number III
- 43. Multiply Strings
- 96. Unique Binary Search Trees
- 122. Best Time to Buy and Sell Stock II
- 62. Unique Paths
- 450. Delete Node in a BST
- 1305. All Elements in Two Binary Search Trees-Leetcode Link
- 189. Rotate Array-Leetcode Link
- 454. 4Sum II-Leetcode Link
- 525. Contiguous Array-Leetcode Link
- 80. Remove Duplicates from Sorted Array II-Leetcode Link
- 532. K-diff Pairs in an Array-Leetcode Link
- 560. Subarray Sum Equals K-Leetcode Link
- 39. Combination Sum-Leetcode Link
- 402. Remove K Digits-Leetcode Link
- 1288. Remove Covered Intervals-Leetcode Link
- 148. Sort List-Leetcode Link
- 165. Compare Version Numbers-Leetcode Link
- 662. Maximum Width of Binary Tree-Leetcode Link
- 413. Arithmetic Slices-Leetcode Link
- 799. Champagne Tower-Leetcode Link
- 740. Delete and Earn-Leetcode Link
- 2. Add Two Number-Leetcode Link
- 71. Simplify Path-Leetcode Link
- 946. Validate Stack Sequences-Leetcode Link
- 1249. Minimum Remove to Make Valid Parentheses-Leetcode Link
- 856. Score of Parentheses-Leetcode Link
- 316. Remove Duplicate Letters-Leetcode Link
- 1007. Minimum Domino Rotations For Equal Row-Leetcode Link
- 74. Search a 2D Matrix-Leetcode Link
- 347. Top K Frequent Elements-Leetcode Link
- 289. Game of Life-Leetcode Link
- 3. Longest Substring Without Repeating Characters-Leetcode Link
- 167. Two Sum II - Input Array Is Sorted -Leetcode Link
- 5. Longest Palindromic Substring -Leetcode Link
- 820. Short Encoding of Words -Leetcode Link
- 215. Kth Largest Element inin an Array -Leetcode Link
- 1689. Partitioning Into Minimum Number Of Deci-Binary Numbers -Leetcode Link
- 199. Binary Tree Right Side View -Leetcode Link
- 473. Matchsticks to Square -Leetcode Link
- 102. Binary Tree Level Order Traversal -Leetcode Link
- 114. Flatten Binary Tree to Linked List -Leetcode Link
- 890. Find and Replace Pattern -Leetcode Link
- 729. My Calendar I -Leetcode Link
- 98. Validate Binary Search Tree -Leetcode Link
- 1318. Minimum Flips to Make a OR b Equal to c -Leetcode Link
- 237. Delete Node in a Linked List -Leetcode Link
- 38. Count and Say -Leetcode Link
- 692. Top K Frequent Words -Leetcode Link
- 12. Integer to Roman -Leetcode Link
- 1239. Maximum Length of a Concatenated String with Unique Characters -Leetcode Link
- 523. Continuous Subarray Sum -Leetcode Link
- 49. Group Anagrams -Leetcode Link
- 1706. Where Will the Ball Fall -Leetcode Link
- 433. Minimum Genetic Mutation -Leetcode Link
- 2131. Longest Palindrome by Concatenating Two Letter Words -Leetcode Link
- 901. Online Stock Span -Leetcode Link
- 222. Count Complete Tree Nodes -Leetcode Link
- 223. Rectangle Area -Leetcode Link
- 1926. Nearest Exit from Entrance in Maze -Leetcode Link
- 79. Word Search -Leetcode Link
- 2225. Find Players With Zero or One Losses -Leetcode Link
- 926. Flip String to Monotone Increasing -Leetcode Link
- 1905. Count Sub Islands- Leetcode Link
BFS
- 947. Most Stones Removed with Same Row or Column- Leetcode Link
Graph
DFS
BFS
- 1894. Find the Student that Will Replace the Chalk - Leetcode link
Prefix Sum
- 874. Walking Robot Simulation - Leetcode link
Array
Hash Table
Simulation
- 3217. Delete Nodes From Linked List Present in Array - Leetcode link
Array
Hash Table
Linked List
- 2326. Spiral Matrix IV - Leetcode link
Array
Hash Table
Linked List
- 2707. Extra Characters in a String - Leetcode link
Array
Hash Table
Dynamic Programming
Recurrsion
- 3043. Find the Length of the Longest Common Prefix - Leetcode link
Array
Hash Table
String
Trie
- 731. My Calendar II - Leetcode link
Array
Binary search
Design
Segment Tree
Prefix Sum
Ordered Set
- 1497. Check If Array Pairs Are Divisible by k - Leetcode link
Array
Hash Table
Counting
- 2491. Divide Players Into Teams of Equal Skill - Leetcode link
Array
Hash Table
Sorting
Two Pointers
- 1963. Minimum Number of Swaps to Make the String Balanced - Leetcode link
Stack
String
Two Pointers
- 921. Minimum Add to Make Parentheses Valid - Leetcode link
Stack
String
Two Pointers
- 1942. The Number of the Smallest Unoccupied Chair - Leetcode link
Array
Hash Table
Heap(Priority Queue)
- 1593. Split a String Into the Max Number of Unique Substrings - Leetcode link
Array
Hash Table
Heap(Priority Queue)
- 2583. Kth Largest Sum in a Binary Tree - Leetcode link
Tree
BFS
Sorting
Binary Tree
- 951.Flip Equivalent Binary Trees - Leetcode link
Tree
DFS
Binary Tree
- 1233. Remove Sub-Folders from the Filesystem - Leetcode link
String
Array
Sorting
- 2501. Longest Square Streak in an Array - Leetcode link
Hash Table
Array
Sorting
Binary Search
- 2684. Maximum Number of Moves in a Grid - Leetcode link
Hash Table
Array
Sorting
Binary Search
- 2275. Largest Combination With Bitwise AND Greater Than Zero - Leetcode link
Hash Table
Array
Bit Manipulation
Counting
- 2337. Move Pieces to Obtain a String - Leetcode link
Hash Table
Array
Bit Manipulation
Counting
- 2554. Maximum Number of Integers to Choose From a Range I - Leetcode link
Hash Table
Array
Binary Search
Greedy
- 2593. Find Score of an Array After Marking All Elements - Leetcode link
Hash Table
Array
Sorting
Heap(Priority Queue
- 76. Minimum Window Substring
- 2290. Minimum Obstacle Removal to Reach CornerLeetcode link
Array
Breadth-First-Search
Graph
Heap(Priority Queue)
Matrix
Shortest Path