Skip to content

leetcode-algorithms

Group leetcode-algorithms Tele: https://t.me/+ST0unit9nTRkYjhl

Contribution guide

  • Create a directory named <problem_id>.<Name-To-Directory> under Easy/, Medium/, or Hard/.
  • Add a solution.md file inside that directory. Optional files: description.md, solution-go.md, solution-rust.md, solution-cpp.md.
  • Example layout:
Easy/350.Intersection-of-Two-Arrays-II/
├── solution.md
└── description.md

Solutions index

Total: 160 problems with at least one solution file.

Solution links use variant names when multiple approaches or languages exist (main = solution.md, others = solution-<variant>.md).

Easy (36)

Problem LeetCode Solution
100. Same Tree Link main
101. Symmetric Tree Link main
1189. Maximum Number of Balloons Link main
136. Single Number Link main
145. Binary Tree Postorder Traversal Link main
155. Min Stack Link hashmap
219. Contains Duplicate II Link hashmap · slidingwindow
222. Count Complete Tree Nodes Link main
350. Intersection of Two Arrays II Link main
590. N-ary Tree Postorder Traversal Link main
594. Longest Harmonious Subsequence Link main
860. Lemonade Change Link main
884. Uncommon Words from Two Sentences Link main
1331. Rank Transform of an Array Link main
1399. Count Largest Group Link main
1455. Check If A Word Occurs As A Prefix Of Any Word In A Sentence Link main
1475. Final Prices With A Special Discount In A Shop Link main
1486. XOR Operation in an Array Link main
1518. Water Bottles Link main
1539. Kth Missing Positive Number Link main
1550. Three Consecutive Odds Link main
1598. Crawler Log Folder Link cpp
1636. Sort Array By Increasing Frequency Link main
1684. Count The Number Of Consistent Strings Link main
1945. Sum of Digits of String After Convert Link main
2022. Convert 1D Array Into 2D Array Link main
2053. Kth Distinct String in an Array Link main
2191. Sort the Jumbled Numbers Link main
2418. Sort the People Link main
2558. Take Gifts From The Richest Pile Link main
2582. Passing The Pillow Link rust
2696. Minimum String Length After Removing Substrings Link main
3216. Lexicographically Smallest String After a Swap Link main
3314. Construct the Minimum Bitwise Array I Link main
3375. Minimum Operations to Make Array Values Equal to k Link main
3637. Trionic Array I Link main

Medium (96)

Problem LeetCode Solution
33. Search in rotated sorted array Link main
40. Combination Sum II Link main
63. Unique Paths II Link main
81. Search In Rotated Sorted Array Link main
122. Best Time to Buy and Sell Stock II Link main
128. Longest Consecutive Sequence Link main
155. Min Stack Link main
179. Largest number Link main
208. Implement trie (prefix tree) Link main
209. Minimum Size Subarray Sum Link main
238. Product of Array Except Self Link main
241. Different Ways to Add Parentheses Link main
264. Ugly Number II Link main
300. Longest Increasing Subsequence Link bottomup · greedy-patience-sort · topdown
307. Range sum query Mutable Link main
539. Minimum Time Difference Link main
567. Permutation in String Link main
624. Maximum Distance in Arrays Link main
654. Maximum Binary Tree Link main
725. Split Linked List in Parts Link main
729. My Calendar I Link main
739. Daily Temperatures Link main
763. Partition Labels Link main
790. Domino and Tromino Tiling Link main
807. Max Increase to Keep City Skyline Link main
826. Most Profit Assigning Work Link main
840. Magic Squares In Grid Link main
853. Car Fleet Link main
874. Walking Robot Simulation Link main
875. KoKo Eating Bananas Link main
885. Spiral Matrix III Link main
921. Minimum Add To Make Parentheses Valid Link main
947. Most Stones Removed with Same Row or Column Link main
959. Regions Cut By Slashes Link main
981. Time Based Key Value Store Link main
1014. Best Sightseeing Pair Link main
1038. Binary Search Tree to Greater Sum Tree Link main
1052. Grumpy Bookstore Owner Link main
1110. Delete Nodes And Return Forest Link main
1140. Stone Game II Link main
1190. Reverse Substrings Between Each Pair Of Parentheses Link main
1261. Find Elements in a Contaminated Binary Tree Link main
1310. XOR Queries of a Subarray Link main
1371. Find the Longest Substring Containing Vowels in Even Counts Link main
1382. Balance A Binary Search Tree Link main
1395. Count Number of Teams Link main
1438. Longest Continuous Subarray With Absolute Diff Less Than or Equal to Limit Link main
1482. Minimum number of days to make m bouquets Link main
1497. Check If Array Pairs Are Divisible by k Link main
1530. Number of Good Leaf Nodes Pairs Link main
1552. Magnetic Force Between Two Balls Link main
1593. Split a String Into the Max Number of Unique Substrings Link main
1605. Find Valid Matrix Given Row and Column Sums Link main
1653. Minimum Deletions to Make String Balanced Link main
1701. Average Waiting Time Link main
1717. Maximum Score From Removing Substrings Link main
1760. Minimum Limit Of Balls In A Bag Link main
1823. Find The Winner Of The Circular Game Link main
1833. Maximum Ice Cream Bars Link main
1894. Find the Student that Will Replace the Chalk Link main
1905. Count Sub Islands Link cpp · go · java
1922. Count Good Numbers Link main
1942. The Number of the Smallest Unoccupied Chair Link main
1963. Minimum Number of Swaps to Make the String Balanced Link main
1975. Maxium Matrix Sum Link main
2028. Find Missing Observations Link main
2058. Find the Minimum and Maximum Number of Nodes Between Critical Points Link main
2070. Most Beautiful Item for Each Query Link main
2096. Step By Step Directions From A Binary Tree Node To Another Link go
2109. Adding Spaces To A String Link main
2161. Partition Array According to Given Pivot Link main
2181. Merge Nodes in Between Zeros Link main
2182. Construct string with repeat limit Link main
2192. All Ancestor of a Node in a Directed Acyclic Graph Link main
2196. Create Binary Tree From Descriptions Link cpp · go · java · rust
2226. Maximum candies allocate to K children Link main
2270. Number Of Ways To Split Array Link main
2285. Maximum Total Importance of Roads Link main
2326. Spiral Matrix IV Link main
2337. Move Pieces to Obtain a String Link main
2419. Longest Subarray With Maximum Bitwise AND Link main
2461. Maximum Sum of Distinct Subarrays With Length K Link main
2491. Divide Players Into Teams of Equal Skill Link main
2501. Longest Square Streak in an Array Link main
2583. Kth Largest Sum in a Binary Tree Link main
2601. Prime Subtraction Operation Link main
2707. Extra Characters In A String Link main
2779. Maximum Beauty Of An Array After Applying Operation Link main
2825. Make String a Subsequence Using Cyclic Increments Link main
2924. Find Champion II Link main
3016. Minimum Number of Pushes to Type Word II Link main
3043. Find the Length of the Longest Common Prefix Link main
3097. Shortest Subarray With OR at Least K II Link main
3217. Delete Nodes From Linked List Present in Array Link main
3218. Minimum Cost for Cutting Cake I Link main
3254. Find the Power of K Size Subarrays I Link main

Hard (28)

Problem LeetCode Solution
11. Container With Most Water Link main
23. Merge k Sorted Lists Link main
37. Sudoku Solver Link main
41. First Missing Positive Link main
188. Best Time to Buy and Sell Stock IV Link main
212. Word Search II Link main
214. Shortest Palindrome Link main
239. Sliding Window Maximum Link main
295. Find Median from Data Stream Link main
502. IPO Link main
664. Strange Printer Link main
719. Find K th Smallest Pair Distance Link java · main
726. Number of Atoms Link go · main
773. Sliding Puzzle Link main
862. Shortest Subarray with Sum at Least K Link main
995. Minimum Number of K Consecutive Bit Flips Link main
1106. Parsing A Boolean Expression Link main
1579. Remove Max Number of Edges to Keep Graph Fully Traversable Link go · rust · main
2071. Maximum Number of Tasks You Can Assign Link main
2302. Count Subarrays With Score Less Than K Link main
2392. Build a Matrix With Conditions Link main
2416. Sum of Prefix Scores of Strings Link main
2503. Maximum Number of Points From Grid Queries Link main
2551. Put Marbles in Bags Link main
2751. Robot Collisions Link main
3219. Minimum Cost for Cutting Cake II Link main
3363. Find the Maximum Number of Fruits Collected Link main
3739. Count Subarrays With Majority Element II Link main