LeetCode Solutions ID Link to description Link to solution 1 Two Sum Solution 2 Add Two Numbers Solution 3 Longest Substring Without Repeating Characters Solution 4 Median of Two Sorted Arrays Solution 6 Zigzag Conversion Solution 14 Longest Common Prefix Solution 19 Remove Nth Node From End of List Solution 20 Valid Parentheses Solution 21 Merge Two Sorted Lists Solution 28 Find the Index of the First Occurrence in a String Solution 32 Longest Valid Parenthesess Solution 35 Search Insert Position Solution 36 Valid Sudoku Solution 53 Maximum Subarray Solution 55 Jump Game Solution 57 Insert Interval Solution 62 Unique Paths Solution 64 Minimum Path Sum Solution 70 Climbing Stairs Solution 77 Combinations Solution 83 Remove Duplicates from Sorted List Solution 88 Merge Sorted Array Solution 91 Decode Ways Solution 93 Restore IP Addresses Solution 94 Binary Tree Inorder Traversal Solution 98 Validate Binary Search Tree Solution 100 Same Tree Solution 101 Symmetric Tree Solution 102 Binary Tree Level Order Traversal Solution 104 Maximum Depth of Binary Tree Solution 112 Path Sum Solution 116 Populating Next Right Pointers in Each Node Solution 118 Pascal's Triangle Solution 119 Pascal's Triangle II Solution 120 Triangle Solution 121 Best Time to Buy and Sell Stock Solution 124 Binary Tree Maximum Path Sum Solution 131 Palindrome Partitioning Solution 134 Gas Station Solution 136 Single Number Solution 141 Linked List Cycle Solution 142 Linked List Cycle II Solution 145 Binary Tree Postorder Traversal Solution 149 Max Points on a Line Solution 150 Evaluate Reverse Polish Notation Solution 167 Two Sum II - Input Array Is Sorted Solution 189 Rotate Array Solution 190 Reverse Bits Solution 191 Number of 1 Bits Solution 198 House Robber Solution 200 Number of Islands Solution 203 Remove Linked List Elements Solution 205 Isomorphic Strings Solution 206 Reverse Linked List Solution 217 Contains Duplicate Solution 226 Invert Binary Tree Solution 231 Power of Two Solution 232 Implement Queue using Stacks Solution 235 Lowest Common Ancestor of a Binary Search Tree Solution 242 Valid Anagram Solution 278 First Bad Version Solution 283 Move Zeroes Solution 290 Word Pattern Solution 299 Bulls and Cows Solution 309 Best Time to Buy and Sell Stock with Cooldown Solution 328 Odd Even Linked List Solution 344 Reverse String Solution 350 Intersection of Two Arrays II Solution 352 Data Stream as Disjoint Intervals Solution 383 Ransom Note Solution 387 First Unique Character in a String Solution 392 Is Subsequence Solution 394 Decode String Solution 409 Longest Palindrome Solution 424 Longest Repeating Character Replacement Solution 438 Find All Anagrams in a String Solution 451 Sort Characters By Frequency Solution 452 Minimum Number of Arrows to Burst Balloons Solution 455 Assign Cookies Solution 472 Concatenated Words Solution 509 Fibonacci Number Solution 520 Detect Capital Solution 542 01 Matrix Solution 557 Reverse Words in a String III Solution 566 Reshape the Matrix Solution 567 Permutation in String Solution 589 N-ary Tree Preorder Traversal Solution 617 Merge Two Binary Trees Solution 653 Two Sum IV - Input is a BST Solution 661 Image Smoother Solution 692 Top K Frequent Words Solution 695 Max Area of Island Solution 700 Search in a Binary Search Tree Solution 701 Insert into a Binary Search Tree Solution 704 Binary Search Solution 724 Find Pivot Index Solution 733 Flood Fill Solution 739 Daily Temperatures Solution 746 Min Cost Climbing Stairs Solution 784 Letter Case Permutation Solution 787 Cheapest Flights Within K Stops Solution 790 Domino and Tromino Tiling Solution 797 All Paths From Source to Target Solution 834 Sum of Distances in Tree Solution 837 New 21 Game Solution 841 Keys and Rooms Solution 844 Backspace String Compare Solution 872 Leaf-Similar Trees Solution 876 Middle of the Linked List Solution 886 Possible Bipartition Solution 909 Snakes and Ladders Solution 918 Maximum Sum Circular Subarray Solution 926 Flip String to Monotone Increasing Solution 931 Minimum Falling Path Sum Solution 938 Range Sum of BST Solution 944 Delete Columns to Make Sorted Solution 947 Most Stones Removed with Same Row or Column Solution 953 Verifying an Alien Dictionary Solution 974 Subarray Sums Divisible by K Solution 977 Squares of a Sorted Array Solution 980 Unique Paths III Solution 994 Rotting Oranges Solution 997 Find the Town Judge Solution 1026 Maximum Difference Between Node and Ancestor Solution 1046 Last Stone Weight Solution 1061 Lexicographically Smallest Equivalent String Solution 1071 Greatest Common Divisor of Strings Solution 1137 N-th Tribonacci Number Solution 1143 Longest Common Subsequence Solution 1235 Maximum Profit in Job Scheduling Solution 1339 Maximum Product of Splitted Binary Tree Solution 1443 Minimum Time to Collect All Apples in a Tree Solution 1470 Shuffle the Array Solution 1480 Running Sum of 1d Array Solution 1519 Number of Nodes in the Sub-Tree With the Same Label Solution 1531 String Compression II Solution 1567 Maximum Length of Subarray With Positive Product Solution 1603 Design Parking System Solution 1624 Largest Substring Between Two Equal Characters Solution 1626 Best Team With No Conflicts Solution 1657 Determine if Two Strings Are Close Solution 1704 Determine if String Halves Are Alike Solution 1751 Maximum Number of Events That Can Be Attended II Solution 1833 Maximum Ice Cream Bars Solution 1834 Single-Threaded CPU Solution 1897 Redistribute Characters to Make All Strings Equal Solution 1936 Add Minimum Number of Rungs Solution 1962 Remove Stones to Minimize the Total Solution 1971 Find if Path Exists in Graph Solution 2008 Maximum Earnings From Taxi Solution 2054 Two Best Non-Overlapping Events Solution 2244 Minimum Rounds to Complete All Tasks Solution 2246 Longest Path With Different Adjacent Characters Solution 2256 Minimum Average Difference Solution 2279 Maximum Bags With Full Capacity of Rocks Solution 2359 Find Closest Node to Given Two Nodes Solution 2389 Longest Subsequence With Limited Sum Solution 2421 Number of Good Paths Solution 2496 Maximum Value of a String in an Array Solution 2497 Maximum Star Sum of a Graph Solution 2498 Frog Jump II Solution 2500 Delete Greatest Value in Each Row Solution 2501 Longest Square Streak in an Array Solution 2502 Design Memory Allocator Solution 2503 Maximum Number of Points From Grid Queries Solution 2511 Maximum Enemy Forts That Can Be Captured Solution 2512 Reward Top K Students Solution 2513 Minimize the Maximum of Two Arrays Solution 2514 Count Anagrams Solution 2525 Categorize Box According to Criteria Solution 2526 Find Consecutive Integers from a Data Stream Solution 2527 Find Xor-Beauty of Array Solution 2540 Minimum Common Value Solution 2541 Minimum Operations to Make Array Equal II Solution 2542 Maximum Subsequence Score Solution