My Solutions to Leetcode questions The title column contains links to the leetcode question. The language column contains links to my solution file. Number Title Language Difficulty 1 Two Sum C Easy 2 Add Two Numbers C Medium 3 Longest Substring Without Repeating Characters C Medium 5 Longest Palindromic Substring C Easy 6 Zigzag Conversion C Medium 7 Reverse Integer C Medium 8 String to Integer ATOI C Medium 9 Palindrome Number C Easy 11 Container With Most Water C Medium 13 Roman to Integer C Easy 14 Longest Common Prefix C Easy 15 3Sum C Medium 19 Remove Nth Node From End of List C Medium 20 Valid Parentheses C Easy 21 Merge Two Sorted Lists C Easy 26 Remove Duplicates from Sorted Array C Easy 27 Remove Element C Easy 28 Implement strStr C Easy 35 Search Input Position C Easy 53 Maximum Subarray C Easy 58 Length of Last Word C Easy 66 Plus One C Easy 67 Add Binary C Easy 70 Climbing Stairs C Easy 79 Word Search C Medium 83 Remove Duplicates From Sorted List C Easy 88 Merge Sorted Array C Easy 94 Binary Tree Inorder Traversal C Easy 100 Same Tree C Easy 101 Symmetric Tree C Easy 102 Binary Tree Level Order Traversal C Medium 104 Maximum Depth of Binary Tree C Easy 108 Convert Sorted Array to Binary Search Tree C Easy 110 Balanced Binary Tree C Easy 111 Minimum Depth of Binary Tree C Easy 112 Path Sum C Easy 121 Best Time to Buy and Sell Stock C Easy 125 Valid Palindrome C Easy 136 Single Number C Easy 141 Linked List Cycle C Easy 144 Binary Tree Preorder Traversal C Easy 145 Binary Tree Postorder Traversal C Easy 155 Min Stack C Easy 160 Intersection of Two Linked Lists C Easy 167 Two Sum II Input Array is Sorted C Medium 169 Majority Element Python Easy 176 Second Highest Salary SQL Medium 203 Remove Linked List Elements C Easy 206 Reverse Linked List C Easy 215 Kth Largest Element in an Array C Medium 226 Invert Binary Tree C Easy 268 Missing Number C Easy 283 Move Zeroes C Easy 383 Ransom Note C Easy 392 Is Subsequence C Easy 401 Binary Watch C Easy 509 Fibonacci Number C Easy 662 Maximum Width of Binary Tree C Medium 697 Degree of an Array Python Easy 1154 Day of the Year C Easy 1656 Design an Ordered Stream C Easy