LeetCode Problems from LeetCode ProblemID ProblemName Solution 6 ZigZag Conversion Click 7 Reverse Integer Click 8 String_to_Integer_atoi Click 14 Longest Common Prefix Click 19 Remove Nth Node From End of List Click 20 Valid Parentheses Click 21 Merge Two Sorted Lists Click 26 Remove Duplicates from Sorted Array Click 27 Remove Element Click 28 Implement strStr Click 36 Valid Sudoku Click 38 Count and Say Click 58 Length of Last Word Click 66 Plus One Click 67 Add Binary Click 70 Climbing Stairs Click 83 Remove Duplicates from Sorted List Click 88 Merge Sorted Array Click 100 Same Tree Click 101 Symmetric Tree Click 102 Binary Tree Level Order Traversal Click 104 Maximum Depth of Binary Tree Click 107 Binary Tree Level Order Traversal II Click 110 Balanced Binary Tree Click 112 Path Sum Click 118 Pascal s Triangle Click 119 Pascal s Triangle II Click 125 Valid Palindrome Click 155 Min Stack Click 165 Compare Version Numbers Click 168 Excel Sheet Column Title Click 169 Majority Element Click 171 Excel Sheet Column Number Click 172 Factorial Trailing Zeroes Click 189 Rotate Array Click 190 Reverse Bits Click 191 Number of 1 Bits Click 198 House Robber Click 202 Happy Number Click 203 Remove Linked List Elements Click 204 Count Primes Click 205 Isomorphic Strings Click 206 Reverse Linked List Click 217 Contains Duplicate Click 219 Contains Duplicate II Click 223 Rectangle Area Click