leetcode JavaScript Solutions problem on leet code solution tags youtube video 110. Balanced Binary Tree solution easy, bfs, trees 102. Binary Tree Level Order Traversal solution Medium, bfs, trees 107. Binary Tree Level Order Traversal II solution easy, bfs, trees 101. Symmetric Tree solution easy, dfs, trees 103. Binary Tree Zigzag Level Order Traversal solution Medium, bfs, trees 199. Binary Tree Right Side View solution Medium, bfs, trees 111. Minimum Depth of Binary Tree solution Easy, dfs, trees 112. Path Sum solution Easy, bfs, trees 113. Path Sum II solution Medium, bfs, backtrack, trees 114. Flatten Binary Tree to Linked List solution Medium, bfs, trees 100. Same Tree solution Easy, trees, bfs 110. Balanced Binary Tree solution easy, tree, dfs 1. Two Sum solution Easy, HashTable 136. Single Number solution Easy, HashTable 202. Happy Number solution Easy, Math, HashTable 217. Contains Duplicate solution Easy, HashTable, Sets 219. Contains Duplicate II solution Easy, HashTable 1207. Unique Number of Occurrences solution Easy, HashTable 13. Roman to Integer solution Easy, Strings 151. Reverse Words in a String solution Medium, Strings 14. Longest Common Prefix solution Easy, Strings 67. Add Binary solution Easy, Strings 22. Generate Parentheses solution Medium, Backtrack, Strings 53. Maximum Subarray solution Easy, Dynamic Programming 121. Best Time to Buy and Sell Stock solution Easy, Dynamic Programming 122. Best Time to Buy and Sell Stock II solution Easy, Dynamic Programming 62. Unique Paths solution Medium, Dynamic Programming 120. Triangle solution Medium, Dynamic Programming 300. Longest Increasing Subsequence solution 1, solution 2 Medium, Dynamic Programming 322. Coin Change solution Medium, Dynamic Programming 518. Coin Change 2 solution Medium, Dynamic Programming https://youtu.be/b-8MBeJBk8Q 72. Edit Distance solution Hard, Dynamic Programming https://youtu.be/PzKkjix7Mhk 1402. Reducing Dishes solution Hard, Dynamic Programming 49. Group Anagrams solution Medium, HashTable 283. Move Zeroes solution Easy, Array 844. Backspace String Compare solution Easy, String, Stack 155. Min Stack solution Easy, Array, Stack 543. Diameter of Binary Tree solution Easy, Trees, DFS 5. Longest Palindromic Substring solution Medium, Strings 144. Binary Tree Preorder Traversal solution Medium, dfs, trees 94. Binary Tree Inorder Traversal solution Medium, dfs, trees 739. Daily Temperatures solution Medium, Stack, Arrays 3. Longest Substring Without Repeating Characters solution Medium, String, Arrays 2. Add Two Numbers solution Medium, LinkedList 46. Permutations solution Medium, Backtracking https://youtu.be/o_U2ctVnH2g 47. Permutations II solution Medium, Backtracking https://youtu.be/F30kIMXls9U 39. Combination Sum solution Medium, Backtracking https://youtu.be/2kWl_LRrUEc 40. Combination Sum II solution Medium, Backtracking https://youtu.be/2kWl_LRrUEc 216. Combination Sum III solution Medium, Backtracking 51. N-Queens solution Hard, Backtracking https://youtu.be/4gS86fJHBbg 52. N-Queens II solution Hard, Backtracking https://youtu.be/4gS86fJHBbg 230. Kth Smallest Element in a BST solution Medium, Binary Search Tree, dfs 56. Merge Intervals solution Medium, Arrays 133. Clone Graph solution Medium, Graph 841. Keys and Rooms solution Medium, Graph 797. All Paths From Source to Target solution Medium, Graph, Backtracking https://youtu.be/2nU4OxMovOY 17. Letter Combinations of a Phone Number solution Medium, Graph, Backtracking 242. Valid Anagram solution Easy, Hash Table, string 704. Binary Search solution Easy, Binary search 1768. Merge Strings Alternately solution Easy, Arrays 1431. Kids With the Greatest Number of Candies solution Easy, Arrays 1071. Greatest Common Divisor of Strings solution Easy, Strings 128. Longest Consecutive Sequence solution Medium, Array 347. Top K Frequent Elements solution Medium, Hash table 238. Product of Array Except Self solution Medium, Array 125. Valid Palindrome solution Easy, String, TwoPointers 167. Two Sum II - Input Array Is Sorted solution Easy, BinarySearch, TwoPointers 11. Container With Most Water solution Medium, Greedy, TwoPointers 15. 3Sum solution Medium, Sorting, TwoPointers