# Status Problem video Level Completes Likes 137 Populate Next Right Pointers in Each Node Hard % 0 134 Diameter Of a Binary Tree Hard % 1 129 Binary Min-Max Heap Implementation Hard % 0 123 Colorful Numbers Hard % 3 121 Print All the Subsets of a Given Set (Power Set) Hard % 1 118 Print All Combinations of subset of size K from Given Array Hard % 0 100 AVL Tree - Insertion Hard % 0 99 Construct a binary tree from given Inorder and Level Order Traversal Hard % 0 98 Construct Binary Search Tree from a given Preorder Traversal Using Stack (Without Recursion) Hard % 0 97 Construct Binary Search Tree from a given Preorder Traversal using Recursion Hard % 0 95 Construct a Binary Tree from Given Inorder and Depth-First-Search Hard % 0 93 Inorder Predecessor and Successor in Binary Search Tree Hard % 0 88 Rearrange Array: Positive and Negative Elements Alternating Hard % 0 84 Elements in an Array Occurring More Than N/K Times Hard % 0 82 Find Nodes at Distance X from a Given Node in a Tree Hard % 0 79 Calculate Distance Between Nodes in a Binary Tree Hard % 0 77 Construct a binary tree from given Inorder and Postorder Traversal Hard % 0 74 Lowest Common Ancestor in a Binary Tree (Not Binary Search Tree). Hard % 0 72 Make a Binary Tree from Given Inorder and Preorder Traversal Hard % 0 58 Generate All String Permutations Hard % 0 Populate Next Right Pointers in Each Node Diameter Of a Binary Tree Binary Min-Max Heap Implementation Colorful Numbers Print All the Subsets of a Given Set (Power Set) Print All Combinations of subset of size K from Given Array AVL Tree - Insertion Construct a binary tree from given Inorder and Level Order Traversal Construct Binary Search Tree from a given Preorder Traversal Using Stack (Without Recursion) Construct Binary Search Tree from a given Preorder Traversal using Recursion Construct a Binary Tree from Given Inorder and Depth-First-Search Inorder Predecessor and Successor in Binary Search Tree Rearrange Array: Positive and Negative Elements Alternating Elements in an Array Occurring More Than N/K Times Find Nodes at Distance X from a Given Node in a Tree Calculate Distance Between Nodes in a Binary Tree Construct a binary tree from given Inorder and Postorder Traversal Lowest Common Ancestor in a Binary Tree (Not Binary Search Tree). Make a Binary Tree from Given Inorder and Preorder Traversal Generate All String Permutations 1 2 3 4 5 6