# Status Problem video Level Completes Likes 134 Diameter Of a Binary Tree Hard % 1 132 Find the Deepest Node in a Binary Tree Medium % 1 125 Find the Increasing Triplet Sub-sequence in an array Medium % 0 121 Print All the Subsets of a Given Set (Power Set) Hard % 1 116 Generate All Balanced Parentheses Combinations (N Pairs) Medium % 1 112 Generate All n-Bit Binary Strings Medium % 1 108 Queue with Stacks: Efficient Implementation Using Stack Operations Medium % 0 106 Reverse a Doubly-Linked List (In-place Algorithm) Medium % 0 102 Merge Sort for Linked Lists (In-place Algorithm) Medium % 0 101 Merge a Linked list into another Linked List at Alternate Positions Medium % 0 99 Construct a binary tree from given Inorder and Level Order Traversal Hard % 0 96 Print The Top View of a Binary Tree Medium % 0 93 Inorder Predecessor and Successor in Binary Search Tree Hard % 0 88 Rearrange Array: Positive and Negative Elements Alternating Hard % 0 86 Find Kth Smallest or Largest element in an Array Medium % 0 83 Find Element in Rotated Sorted Array Medium % 0 82 Find Nodes at Distance X from a Given Node in a Tree Hard % 0 81 Find Nodes X Levels Up from Leaf Nodes in a Tree Medium % 0 80 Find Nodes at Distance X from Root in a Tree Medium % 0 74 Lowest Common Ancestor in a Binary Tree (Not Binary Search Tree). Hard % 0 73 Lowest Common Ancestor in a Binary Search Tree. Medium % 0 69 Convert Sorted Singly Linked List to Balanced Binary Search Tree Medium % 1 65 Given a binary tree, Find the Maximum Path Sum between Any Two Leaves Medium % 0 57 Sort an Array According to the Order Defined by Another Array Medium % 0 56 Sort an Array - odd numbers appear first in ascending order followed by the even numbers in descending order. Medium % 0 51 Print Binary Tree Nodes in Zigzag Order: Spiral Traversal Pattern Hard % 0 50 Find the first repeated element in an array by its index Medium % 0 46 Check if One Binary Tree is a Subtree of Another Medium % 0 40 In a Binary Tree, Create Linked Lists of all the nodes at each depth Hard % 0 39 Level Order Traversal, Print each level in separate line Medium % 0 30 Swap Every Kth Node in a LinkedList Medium % 0 27 Remove Duplicates from an Unsorted Linked list Beginner % 0 25 String Compression using count of repeated characters - Run Length Encoding Beginner % 0 24 Replace Spaces with '%20' Without Using Default Functions Medium % 0 23 Find Whether Two Strings are Permutation of each other Beginner % 1 Diameter Of a Binary Tree Find the Deepest Node in a Binary Tree Find the Increasing Triplet Sub-sequence in an array Print All the Subsets of a Given Set (Power Set) Generate All Balanced Parentheses Combinations (N Pairs) Generate All n-Bit Binary Strings Queue with Stacks: Efficient Implementation Using Stack Operations Reverse a Doubly-Linked List (In-place Algorithm) Merge Sort for Linked Lists (In-place Algorithm) Merge a Linked list into another Linked List at Alternate Positions Construct a binary tree from given Inorder and Level Order Traversal Print The Top View of a Binary Tree Inorder Predecessor and Successor in Binary Search Tree Rearrange Array: Positive and Negative Elements Alternating Find Kth Smallest or Largest element in an Array Find Element in Rotated Sorted Array Find Nodes at Distance X from a Given Node in a Tree Find Nodes X Levels Up from Leaf Nodes in a Tree Find Nodes at Distance X from Root in a Tree Lowest Common Ancestor in a Binary Tree (Not Binary Search Tree). Lowest Common Ancestor in a Binary Search Tree. Convert Sorted Singly Linked List to Balanced Binary Search Tree Given a binary tree, Find the Maximum Path Sum between Any Two Leaves Sort an Array According to the Order Defined by Another Array Sort an Array - odd numbers appear first in ascending order followed by the even numbers in descending order. Print Binary Tree Nodes in Zigzag Order: Spiral Traversal Pattern Find the first repeated element in an array by its index Check if One Binary Tree is a Subtree of Another In a Binary Tree, Create Linked Lists of all the nodes at each depth Level Order Traversal, Print each level in separate line Swap Every Kth Node in a LinkedList Remove Duplicates from an Unsorted Linked list String Compression using count of repeated characters - Run Length Encoding Replace Spaces with '%20' Without Using Default Functions Find Whether Two Strings are Permutation of each other 1 2 3 4 5