# Status Problem video Level Completes Likes 239 Find local minimum or local maximum in O(1). Medium % 0 223 Stock Single Sell Problem - O(n) Solution Hard % 2 221 Maximum difference between two elements where larger element appears after the smaller element Medium % 0 195 Single Threaded Binary Tree Complete Implementation Hard % 0 164 Print All Possible Subsets with Sum equal to a given Number Hard % 0 161 The Word Break Problem Hard % 0 159 Backtracking - Knight's Tour Problem Hard % 0 158 Backtracking - Search a Word In a Matrix Hard % 0 157 Backtracking - N Queens Problem - Better Solution Hard % 0 156 Backtracking - N Queens Problem Hard % 0 149 Backtracking - Rat In A Maze Puzzle Hard % 0 146 Dynamic Programming - Stairs Climbing Puzzle Beginner % 1 145 Dynamic Programming - Minimum Coin Change Problem Medium % 1 143 Merge K Sorted Arrays Hard % 0 134 Diameter Of a Binary Tree Hard % 1 131 Find the Height of a tree without using Recursion Medium % 0 121 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 % 0 116 Print All Possible Valid Combinations Of Parenthesis of Given 'N' Medium % 1 108 Implement Queue Using Stacks Medium % 0 102 Merge Sort in a Linked list Medium % 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 89 In an Array, find the Smallest Subarray with Sum Greater than the Given Value Medium % 0 84 Find All Elements in an Array which appears more than N/K times, N is Array Size and k is a Number. Hard % 0 82 Print All The Nodes Which are X distance from the Given Node Hard % 0 45 Print a path from Root to Node in Binary Tree 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 36 Find the Maximum Depth OR Height of a Binary Tree Beginner % 1 Find local minimum or local maximum in O(1). Stock Single Sell Problem - O(n) Solution Maximum difference between two elements where larger element appears after the smaller element Single Threaded Binary Tree Complete Implementation Print All Possible Subsets with Sum equal to a given Number The Word Break Problem Backtracking - Knight's Tour Problem Backtracking - Search a Word In a Matrix Backtracking - N Queens Problem - Better Solution Backtracking - N Queens Problem Backtracking - Rat In A Maze Puzzle Dynamic Programming - Stairs Climbing Puzzle Dynamic Programming - Minimum Coin Change Problem Merge K Sorted Arrays Diameter Of a Binary Tree Find the Height of a tree without using Recursion Print All the Subsets of a Given Set (Power Set) Print All Combinations of subset of size K from Given Array Print All Possible Valid Combinations Of Parenthesis of Given 'N' Implement Queue Using Stacks Merge Sort in a Linked list Construct Binary Search Tree from a given Preorder Traversal Using Stack (Without Recursion) Construct Binary Search Tree from a given Preorder Traversal using Recursion In an Array, find the Smallest Subarray with Sum Greater than the Given Value Find All Elements in an Array which appears more than N/K times, N is Array Size and k is a Number. Print All The Nodes Which are X distance from the Given Node Print a path from Root to Node in Binary Tree In a Binary Tree, Create Linked Lists of all the nodes at each depth. Level Order Traversal, Print each level in separate line. Find the Maximum Depth OR Height of a Binary Tree 1 2