In Reorganize String problem we have given a string containing some characters “a-z” only. Our task is to rearrange those characters such that no two same characters are adjacent to each other. Example Input apple Output pelpa Input book Output obko Input aa Output not possible Input aaab Output not …
Duplicate Subtrees Subtrees are said to be duplicate if they have the same node values and structure. Given a binary tree with n nodes. Find all the duplicate subtrees and return their root node. Example Here, the subtrees 4 and 2->4 appear more than once therefore we will return root …
In the String Compression problem, we have given an array a[ ] of type char. Compress it as the character and count of a particular character (if the count of character is 1 then the only character is stored in a compressed array). The length of the compressed array should …
Problem Description of Queue Reconstruction by Height Suppose you have a random list of people standing in a queue. Each person is described by a pair of integers (h, k), where h is the height of the person and k is the number of people in front of this person …
Let’s understand Find Peak Element problem. Today we have with us an array that needs its peak element. Now, you must be wondering as to what do I mean by the peak element? The peak element is one which is greater than all its neighbours. Example: Given an array of …
In K-th Smallest Element in a Sorted Matrix problem, we have given an n x n matrix, where every row and column is sorted in non-decreasing order. Find the kth smallest element in the given 2D array. Example Input 1: k = 3 and matrix = 11, 21, 31, 41 …
In the Minimum Height Trees problem, we have given an undirected graph which is tree in nature (acyclic and fully connected graph). Find out those vertices (or vertex) in the graph that when taken as root, will give tree with minimum height. Height of Tree: Height of the tree rooted …
Problem In the Valid Triangle Number problem, we have given an array of non-negative integers. Find the number of triplets that can form a triangle. If we consider the numbers in the array as side lengths of the triangle. Example Input [ 2, 2, 3, 4 ] Output 3 Explanation We …
Problem Given a linked list. The elements of the linked list are in increasing order. Convert the given linked list into a highly balanced binary search tree. A highly balanced binary search tree is a binary search tree in which the difference between the depth of two subtrees of any …