Problem Statement In this problem, we are given two strings ‘s’ & ‘t’ consisting of lower-case English characters. In one operation, we can choose any character in string ‘t’ and change it to some other character. We need to find the minimum number of such operations to make ‘t’ an …
Problem Statement In the problem “License Key Formatting”, the input consists of a string of characters, representing a license key. Initially, the string is separated into N + 1 groups(words) by N dashes in between. We are also given an integer K, and the goal is to format the string …
Problem Statement In this problem, we are given a string of characters, containing only ‘R’ and ‘L’. We call a string balanced if it has the same number of ‘R’s and ‘L’s. We can split the given string into disjoint substrings. The goal is to find the maximum possible number …
Problem Statement In this problem, we have to design a class KthLargest() that initially has an integer k and an array of integers. We need to write a parameterized constructor for it when an integer k and array nums are passed as arguments. The class also has a function add(val) that adds …
Problem Statement In this problem, we are given an array of integer and array of arrays queries. For the ith query, we will have two parameters, index and val. After each query, we add val to array[index]. We need to find the sum of all even integers in the array after …
Problem Statement In this problem, we are given a linked list with its nodes having integer values. We need to delete some nodes from the list which have value equal to val. The problem does not require to be solved in-place but we will discuss one such approach. Example List = …
Problem Statement In this problem, we are given a decimal number. The goal is to find its complement. Example N = 15 0 N = 5 2 Approach (Flipping bit by bit) We can flip every bit in the integer ‘N’ to get its complement. The important part is, we …
Problem Statement In this problem, we are given an array of integers. Also, we are allowed to perform a certain set of operations on this array. In one operation, we can increment ” n – 1″ (all elements except any one) elements in the array by 1. We need to …
Problem Statement In this problem, we are given two strings, a and b. Our goal is to tell whether the two strings are isomorphic or not. Two strings are called isomorphic if and only if the characters in the first string can be replaced by any character(including itself) at all …
Problem Statement In this problem, we are given a grid in form of a 2-D array. grid[i][j] = 0 represents there is water at that point and grid[i][j] = 1 represents land. Grid cells are connected vertically/horizontally but not diagonally. There is exactly one island (a connected component of land …