Suppose we have a string str. We have to find the last non-repeating character in it. So if the input string is like “programming”. So the first non-repeating character is ‘n’. If no such character is present, then return -1.We can solve this by making one frequency array. This will ... Read More

Given two positive integers n and k, and we have to find the positive integer x, such that (x % k)*(x / k) is same as n. So if the n and k are 4 and 6 respectively, then the output will be 10. So (10 % 6) * (10 ... Read More

Suppose we have an array of digits. We have to find the maximum number that can be obtained using all digits of the array. So if the array is like [3, 3, 9, 6, 2, 5], then maximum number can be 965332.From the problem, we can see that we can ... Read More

Suppose we have an array of N distinct integers. We have to find the max element in an interval [L, R] such that the interval contains exactly one of the given N integers and 1

Suppose we have a 2D matrix with positive integers. We have to find the minimum steps required to move from to the end of the matrix (rightmost bottom cell), If we are at cell (i, j), we can go to the cell (i, j+mat[i, j]) or (i+mat[i, j], j), We ... Read More

Suppose we have a binary tree and a value K. The task is to print the Kth node in the vertical order traversal. If no such node exists, then return -1. So if the tree is like below −The vertical order traversal is like −4 2 1 5 6 3 ... Read More

Suppose we have some points, and one integer k. We have to find minimum radius of a circle whose center is at (0, 0) to cover k points. So if the points are like (1, 1), (-1, -1), (1, -1), and k = 3, then radius will be 2.Here we ... Read More

Suppose we have a number N. We have to find minimum number that divide N to make it perfect square. So if N = 50, then minimum number is 2, as 50 / 2 = 25, and 25 is a perfect square.A number is perfect square if it has even ... Read More

Suppose we have an array of n elements. We have to find the first, second and the third minimum elements in the array. First minimum is the minimum of the array, second min is minimum but larger than the first one, and similarly the third min is minimum but greater ... Read More

As we know that log(x*y) = log(x) + log(y). So we will see what are the minimum number of log values are required to calculate all log values from 1 to N. So if N is 6, then output will be 3, as from log(1) to log(6), there are three ... Read More