Matrix Program

Rotate Matrix By 90 Degree

Problem description: Given an N X N integer matrix, rotate it bye 90 degrees in place.In-place means minimal extra memory to be used, i.e. don’t make a new array to copy into). Rotate clockwise means top-row becomes right-column, right column becomes bottom-row etc. eg. Solution: The idea is to do a “four-way” swap variable, we Read More →

Set every cell in matrix to 0 if that row or column contains a 0

Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place. This problem should be solved in place, i.e., no other array should be used. We can use the first column and the first row to track if a row/column should be set Read More →

Maximum size square sub-matrix with all 1s

Problem: Given a binary matrix consisting only 0s and 1s, find the maximum size square sub-matrix with all 1s. Example: Consider the below matrix. 0 1 1 0 1 1 1 0 1 0 0 1 1 1 0 1 1 1 1 0 1 1 1 1 1 0 0 0 0 0 The Read More →

Boolean Matrix Question

Given a matrix of size n x m filled with 0′s and 1′s e.g.: 1 1 0 1 0 0 0 0 0 0 0 1 0 0 0 1 0 1 1 0 if the matrix has 1 at (i,j), fill the column j and row i with 1′s i.e., we get: 1 1 Read More →

Find row with maximum number of 1s in sorted matrix

Problem: You are given a MxN matrix with each row sorted. Matrix is having only 0′s and 1′s. You have to find row wotth maximum number of 1′s. eg. matrix given: 000111 001111 011111 000011 111111 // row with max number of 1′s Method 1: Brute force approach Traverse the matrix row wise and count Read More →

Search in a row wise and column wise sorted matrix

You are given an 2D array of MxN which is row and column wise sorted. What is the efficient way to search for an element? Steps: 1) Start from top right element 2) for loop compare this element e with x a) if they are equal then return its position b) e < x then Read More →

Print a Square Matrix in Spiral Form


Given a N*N square matrix. Write a code to print it in spiral order. Time Complexity : O(N^2)