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Java program to check sparse matrix

In this java program, we are going to read a matrix and check whether it is sparse matrix or not?
Submitted by IncludeHelp, on November 02, 2017

Given a matrix and we have to check whether it is sparse matrix or not using java program.

Sparse Matrix

A matrix in which most of the elements are '0' then it is said to be a sparse matrix. Sparse matrices are used in specific ways in computer science and have different storage and techniques related to their use.

Example-1

Input Matrix 
1 1 1
0 0 0 
1 1 1

Output: It’s not a sparse matrix

Example-2

Input Matrix 
1 0 0 1
0 1 0 1
0 1 0 1
0 0 0 1

Output: It’s a sparse matrix 

Program to check sparse matrix in Java

import java.util.Scanner;

public class MatrixSparse 
{
	public static void main(String args[])
	{
		//scanner class object creation
		Scanner sc = new Scanner(System.in);
		
		//input numbers of rows and cols
		System.out.print("Enter the dimensions of the matrix : ");
		int m = sc.nextInt();
		int n = sc.nextInt();
		
		//declare two_d array (matrix) object
		double[][] mat = new double[m][n];
		
		//variable to store zero count
		//initializing it with 0
		int zeros = 0;
		
		//input matrix 
		System.out.println("Enter the elements of the matrix : ");
		for(int i=0; i<m; i++)
		{
			for(int j=0; j<n; j++)
			{
				mat[i][j] = sc.nextDouble();
				if(mat[i][j] == 0)
				{
					//counting zeros
					zeros++;
				}
			}
		}

		//check condiion
		if(zeros > (m*n)/2)
		{
			System.out.println("The matrix is a sparse matrix");
		}
		else
		{
			System.out.println("The matrix is not a sparse matrix");
		}

		sc.close();
	}
}

Output 1

Enter the dimensions of the matrix : 3 3
Enter the elements of the matrix : 
1 1 1
0 0 0 
1 1 1
The matrix is not a sparse matrix

Output 2

Enter the dimensions of the matrix : 4 4
Enter the elements of the matrix : 
1 0 0 1
0 1 0 1
0 1 0 1
0 0 0 1
The matrix is a sparse matrix