C program to add and multiply two compatible matrices

In this article we will learn to implement a C program to add and multiply two compatible matrices. A C program is provided below to read two matrices, add them and then multiply them.

Program is as follows:

//C program to add and multiply two compatible matrices
#include<stdio.h>
#include<conio.h>
void main()
{
	int a[3][3], b[3][3], c[3][3]={0}, d[3][3]={0};
	int i,j,k,m,n,p,q;
	printf("Enter no. of rows and columns in matrix A: ");
	scanf("%d%d",&m,&n);
	printf("Enter no. of rows and columns in matrix B: ");
	scanf("%d%d",&p,&q);
	if(m!=p || n!=q)
	{
		printf("Matrix Addition is not possible");
		return;
	}
	else if(n!=p)
	{
		printf("Matrix Multiplication is not possible");
		return;
	}
	else
	{
		printf("Enter elements of matrix A: ");
		for(i=0;i<m;i++)
			for(j=0;j<n;j++)
				scanf("%d", &a[i][j]);
		printf("Enter elements of matrix B: ");
		for(i=0;i<p;i++)
			for(j=0;j<q;j++)
				scanf("%d", &b[i][j]);
		//Matrix Addition
		for(i=0;i<m;i++)
			for(j=0;j<n;j++)
				c[i][j] = a[i][j] + b[i][j];
		printf("\nResult of Matirx Addition:\n");
		for(i=0;i<m;i++)
		{
			for(j=0;j<n;j++)
				printf("%d ", c[i][j]);
			printf("\n");
		}
		//Matrix Multiplication
		for(i=0;i<m;i++)
			for(j=0;j<q;j++)
				for(k=0;k<p;k++)
					d[i][j] += a[i][k]*b[k][j];
		printf("\nResult of Matirx Multiplication:\n");
		for(i=0;i<m;i++)
		{
			for(j=0;j<q;j++)
				printf("%d ", d[i][j]);
			printf("\n");
		}
	}
	getch();
}

Input and output for the above program is as follows:

Enter no. of rows and columns in matrix A: 3 3
Enter no. of rows and columns in matrix B: 3 3
Enter elements of matrix A:
1 1 1
2 2 2
3 3 3
Enter elements of matrix B:
2 2 2
2 2 2
2 2 2

Result of Matirx Addition:
3 3 3
4 4 4
5 5 5

Result of Matirx Multiplication:
6 6 6
12 12 12
18 18 18

Suryateja Pericherla

Suryateja Pericherla, at present is a Research Scholar (full-time Ph.D.) in the Dept. of Computer Science & Systems Engineering at Andhra University, Visakhapatnam. Previously worked as an Associate Professor in the Dept. of CSE at Vishnu Institute of Technology, India.

He has 11+ years of teaching experience and is an individual researcher whose research interests are Cloud Computing, Internet of Things, Computer Security, Network Security and Blockchain.

He is a member of professional societies like IEEE, ACM, CSI and ISCA. He published several research papers which are indexed by SCIE, WoS, Scopus, Springer and others.