Matrix Multiplication in C Language

In this C program we will multiply two matrices and print the result on the screen.The elements of the matrices will be taken from the user.

input:

The elements of matrices.

output:

The Multiplication of the two matrices.

CODE---->

#include <stdio.h>
void input(int first[10][10],int second[10][10],int r1,int c1,int r2,int c2)
{
 int i,j;
    printf("\nEnter elements of matrix 1:\n");
    for (i=0;i<r1;i++)
 {
     for (j=0;j<c1;j++)
  {
            printf("Enter data: ");
            scanf("%d",&first[i][j]);
        }
    }
    printf("\nEnter elements of matrix 2:\n");
    for(i=0;i<r2;i++)
 {
        for(j=0;j<c2;j++)
  {
            printf("Enter data: ");
            scanf("%d",&second[i][j]);
        }
    }
}
void multiply(int first[10][10],int second[10][10],int mul[10][10],int r1,int c1,int r2,int c2)
{
 int i,j,k;
    // Initializing elements of matrix mul to 0.
    for(i=0;i<r1;i++)
 {
        for(j=0;j<c2;j++)
  {
            mul[i][j]=0;
        }
    }
    // Multiplying first and second matrices and storing in mul.
    for(i=0;i<r1;i++)
 {
        for(j=0;j<c2;j++)
  {
            for(k=0;k<c1;k++)
   {
                mul[i][j]=mul[i][j]+first[i][k]*second[k][j];
            }
        }
    }
}
void display(int mul[10][10],int r1,int c2)
{
 int i,j;
    printf("\nOutput Matrix:\n");
    for(i=0;i<r1;i++)
 {
        for(j=0;j<c2;j++)
  {
            printf("%d  ",mul[i][j]);
            if(j==c2-1)
                printf("\n");
        }
    }
}
int main()
{
    int first[10][10],second[10][10],mul[10][10],r1,c1,r2,c2;
    printf("Enter No. of rows and column for the first matrix: ");
    scanf("%d%d",&r1,&c1);
    printf("Enter No. of rows and column for the second matrix: ");
    scanf("%d%d",&r2,&c2);
    // Taking input until columns of the first matrix is equal to the rows of the second matrix
    while(c1!=r2)
 {
        printf("\nError! Enter rows and columns again.\n");
        printf("Enter rows and columns for the first matrix: ");
        scanf("%d%d",&r1,&c1);
        printf("Enter rows and columns for the second matrix: ");
        scanf("%d%d",&r2,&c2);
    }
    // Function to take matrices data
    input(first,second,r1,c1,r2,c2);
    // Function to multiply two matrices.
    multiply(first,second,mul,r1,c1,r2,c2);
    // Function to display resultant matrix after multiplication.
    display(mul,r1,c2);
    return 0;
}

Download the C-Program file of this Program.

Don't just read, run on your pc !!!

RESULT :

Enter No. of rows and column for the first matrix: 2
2
Enter No. of rows and column for the second matrix: 2
2

Enter elements of matrix 1:
Enter data: 2
Enter data: 1
Enter data: 3
Enter data: 4

Enter elements of matrix 2:
Enter data: 1
Enter data: -2
Enter data: -1
Enter data: 1

Output Matrix:
1  -3
-1  -2

--------------------------------
Process exited after 18.96 seconds with return value 0
Press any key to continue . . .

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