C program to multiply matrices - this program multiplies two matrices which will be entered by the user.
Solution:
/*C programme to multiply mattrix*/
#include <stdio.h>
int main()
{
int a[10][10], b[10][10], mult[10][10], r1, c1, r2, c2, i, j, k;
printf("Enter rows and column for first matrix: ");
scanf("%d%d", &r1, &c1);
printf("Enter rows and column for second matrix: ");
scanf("%d%d",&r2, &c2);
/* If colum of first matrix in not equal to row of second matrix, asking user to enter the size of matrix again. */
while (c1!=r2)
{
printf("Error! column of first matrix not equal to row of second.\n\n");
printf("Enter rows and column for first matrix: ");
scanf("%d%d", &r1, &c1);
printf("Enter rows and column for second matrix: ");
scanf("%d%d",&r2, &c2);
}
/* Storing elements of first matrix. */
printf("\nEnter elements of matrix 1:\n");
for(i=0; i<r1; ++i)
for(j=0; j<c1; ++j)
{
printf("Enter elements a%d%d: ",i+1,j+1);
scanf("%d",&a[i][j]);
}
/* Storing elements of second matrix. */
printf("\nEnter elements of matrix 2:\n");
for(i=0; i<r2; ++i)
for(j=0; j<c2; ++j)
{
printf("Enter elements b%d%d: ",i+1,j+1);
scanf("%d",&b[i][j]);
}
/* Initializing elements of matrix mult to 0.*/
for(i=0; i<r1; ++i)
for(j=0; j<c2; ++j)
{
mult[i][j]=0;
}
/* Multiplying matrix a and b and storing in array mult. */
for(i=0; i<r1; ++i)
for(j=0; j<c2; ++j)
for(k=0; k<c1; ++k)
{
mult[i][j]+=a[i][k]*b[k][j];
}
/* Displaying the multiplication of two matrix. */
printf("\nOutput Matrix:\n");
for(i=0; i<r1; ++i)
for(j=0; j<c2; ++j)
{
printf("%d ",mult[i][j]);
if(j==c2-1)
printf("\n\n");
}
return 0;
}