How to multiply two matrix using C, any sample program would be help?

Question

Input

520 * 12

Output

 1040
 520
 ----
 6240

Answer 1

/* C program to multiply the two matrices */

#include <stdio.h>
#include<conio.h> 
void main()
{
   int m, n, p, q, c, d, k, sum = 0;
   int ar1[10][10], ar2[10][10], mul[10][10];

   printf("Enter the number of rows and columns of first matrix\n");
   scanf("%d%d", &m, &n);
   printf("Enter the elements of first matrix\n");

   for (  c = 0 ; c < m ; c++ )
   {
       for ( d = 0 ; d < n ; d++ )
       {
           scanf("%d", &ar1[c][d]);
       }
   }

   printf("Enter the number of rows and columns of second matrix\n");
   scanf("%d%d", &p, &q);

   if ( n != p )
   {
      printf("Multiplication is not possible of the two matrices \n");
   }
   else
   {
      printf("Enter the elements of second matrix\n");

      for ( c = 0 ; c < p ; c++ )
      {
         for ( d = 0 ; d < q ; d++ )
         {
            scanf("%d", &ar2[c][d]);
         }
      }

      for ( c = 0 ; c < m ; c++ )
      {
         for ( d = 0 ; d < q ; d++ )
         {
            for ( k = 0 ; k < p ; k++ )
            {
               sum = sum + ar1[c][k]*ar2[k][d];
            }

            mul[c][d] = sum;
            sum = 0;
         }
      }

      printf("Product of entered matrices:-\n");

      for ( c = 0 ; c < m ; c++ )
      {
         for ( d = 0 ; d < q ; d++ )
            printf("%d\t", mul[c][d]);

         printf("\n");
      }
   }
   getch();
}

Output –

Enter the number of rows and columns of first matrix – 2 2
Enter the elements of first matrix –

2 3
4 3

Enter the number of rows and columns of second matrix – 2 3

5 7 2
5 6 4

Product of entered matrices is –

25 32 16
35 46 20