// program to multiply 2 matrices ( A and B or M by N of rows and columns defined by the user)
# include <stdio.h>
int main ()
{ int d,i,j,k,l,m,n,p,q,t,u,x ;
 
  int A[m] [n];
 int B[k] [l];
 int C[t] [u];
 
 i=0; d=0; j=0; j=0; k=0; l=0; m=0; n=0; n=0; p=0; q=0; t=0; u=0; x=0;
 
/* Entre the size of the matrices A and B */
 
printf (" Entre no. of rows for 1st matrix : \n");
scanf (" %d", &m );
printf (" Entre no. of rows for 1st matrix : \n");
scanf (" %d", &m );
printf (" Entre no. of rows for 2nd matrix : \n");
scanf (" %d", &p );
printf (" Entre no. of columns for 2nd matrix : \n");
scanf (" %d", &q );
 
/* Entre the values of the matrices */
 
printf (" Entre values for 1st matrix from 1st row,1st col integer to the right end then 2nd row, 1st col to the right end.... : \n");
 
   while ( i<m)
	     { while ( j<n)
			   { printf (" A[%d] [%d] = ? :" , i,j );
			     scanf ("%d", &A[i] [j] ); ++j; } j=0 ; ++i}
 
printf (" Entre values for 2nd matrix from 1st row,1st col integer to the right end then 2nd row, 1st col to the right end.... : \n");
 
 i=0;j=0
 
   while (i<p)
	     { while (j<q)
			   { printf (" B[%d] [%d] = ? :" , i,j );
			     scanf ("%d", &B[i] [j] ); ++j; } j=0 ; ++i}
 
	   i=0; j=0;
 
/* Calculate the product of matrix A and matrix B */
 
   while (k<p)
             { while ( i<m)
                         { while (j<n)
                                      { C[t] [u]+=A[i] [j]*B[k] [l] ;
                                        ++j ; ++k ; }
                                        ++i ; ++t ; k=0 ; j=0 ; }
                                        t=0 ; ++u ; i=0 ; j=0 ; ++l ; k=0 ; }
 
 
           t=0; u=0;
 
/* Read out the values of the obtained matrics C */
 
   while (t<x)
             { while (u<d)
                          { printf (" C[%d] [%d] = %d\t\t",t,u, C[t] [u]) ; }
                            printf ("\n") ;
                            ++u ; }
                            u=0 ; ++t ; }