#include <stdio.h>
#include <stdlib.h>

int main()
{
    int a1,a2,b1,b2,i,j;
    printf("enter size of arrays ::n");
    scanf("%d%d%d%d",&a1,&a2,&b1,&b2);
    while(a2!=b1) // condition of matrices multiplication//
    {
        printf("enter suitable dimensions!!n");
        scanf("%d%d%d%d",&a1,&a2,&b1,&b2);
    }
    int A[a1][a2];
    int B[b1][b2];
    int C[a1][b2];
    // input elements of array//
    printf("enter elements of first array row by row ::n");
    for(i=0; i<a1; i++)
    {
        for(j=0; j<a2; j++)
        {
            scanf("%d",&A[a1][a2]);
        }
        printf("n");
    }
    printf("enter elements of second array row by row ::n");
    for(i=0; i<b1; i++)
    {
        for(j=0; j<b2; j++)
        {
            scanf("%d",&
                  B[b1][b2]);
        }
        printf("n");
    }
    // three counters to iterate through three matrices //
    int element=0,k=0;
    for (i=0; i<a1; i++)
    {
        for (j=0; j<b2; j++)
        {
            while(k<b1)
            {
                element+=(A[i][k]*B[k][j]);
                k++;

            }

            C[i][j]=element;
            element=0;
            k=0;
        }

    }
    printf("the product matrix is ::");
    for(i=0; i<a1; i++)
    {
        for(j=0; j<b2; j++)
        {
            printf("%d  ",C[i][j]);
        }

    }

    return 0;
}