#include <stdio.h>

void array_mul(int (*x)[2], int (*y)[2], int (*ans)[2]) {
    for (int i = 0; i < 2; i++) {    
        for (int j = 0; j < 2; j++) { 
            ans[i][j] = 0;
            for (int k = 0; k < 2; k++) {
                ans[i][j] += x[i][k] * y[k][j];
            }
        }
    }
}

int main(void) {
    int x[2][2] = {{1, 2}, {3, 4}};
    int y[2][2] = {{1, 2}, {3, 4}};
    int ans[2][2];

    array_mul(x, y, ans);

    printf("Result:\n");
    for (int i = 0; i < 2; i++) {
        printf("%d %d\n", ans[i][0], ans[i][1]);
    }

    return 0;
}