#include <stdio.h>
 
void array_mul( int (*x)[2], int (*y)[2], int (*ans)[2]);
 
int main(void) 
{
	int x[2][2] = { {1,2}, {3,4} };
	int y[2][2] = { {1,2}, {3,4} };
	int ans[2][2] = { { 0 } };
 
	array_mul( x, y, ans );
 
	return 0;
}
 
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]S*y[k][j];
			}
			printf("%d ", ans[i][j]);
		}
		putchar('\n');
	}
}

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