#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);
	for(int i=0; i<2; i++){
		for(int j=0; j<2; j++){
			printf("%d ",ans[i][j]);
		}
	}
 
	return 0;
}
 

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