#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);
	for(int i=0;i<2;i++){
		for(int j=0;j<2;j++){
			printf("%d ",ans[i][j]);
		}
		printf("\n");
	}
	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++){
			for(int k=0;k<2;k++){
				ans[i][j]=x[i][k]*y[k][j]+ans[i][j];
 
			}
		}
	}
}

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