#include <stdio.h>
void array_mul(int (*x)[2], int (*y)[2], int (*ans)[2]);
 
int main() {
    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("計算結果:\n");
    for(int i=0;i<2;i++){
        for(int j=0;j<2;j++) {
            printf("%4d",ans[i][j]);
        }
        printf("\n");
    }
    return 0;
}
 
void array_mul(int (*x)[2], int (*y)[2], int (*ans)[2]){
    int i,j,k;
    for(i=0;i<2;i++) {
        for(j=0;j<2;j++){
        	ans[i][j]=0;
            for(k=0;k<2;k++){
                ans[i][j] += x[i][k] * y[k][j];
            }
        }
    }
}

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