L1-048 矩阵A乘以B 分数 15

// 10'42"
#include <iostream>
using namespace std;
const int N = 110;
int arr[N][N];
int brr[N][N];
int crr[N][N];
int main()
{
    int x1, y1;
    cin >> x1 >> y1;
    for(int i = 1; i <= x1; ++ i)
        for(int j = 1; j <= y1; ++ j)
            cin >> arr[i][j];
    int x2, y2;
    cin >> x2 >> y2;
    if(y1 != x2)
    {
        cout << "Error: "<< y1 << " != " << x2 << endl;
        return 0;
    }
    for(int i = 1; i <= x2; ++ i)
        for(int j = 1; j <= y2; ++ j)
            cin >> brr[i][j];

    int x3 = x1, y3 = y2;
    for(int i = 1; i <= x3; ++ i)
        for(int j = 1; j <= y3; ++ j)
            for(int k = 1; k <= x2; ++ k)
                crr[i][j] += arr[i][k] * brr[k][j];
    cout << x3 << " " << y3 << endl;
    for(int i = 1; i <= x3; ++ i)
    {
        for(int j = 1; j <= y3; ++ j)
        {
        	cout << crr[i][j];
        	if(j != y3) cout << " ";
		}
		if(i != x3) cout << endl;
	}
    return 0;
}