matrix multiplication

#include <iostream>

using namespace std;

int main()
{
    int n, m;
    cin >> n >> m;

    // prvata matrica
    int a[n][m] = {};

    for (int i = 0; i < n; i++) {
        for (int j = 0; j < m; j++) {
            cin >> a[i][j];
        }
    }

    int c, d;
    cin >> c >> d;

    // vtorata matrica
    int b[c][d] = {};

    for (int i = 0; i < c; i++) {
        for (int j = 0; j < d; j++) {
            cin >> b[i][j];
        }
    }

    // p = a*b
    int p[n][d] = {};

    for (int i = 0; i < n; i++) {
        for (int j = 0; j < d; j++) {
            for (int s = 0; s < m; s++) {
                p[i][j] += a[i][s] * b[s][j];
            }
        }
    }

    // pechati p
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < d; j++) {
            cout << p[i][j] << " ";
        }
        cout << endl;
    }

    return 0;
}