P37390: Producte de matrius quadrades

#include <iostream>
#include <vector>
using namespace std;

typedef vector<int> Columna;
typedef vector<Columna> Matriu;

Matriu producte(const Matriu& a, Matriu& b) {
    int tam = a.size();
    Matriu Producte(tam, Columna(tam));
    for (int i = 0; i < tam; ++i) {
        for (int j = 0; j < tam; ++j) {
            int aux = 0;
            for (int k = 0; k < tam; ++k) {
                aux += a[i][k] * b[k][j];
            }
            Producte[i][j] = aux;
        }
    }
    return Producte;
}

int main() {
    int f, c;
    cin >> f >> c;
    Matriu a(f, Columna(c));
    Matriu b(f, Columna(c));
    for (int i = 0; i < f; ++i) {
        for (int j = 0; j < c; ++j) {
            cin >> a[i][j];
        }
    }
    for (int i = 0; i < f; ++i) {
        for (int j = 0; j < c; ++j) {
            cin >> b[i][j];
        }
    }
    for (int i = 0; i < f; ++i) {
        for (int j = 0; j < c; ++j) {
            cout << producte(a, b)[i][j] << " ";
        }
        cout << endl;
    }
}