void silnia(int n) {
    long long int b = 1;
    cout << "\nn" << "        " << "n!" << endl;
    for(int i=0; i<=n; i++) {
        if(i==0) b = 1;
        else b *= i;
        cout << i;
        if(i<10) cout << " ";
        cout << "       " << b << endl;
    }
    cout << "\nSilnia z n = " << n << " wynosi: " << b << "\n\n";
}