Test

#include <iostream>

using namespace std;

typedef long long ll;
typedef unsigned long long ull;
typedef double dl;

dl Factorial(ll n) {
    if (n - 1) {
        return (n * Factorial(n - 1));
    }
    else {
        return 1;
    }
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    ll x;
    cin >> x;
    ll ans;
    ans = Factorial(x);
    cout << ans;
    return 0;
}