#include <bits/stdc++.h>
using namespace std;
typedef long long ll;

ll MOD = 1e12;

ll fact(int n) {
    if (n == 1) return 1;
    else return ( n * fact(n-1) ) % MOD;
}

int main(void) {
    int N;
    cin >> N;
    cout << fact(N) << endl;
    return 0;
}