#include <cstdio>
using ll = long long;
using namespace std;
int main() {
    ll n; scanf("%lld", &n);
    constexpr ll mod = 1e12;
    ll fact = 1;
    for (ll i = 0; fact and i < n; ++ i) {
        fact = fact * (i+1) % mod;
    }
    if (fact) {
        printf("%lld\n", fact);
    } else {
        printf("000000000000\n");
    }
    return 0;
}