#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define llong long long

int main() {
    llong n;
    cin >> n;

    llong result = 1;
    const llong DIVISOR = 10e11;
    bool overed = false;
    for(int i=1; i<=n; i++) {
        result *= i;
        overed |= result > DIVISOR;
        result %= DIVISOR;
        if(result == 0) break;
    }
    if(overed) {
        printf("%11ld\n", result);
    } else {
        cout << result << endl;
    }
}