#include <iostream>
using namespace std;

int main(){
	long long n, ans = 1;
	cin >> n;
	if(1230000000 <= n){
		cout << 0 << endl;
		return 0;
	}
	for(long long i = 1; i <= n; i++) (ans *= i) %= 1000000000000;
	cout << ans << endl;
}