#include <iostream>
#include <cstdio>
#define int long long
#define MOD 1000000000000
using namespace std;

signed main(){
	int n,res = 1;
	bool flag = false;
	cin >> n;
	for(int i = 2;i <= n;i++){
		if(!res) break;
		res *= i;
		if(res >= MOD){
			flag = true;
			res %= MOD;
		}
	}
	if(flag) printf("%012lld\n",res);
	else cout << res << endl;
	return 0;
}