#include<iostream>
#include<vector>
#include<algorithm>
#include<cmath>
#include<string>

using namespace std;

int main(){
	long long  n;
	cin >> n;
	long long mod = 1000000000000LL;

	long long sum=1;
	for(int i=n; i>0; i--){
		sum *= i;
		sum = sum % mod;
	}
	cout << sum<<endl;
}