#include<bits/stdc++.h>
using namespace std;
#define int long long
const int mod = 1e9 + 1;

int fact(int n){
	if(n == 0){
		return 1;
	}else{
		return ((n % mod) * fact(n - 1)) % mod;
	}
}

signed main(){
	int n;
	cin >> n;
	cout << fact(n) << endl;
}