#include <bits/stdc++.h>
using namespace std;
 
#define fi first
#define se second
#define pb push_back
using vi = vector <int>;
using ll = long long;
using pii = pair <int, int>;
//~ const ll mod = 998244353;
const ll mod = 1e9 + 7;
ll qpow(ll a, ll b, ll m = mod) { ll r = 1, t = a;
	for(; b; b /= 2) { if(b & 1) r = r * t % m; t = t * t % m; } return r; }

int main() {
	ios :: sync_with_stdio(false);
	
	ll n; cin >> n;
	ll mod = 1e12;
	
	bool pre = 0;
	ll x = 1;
	for(ll i = 1; i <= n; i ++) {
		x = x * i;
		if(x >= mod) {
			pre = 1;
			x %= mod;
		}
		
		if(x == 0) break;
	}
	
	if(pre) {
		string s = to_string(x);
		while(s.size() < 12) s = '0' + s;
		cout << s << '\n';
	} else
		cout << x << '\n';
}