#include <cstdio>
#include <iostream>
using namespace std;
typedef long long ll;
const ll mod = 1000000000000;
int main() {
  ll N;
  cin >> N;
  if(N>=50) {
    printf("000000000000\n");
  } else {
    ll ans=1;
    for (ll i=2;i<=N;i+=1){
      ans = ans * i;
    }
    printf("%llu\n", ans % mod);
  }
}