#include <iostream>
using namespace std;

int n,ans[11] = {0,1,2,6,24,120,720,5040,40320,362880,3628800};

int main(){
	cin>>n;
	cout<<ans[n];
}
/**************************************************************
	Problem: 1004
	User: long
	Language: C++
	Result: Accepted
	Time:8 ms
	Memory:2072 kb
****************************************************************/