#include<iostream>
using namespace std;
long long n,count = 1;
int main(){
	cin>>n;
	for(long long i = 1;i <= n;i++){
		count *= i;
		count /= 10000000;
	}
	while(count / 10 % 10 == 0){
		count /= 10;
	}
	cout<<count / 10 % 10;
	return 0;
}