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