#include <iostream>
#include <fstream>
using namespace std;
ifstream f("fact.in");
ofstream g("fact.out");
int p, n, x, c, i, s;
int main()
{
    f>>p;
    if(p<=4)
        g<<1;
    else
    {
        while(i<=p)
        {
            if(n==5)
                i++;
            n=n+5;
            i++;
        }
        g<<n;
    }
    return 0;
}