#include <fstream>
using namespace std;
int p;
void citire ()
{
    ifstream in ("fact.in");
    in >> p;
    in.close ();
}
void afis (long long n)
{
    ofstream out ("fact.out");
    out << n;
    out.close ();
}
void solve ()
{
    if (p == 0)
        afis (1);
    else
        if (p < 5)
            afis (p * 5);
        else
            if (p == 5)
                afis (-1);
            else
                afis ((p * 4) + (p - 5));
}
int main()
{
    citire ();
    solve ();
    return 0;
}