#include <iostream>
#include <fstream>

using namespace std;

ifstream in("fact.in");
ofstream out("fact.out");

int main()
{

    int n,i,p,c,nr=0;
    in>>p;
    if(p==0)
        n=1;
    else if(p%5==1)
        n=5*p-5;
    else if(p%5==0)
        n=1;
    else
        n=5*p;
    out<<n;
    in.close();
    out.close();
    return 0;
}