#include<iostream>
#include<fstream>
using namespace std;
ifstream f("fact.in");
ofstream g("fact.out");
int main()
{int p=0,i=0,c=0;
 f>>p;
 for(i=5,c=0;c<p;i+=5)
 {if(i%25==0)
     c+=2;
  else
	 c+=1;
 }
 if(c==p)
    if(p!=0)
	   g<<i-5;
    else
	   g<<1;
 else
	g<<-1;
 return 0;
}