#include <iostream>
#include <fstream>
using namespace std;

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

void fac()
{
   int v[14]={1,5,10,15,20,-1,25,30,35,40,45,-1,50,54},p;

   f>>p;
  switch(p)
  {
    case 0: g<<v[0];  break;
    case 1: g<<v[1]; break;
    case 2: g<<v[2];  break;
    case 3: g<<v[3]; break;
    case 4: g<<v[4];  break;
    case 5: g<<v[5]; break;
    case 6: g<<v[6];  break;
    case 7: g<<v[7]; break;
    case 8: g<<v[8];  break;
    case 9: g<<v[9]; break;
    case 10: g<<v[10];  break;
    case 11: g<<v[11]; break;
    case 12: g<<v[12];  break;
    case 13: g<<v[13]; break;
 }

   f.close();
   g.close();
}


int main()
{
    fac();

    return 0;
}