#include<fstream>
using namespace std;
int main()
{ int n=0,p;
ifstream in("fact.in");
ofstream out("fact.out");
in>>p;
if(p==0)
{out<<1<<endl;
}
while(p>0)
{
	if(p>=5)
	{n=n+25;
	p=p-6;
	}
	else
	{n=n+5;
	p--;
	}
}
out<<n<<endl;
in.close();
out.close();
return 0;
}