include <iostream>
using namespace std;
int main()
{
int a,b,c;
cin >> a >> b >> c;
cout << (5*a*c+3*(c-d)(b-c)/a*b);}
include <iostream>
using namespace std;
int main()
{
int a,b,c;
cin >> a >> b >> c;
cout << (5*a*c+3*(c-d)(b-c)/a*b);
}