// editor1
#include<iostream>
#include<iomanip>
using namespace std;
class membership
{
    public:
    string ethic;
    int discount;
    float duration;
    void getData()
    {
        cin>>ethic;
        cin>>discount;
        cin>>duration;
    }
void calculate()if{
        float costpermonth=0.0;
         if(ethic=="Basic")
        costpermonth=30.0;
        else if(ethic=="Standard")
        costpermonth=50.0;
        else if(ethic=="premium")
        costpermonth=80.0;
    else
    {
        cout<<"Invalid input";
        return;
    }
    if(discount<0||discount>1||duration<=0||duration>10)
    {
        cout<<"Invalid input";
        return;
    }
    float total=costpermonth*duration;
    if(discount==1)
    total=total*0.8;
    cout<<fixed<<setprecision(2)<<total;
}
};
int main()
{
  membership m;
  m.getData();
  m.calculate();
  return 0;
}