#include <iostream>
#include <iomanip>
#include <string>
using namespace std;
class Gym
{
    private:
    string type;
    int discountstatus;
    float duration;
    public:
    Gym(string t,int d,float m)
    {
        type=t;
        discountstatus=d;
        duration=m;
    }
    void Total()
    {
        float costpermonth;
        if (type!="Basic"&&type!="Standard"&&type!="Premium")
        {
            cout<<"Invalid input";
            return;
        }
        if (duration<0)
        {
            cout<<"Invalid input";
            return;
        }
        if (type=="Basic")
        {
            costpermonth=30;
        }
        else if(type=="Standard")
        {
            costpermonth=50;
        }
        else
        {
            costpermonth=80;
        }
        float total=costpermonth*duration;
        if (discountstatus==1)
        {
            total=total*0.8;
        }
        cout<<fixed<<setprecision(2)<<total;
    }
};
int main()
{
    string type;
    int discount;
    float months;
    cin>>type;
    cin>>discount;
    cin>>months;
    Gym member(type,discount,months);
    member.Total;
    return 0;
}