#include<iostream>
#include<string>
#include<iomanip>
using namespace std;
int main()
{
    string membershipType;
    int discountStatus;
    float duration;
    cin>>membershipType>>discountStatus>>duration;
    if((membershipType!="Basic" && membershipType !="Standard" && membershipType!="Premium")|| (discountStatus<0||discount>1)||(dur
    {
        cout<<"Invalid input"<<endl;
        return 0;
    }
    float monthlyCost;
    if(membershipType=="Basic")
        monthlyCost=30.0;
    else if
    (membershipType=="Standard")
        monthlyCost=50.0;
    else 
        monthlyCost=80.0;
        float total=monthlyCost * duration;
         total *=0.8;
        cout<<fixed<<setprecision(2)<<total<<endl;
    
    return 0;
}