#include<iostream>
#include<iomanip>
using namespace std;
int main(){
    string type;
    int discount;
    float months;
    cin>>type>>discount>>months;
    if((type!="Basic"&&type!="Standard"&&type!="Premium")||(discount<0||discount>1)||(months<=0||months>10))
        cout<<"Invalid input";
        return 0;
    }
    float cost=0;
    if(type=="Basic")cost=30;
    else if(type=="Standard")cost=50;
    else if(type=="Premium")cost=80;
    float total=cost*months;
    if(discount==1)total*=0.8;
    cout<<fixed<<setprecision(2)<<total;
    return 0;
}