#include<iostream>
using namespace std;
int main()
{
    string v;
    double k;
    double h;
    cin>>v;
    cin>>k;
    cin>>h;
    if(v==Bike||v==Car)
    {
    if(k<0||h<0)
    {
        cout<<"invalid input";
    }
    else
    {
        if(v=="Car")
        {
            cout<<k/h;
        }
        else if(v=="Bike")
        {
            cout<<k*h;
        }
        else
        {
            cout<<"invalid input";
        }
    }
    }
    else
    {
        cout<<"invalid input";
    }
    return 0;
}