#include <iostream>
#include <string>
using namespace std;
int main(){
    int type;
    string driver,passenger,route,distStr;
    double dist;
    cin>>type;
    cin.ignore();
    getline(cin,driver);
    getline(cin,passenger);
    getline(cin,route);
    getline(cin,distStr);
    dist=stod(distStr);
    if(type==1) cout<<dist*1.5;
    else if(type==2)cput<<dist*0.8;
    else cout<<"Invalid input";
}