TransportPrice

import java.util.Scanner;

public class Transport {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        int km = Integer.parseInt(sc.nextLine());
        String tarifa = sc.nextLine();

        double taxi =0;
        double price =0;

        if (tarifa.equals("day")){
            taxi = 0.79;
        } else taxi = 0.90;

        if (km < 20) {
            price = 0.70+(km * taxi);
        } else if (km<100){
            price = km*0.09;
        } else {
            price = km*0.06;
        }
        System.out.printf("%.2f", price);
    }
}