using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace StariIzpiti
{
    class Program
    {
        static void Main(string[] args)
        {
            var kilometersNeeded = double.Parse(Console.ReadLine());
            var travelTime = Console.ReadLine();
            var taxiStartPrice = 0.7;
            var taxiDailyPrice = 0.79;
            var taxiNightPrice = 0.90;
            var busPrice = 0.09;
            var trainPrice = 0.06;

            var currentTotalPrice = 0.0;
            if (kilometersNeeded >= 100)
            {
                currentTotalPrice = kilometersNeeded * trainPrice;
            }
            else if (kilometersNeeded >=20)
            {
                currentTotalPrice = kilometersNeeded * busPrice;
            }
            if (travelTime == "day")
            {
                currentTotalPrice = taxiStartPrice + kilometersNeeded * taxiDailyPrice;
            }
            else
            {
                currentTotalPrice = taxiStartPrice + kilometersNeeded * taxiNightPrice;
            }
            Console.WriteLine($"{currentTotalPrice:f2}");
        }
    }
}