using System;

namespace Comission
{
    class Program
    {
        static void Main(string[] args)
        {
            bool error = false;
            double percent = 0;
            string town = Console.ReadLine();
            double sells = double.Parse(Console.ReadLine());
            switch (town)
            {
                case "Sofia":
                    if (sells > 10000)
                    { percent = 12; }
                    else if (sells > 1000)
                    { percent = 8; }
                    else if (sells > 500)
                    { percent = 7; }
                    else if (sells >= 0)
                    { percent = 5; }
                    else
                    { error = true; }
                    break;
                case "Varna":
                    if (sells > 10000)
                    { percent = 13; }
                    else if (sells > 1000)
                    { percent = 10; }
                    else if (sells > 500)
                    { percent = 7.5; }
                    else if (sells >= 0)
                    { percent = 4.5; }
                    else
                    { error = true; }
                    break;
                case "Plovdiv":
                    if (sells > 10000)
                    { percent = 14.5; }
                    else if (sells > 1000)
                    { percent = 12; }
                    else if (sells > 500)
                    { percent = 8; }
                    else if (sells >= 0)
                    { percent = 5.5; }
                    else
                    { error = true; }
                    break;
                default:
                    error = true;
                    break;

            }
            if (error == false)
            { Console.WriteLine($"{(sells * percent * 0.01):f2}"); }
            else
            { Console.WriteLine("error"); }


        }
    }
}