using System;

namespace ConsoleApp7
{
    class Program
    {
        static void Main(string[] args)
        {

            string town = Console.ReadLine();
            double sale = double.Parse(Console.ReadLine());

            var comision = -1.0;

            if (town == "Sofia")
            {
                if (sale > 0 && sale <= 500)
                {
                    comision = sale * 0.05;
                    Console.WriteLine($"{comision:F2}");
                }
                else if (sale > 500 && sale <= 1000)
                {
                    comision = sale * 0.07;
                    Console.WriteLine($"{comision:F2}");
                }
                else if (sale > 1000 && sale <= 10000)
                {
                    comision = sale * 0.08;
                    Console.WriteLine($"{comision:F2}");
                }
                else if (sale > 10000)
                {
                    comision = sale * 0.12;
                    Console.WriteLine($"{comision:F2}");
                }
                else
                {
                    Console.WriteLine("error");
                }
            }
            if (town == "Varna")
            {
                if (sale > 0  && sale <= 500)
                {
                    comision = sale * 0.045;
                    Console.WriteLine($"{comision:F2}");
                }
                else if (sale > 500 && sale <= 1000)
                {
                    comision = sale * 0.075;
                    Console.WriteLine($"{comision:F2}");
                }
                else if (sale > 1000 && sale <= 10000)
                {
                    comision = sale * 0.10;
                    Console.WriteLine($"{comision:F2}");
                }
                else if (sale > 10000)
                {
                    comision = sale * 0.13;
                    Console.WriteLine($"{comision:F2}");
                }
                else
                {
                    Console.WriteLine("error");
                }

            }

            if (town == "Plovdiv")
            {
                if (sale > 0 && sale <= 500)
                {
                    comision = sale * 0.055;
                    Console.WriteLine($"{comision:F2}");
                }
                else if (sale > 500 && sale <= 1000)
                {
                    comision = sale * 0.08;
                    Console.WriteLine($"{comision:F2}");
                }
                else if (sale > 1000 && sale <= 10000)
                {
                    comision = sale * 0.12;
                    Console.WriteLine($"{comision:F2}");
                }
                else if (sale > 10000)
                {
                    comision = sale * 0.145;
                    Console.WriteLine($"{comision:F2}");
                }
                else
                {
                    Console.WriteLine("error");
                }
            }
            if (town != "Plovdiv" && town != "Varna" && town != "Sofia")
            {
                Console.WriteLine("error");
            }

        }
    }
}