using System;

namespace ConsoleApp26
{
    class Program
    {
        static void Main(string[] args)
        {
            string city = Console.ReadLine();
            double sells = double.Parse(Console.ReadLine());
            double commision = 0;
            if (city == "Sofia")
            {
                if (sells >= 0 && sells <= 500)
                {
                    commision = sells * 0.05;
                    Console.WriteLine($"{commision:f2}");
                }
                else if (sells > 500 && sells <= 1000)
                {
                    commision = sells * 0.07;
                    Console.WriteLine($"{commision:f2}");
                }
                else if (sells > 1000 && sells <= 10000)
                {
                    commision = sells * 0.08;
                    Console.WriteLine($"{commision:f2}");

                }
                else if (sells > 10000)
                {
                    commision = sells * 0.12;
                    Console.WriteLine($"{commision:f2}");
                }
            }
            else if (city == "Varna")
            {
                if (sells >= 0 && sells <= 500)
                {
                    commision = sells * 0.045;
                    Console.WriteLine($"{commision:f2}");
                }
                else if (sells > 500 && sells <= 1000)
                {
                    commision = sells * 0.075;
                    Console.WriteLine($"{commision:f2}");
                }
                else if (sells > 1000 && sells <= 10000)
                {
                    commision = sells * 0.1;
                    Console.WriteLine($"{commision:f2}");
                }
                else if (sells > 10000)
                {
                    commision = sells * 0.13;
                    Console.WriteLine($"{commision:f2}");
                }
                else
                {
                    Console.WriteLine("error");
                }
            }

            else if (city == "Plovdiv")
            {
                if (sells >= 0 && sells <= 500)
                {
                    commision = sells * 0.055;
                    Console.WriteLine($"{commision:f2}");
                }
                else if (sells > 500 && sells <= 1000)
                {
                    commision = sells * 0.08;
                    Console.WriteLine($"{commision:f2}");
                }
                else if (sells > 1000 && sells <= 10000)
                {
                    commision = sells * 0.12;
                    Console.WriteLine($"{commision:f2}");
                }
                else if (sells > 10000)
                {
                    commision = sells * 0.145;
                    Console.WriteLine($"{commision:f2}");
                }
                else
                {
                    Console.WriteLine("error");
                }

            }
            else if (city != "Sofia" && city != "Varna" && city != "Plovdiv")
            {
                Console.WriteLine("error");
            }

            }
        }
    }