Trade_Comissions

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

namespace Trade_Comissions
{
    class Trade_Comissions
    {
        static void Main(string[] args)
        {
            string sity = Console.ReadLine().ToLower();
            double sales = double.Parse(Console.ReadLine());
            var commission = -1.0;
            if (sity == "sofia")
            {
                if      ((sales >= 0)  && (sales <= 500))      commission = 0.05;
                else if ((sales > 500) && (sales <= 1000))     commission = 0.07;
                else if ((sales >1000) && (sales <= 10000))    commission = 0.08;
                else if (sales >10000)                         commission = 0.12;
            }
            else if (sity == "varna")
            {
                if ((sales >= 0) && (sales <= 500))            commission = 0.045;
                else if ((sales > 500)  && (sales <= 1000))    commission = 0.075;
                else if ((sales > 1000) && (sales <= 10000))   commission = 0.10;
                else if (sales > 10000)                        commission = 0.13;
            }
            else if (sity == "plovdiv")
            {
                if ((sales >= 0)        && (sales <= 500))     commission = 0.055;
                else if ((sales > 500)  && (sales <= 1000))    commission = 0.08;
                else if ((sales > 1000) && (sales <= 10000))   commission = 0.12;
                else if (sales > 10000)                        commission = 0.145;
            }
            if (commission > 0) Console.WriteLine("{0:f2}", sales * commission);
            else Console.WriteLine("error");
        }
    }
}