Harkonnikova programovaci Mystery Cache

using System;
using System.Collections.Generic;
using System.Globalization;
using System.Linq;

namespace PrimeNumbers
{
    internal static class Extensions
    {
        internal static bool IsPrime(this int number)
        {
            if ((number % 2) == 0)
            {
                return number == 2;
            }
            var sqrt = (int)Math.Sqrt(number);
            for (var t = 3; t <= sqrt; t = t + 2)
            {
                if (number % t == 0)
                {
                    return false;
                }
            }
            return number != 1;
        }

        internal static string BuildCoordinates(this double number)
        {
            var strNumber = number.ToString(CultureInfo.InvariantCulture);
            return string.Format("N 50° {0}{1}.{2}{3}{4} E 014° {5}{6}.{7}{8}{9}",
            strNumber[6], strNumber[2], strNumber[0],
            int.Parse(strNumber[5].ToString(CultureInfo.InvariantCulture)) + 1, strNumber[9],
            strNumber[8], strNumber[10],
            int.Parse(strNumber[4].ToString(CultureInfo.InvariantCulture)) + 2, strNumber[3],
            int.Parse(strNumber[3].ToString(CultureInfo.InvariantCulture)) - 4);
        }
    }

    class Program
    {
        static void Main()
        {
            const int initialCount = 3000000;
            var list = new List<int>(initialCount);
            var primeNumbers = new HashSet<int>();
            for (var i = 0; i <= initialCount; i++)
            {
                list.Add(i);
            }
            foreach (var i in list.Where(i => i.IsPrime()))
            {
                primeNumbers.Add(i);
            }
            var number
            = primeNumbers.Aggregate<int, int>(1, (current, count) => count + current);
            Console.WriteLine(number.BuildCoordinates());
        }
    }
}