PrintLongSequence

using System;


namespace App1
{
    class PrintLongSequence
    {
        static void Main()
        {
            for (short i = 2; i <= 1001; i++)
            {
                bool isMaxVal = (i != 1001);
                if (i % 2 == 0)
                {
                    Console.Write(i + ",");
                }
                else
                {
                    Console.Write(((-1) * i) + ((isMaxVal) ? "," : "\n"));
                };

            }
        }
    }
}