PrintASequence

using System;

class PrintASequence
{
    static void Main()
    {
        for (int number = 2; number < 12; number++)
        {
            if (number % 2 == 0)
            {
                Console.Write(number);
            }
            else
            {
                Console.Write(-number);
            }
            if (number < 11)
            {
                Console.Write(",");
            }

        }
        Console.ReadKey();
    }
}