PrintSequence

using System;

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