02. AstrologicalDigits (7 Dec 2011 Morning)

using System;



class AstrologicalDigits
{
    static void Main()
    {
        string numberN = Console.ReadLine();
        decimal sum = 0;

        do
        {
            sum = 0;
            int startIndex = 0;

            while (startIndex < numberN.Length)
            {
                string digit = numberN.Substring(startIndex, 1);
                if (digit != "-" && digit != "." && digit != ",")
                {
                    decimal number = decimal.Parse(digit);
                    //Console.WriteLine(number + " ");
                    sum = sum + number;
                }
                startIndex++;


            }

            numberN = Convert.ToString(sum);
            //Console.WriteLine(sum);
        }
        while (sum > 9);

        Console.WriteLine(sum);



    }
}