Между двумя девятками в числе Pi C#

Между двумя девятками в числе Pi C#

using System;

namespace ConsoleApplication1
{

    class Program
    {
        static void Main()
        {
            string s = "3,141592653589793238469";
            Console.WriteLine("{0}", s);




            int first = s.IndexOf('9'), second = first >= 0 ? s.IndexOf('9', first + 1) : -1;
            int count = first != second && second >= 0 ? second - first - 1 : -1;

            int three = second >= 0 ? s.IndexOf('9', second + 1) : -1;
            int count2 = second != three && three >= 0 ? three - second - 1 : -1;

            int four = three >= 0 ? s.IndexOf('9', three + 1) : -1;
            int count3 = three != four && four >= 0 ? four - three - 1 : -1;

            Console.WriteLine("между двумя девятками находятся {0} потом, {1} потом, {2} ", count, count2, count3);



        }
    }
}