using System;

using System.Collections.Generic;

using System.Linq;

​

public class Program

{

    static List<string> FilterIndexingFromSiteIndex(List<string> indexing)

    {

        return indexing.Where((node) =>

                              {

                                  List<string> parts = node.Split('>').Select(n => n.Trim()).ToList();

​

                                  if (parts.Count != 3)

                                  {

                                      return false;

                                  }

​

​

                                  return parts[2] != null;

​

                              }).ToList();

    }

    public static void Main()

    {

        List<string> indexing = new List<string>();

        indexing.Add("");

        indexing.Add(",");

        indexing.Add(",,");

        indexing.Add(",,,");

        indexing.Add("1");

        indexing.Add("1,");

        indexing.Add("1,,");

        indexing.Add("1,2");

        indexing.Add("1,2,");

        indexing.Add("1,2,3");

        Console.WriteLine(string.Join(",",FilterIndexingFromSiteIndex(indexing)));

    }

}