using System;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

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

        lstString.Add("Project.Beta.Version.Rule");     

        lstString.Add("Project.Program.Table");

        lstString.Add("Project.Program");

        lstString.Add("Zip.File");

        var root = new RfClass();

        foreach(var x in lstString)

        {

            string[] words = x.Split('.');

            CreateTree(root, words, 0);

        }

        Display(root);

    }   

    public static void CreateTree(RfClass root, string[] words, int idx)

    {

        RfClass next;

        if (false == root.lstRefClass.TryGetValue(words[idx], out next))

        {

            next = new RfClass();

            root.lstRefClass.Add(words[idx], next);

        }

        if (idx + 1 < words.Length)

            CreateTree(next, words, idx + 1);

    }

    public static void Display(RfClass root, int indent = 0)

    {

        foreach(var p in root.lstRefClass)

        {

            Console.WriteLine("{0} key: {1} ",new string('\t', indent), p.Key);

            Console.WriteLine("{0} Value: Dictionary<string, RfClass>", new string('\t', indent));

            Display(p.Value, indent+1);

        }

    }

    public class RfClass

    {

       public Dictionary<string, RfClass> lstRefClass = new Dictionary<string, RfClass>();

    }

}