using System;

using System.Collections.Generic;

using System.Linq;

​

public class Program

{

    public static void Main()

    {

        Console.WriteLine(string.Join(", ", Parse("FDENR8027ROR 0.10-CTW-SI2-2-0-0-A4")));

        Console.WriteLine(string.Join(", ", Parse("FDENR7932ROR-1-0-0-A2 ")));

        Console.WriteLine(string.Join(", ", Parse("FDENS3311-4-5-105-A2")));

        Console.WriteLine(string.Join(", ", Parse("FDENS1759-T-6-1-107-A3")));

    }

​

    public static List<string> Parse(string str)

    {

        string[] parts = str.Split('-');

        string first = string.Join("-", parts.Take(parts.Length - 4));

        List<string> result = new List<string>{string.Join("-", parts.Take(parts.Length - 4))};

        result.AddRange(parts.Skip(parts.Length - 4).Take(4));

        return result;

    }

}