using System;

​

public class Program

{

    public static void Main()

    {

        Console.WriteLine(new Uri(new Uri("https://server.de/test"), "test"));

        Console.WriteLine(new Uri(new Uri("https://server.de/test"), "/test"));

        Console.WriteLine(new Uri(new Uri("https://server.de/test/"), "test"));

        Console.WriteLine(new Uri(new Uri("https://server.de/test/"), "/test"));

    }

}