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CSharp · Console

/Program.cs

using System;
					
public class Program
{
	public static void Main()
	{
        var derived = new Derived();
		Console.WriteLine(derived.Hello());
	}
}

public class Base
{
    public string Hello(){ 
		return "Hello " + World();
	}
	
	public string World() => "world";
}

public class Derived : Base
{
    public new string World() => "Not used";
}