﻿public abstract class D1 : C {
    protected override sealed void Virtual() {
        base.Virtual();
        System.Console.WriteLine("now sealed");
    }

    protected abstract int Abstract(int i);

	public Inner GetInner()	{
		return new Inner();
	}

	public sealed class Inner {
		public readonly int Number;
		public string Text { get; protected set; }
	}
 }