using System;

public class Program

{

    public static void Main()

    {

        var t = new Ipad();

        ISpeakerVolume s = t;

        ILcdBrightness l = t;

        s.Increase();

        l.Increase();

        s.TurnOn();

        l.TurnOn();

    }

}

​

interface ISpeakerVolume

{

    void Increase();

    void TurnOn();

​

}

interface ILcdBrightness

{

    void Increase();

    void TurnOn();

}

​

abstract class Tablet : ISpeakerVolume, ILcdBrightness

{

    // C# enforces us to repeat all the interface members on the implementing abstract class or concrete class

    public void Increase()

    {

        Console.WriteLine("Yeah");

    }

    void ISpeakerVolume.TurnOn()

    {

        Console.WriteLine("Speaker On");

    }

    void ILcdBrightness.TurnOn()

    {

        Console.WriteLine("LCD On");

    }

}

​

class Ipad : Tablet

{

}