using System;

​

public class Vehicle

{

    public void StartEngine(string noiseToMakeWhenStarting)

    {

        Console.WriteLine("Starting engine: {0}", noiseToMakeWhenStarting);

    }

    public void StopEngine(string noiseToMakeWhenStopping)

    {

        Console.WriteLine("Stopping engine: {0}", noiseToMakeWhenStopping);

    }

    public virtual void Drive()

    {

        Console.WriteLine("Default implementation of the Drive method");

    }

    static void doWork()

    {

        Console.WriteLine("\nTesting polymorphism");

        Car myCar =new Car();

        Vehicle v = myCar;

        v.Drive();

        Airplane myPlane = new Airplane();

        v = myPlane;

        v.Drive();

    }

    public static void Main(string[] args)

    {

        doWork();

    }

}

public class Airplane : Vehicle

{

    public void TakeOff()

    {

        Console.WriteLine("Taking off");

    }

    public void Land()

    {

        Console.WriteLine("Landing");

    }

    static void doWork()

    {

        Console.WriteLine("Journey by airplane:");

        Airplane myPlane = new Airplane();

        myPlane.StartEngine("Contact");

        myPlane.TakeOff();

        myPlane.Drive();

        myPlane.Land();

        myPlane.StopEngine("Whirr");

    }

    public override void Drive()

    {

        Console.WriteLine("Flying");

    }

    /*public static void Main(string[] args)

    {

        doWork();

    }*/

}

public class Car : Vehicle

{

    public void Accelerate()

    {

        Console.WriteLine("Accelerating");

    }

    public void Brake()

    {

        Console.WriteLine("Braking");

    }

    static void doWork()

    {

        Console.WriteLine("\nJourney by car:");

        Car myCar = new Car();

        myCar.StartEngine("Brm brm");

        myCar.Accelerate();

        myCar.Drive();

        myCar.Brake();

        myCar.StopEngine("Phut phut");

    }

//  public static void Main(string[] args)

//  {

//      doWork();

//      //Airplane.doWork();

//  }

    public override void Drive()

    {

        Console.WriteLine("Motoring");

    }

}