using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

        var c = new Car("Name", "Model", "Engine");

        Console.WriteLine(c.engine.engineNumber);

    }

  class Car

  {

    string name;

    string model;

    public Engine engine;

​

    public Car(string name, string model, string engineNumber)

    {

      this.name = name;

      this.model = model;

      this.engine = new Engine(engineNumber);

    }

  }

    class Engine

    {

      public string engineNumber;

      public Engine(string engineNumber)

      {

        this.engineNumber = engineNumber;

      }

    }   

​

}