using System.Collections.Generic;

using System;

​

class Car

{

    public string Make   { get; set; }

    public string Model  { get; set; }

    public string Year   { get; set; }

​

    public int FuelLevel { get;set; }

    public int OilLevel  { get; set; }

​

    public Car(string make, string model, string year)

    {

        Make = make;

        Model = model;

        Year = year;

    }

​

    public void Refuel()

    {

        FuelLevel = 100;

    }

}

​

public class Program

{

    public static void Main()

    {

        List<Car> CarsThatJoeOwns = new List<Car> { new Car("Ford", "Explorer", "2005"),

                                                    new Car("Hyundai", "Elantra", "2011") };

​

        // For some reason, Paul owns the exact same types of cars that Joe owns...

        List<Car> CarsThatPaulOwns = new List<Car> (CarsThatJoeOwns);

​

        foreach (Car car in CarsThatPaulOwns)

        {

            car.Refuel(); // <---- does this affect the cars that Joe owns too?

        }

        CarsThatJoeOwns.Dump();

        CarsThatPaulOwns.Dump();

    }

}