using System;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        B b= new B(string.Empty,0);

        b.x = "blub";

        b.y = 1;

        changeB(b);

        // side Effect in Method 

        Console.WriteLine(b.x + ":" + b.y);

        List<B> bs = new List<B>();

        bs.Add(b);

        bs.ForEach(item=>{item.y=-2; item.x="blah";});

        // side effect in list 

        Console.WriteLine(((B)bs[0]).x + ":" + ((B)bs[0]).y));      

        Console.WriteLine(b.x + ":" + b.y);

    }

    private static void changeB(B b)

    {

        b.x = "method Changed";

        b.y = -1;

    }

    public class B

    {

        public string x {get; set;}

        public int y {get; set;}

        public B(string x, int y)

        {

            this.x=x;

            this.y=y;

        }

    }

}