using System;

using System.Collections.Generic;

using System.Collections.ObjectModel;

public class Program

{

    public static void Main()

    {

        var list = new List<String>{ "a", "b", "c" };

        var collection = new ObservableCollection<string>(list);

        foreach(var value in collection)

        {

            Console.WriteLine(value);

        }

        Console.WriteLine("Hello World");

    }

}