using System;

using System.Collections.Generic;

using System.Linq;

public class Program

{

    public static void Main()

    {

        List<string> entries = new List<string>();

        for(var i = 0; i < 1000; i ++)

        {

            entries.Add(i.ToString());  

        }

        var element = entries.FirstOrDefault(e => e == "666");

        Console.WriteLine(element);

        element = "Hallo Welt";

        Console.WriteLine(element);

        Console.WriteLine(entries[666]);

    }

}