using System;

using System.Collections.Generic;

using System.Collections.ObjectModel;

public class Program

{

    public static void Main()

    {

        foreach (TimeZoneInfo timeZone in TimeZoneInfo.GetSystemTimeZones()){

            Console.WriteLine("{0}: {1}", timeZone.Id, timeZone.DisplayName);

        }

        Console.WriteLine(TimeZoneInfo.GetSystemTimeZones().Count);

    }

}