using System;

public class Program

{

    public static void Main()

    {

        DateTime pacific = new DateTime(637413158400000000);

        //DateTime pacific = new DateTime(2020, 6, 18);

        Console.WriteLine(pacific);

        TimeZoneInfo tz = TimeZoneInfo.FindSystemTimeZoneById("Hawaiian Standard Time");

        DateTime utc = TimeZoneInfo.ConvertTimeToUtc(pacific, tz);

        Console.WriteLine(utc);

        TimeZoneInfo sys = TimeZoneInfo.FindSystemTimeZoneById("Eastern Standard Time");

        DateTime fromutc = TimeZoneInfo.ConvertTimeFromUtc(utc, sys);

        Console.WriteLine(fromutc);

        DateTime convert = TimeZoneInfo.ConvertTimeBySystemTimeZoneId(new DateTime(pacific.Ticks), "Pacific Standard Time", "Eastern Standard Time");

        Console.WriteLine(convert);

    }

}