using System;

using System.IO;

using System.IO.Compression;

using System.Text.Json;

using System.Text;

public class Program

{

    public static void Main()

    {

        string s = "helloworld";

        using (var stream = new MemoryStream())

        {

            using (var gzipStream = new GZipStream(stream, CompressionMode.Compress))

            {

                gzipStream.Write(Encoding.UTF8.GetBytes(s));

                gzipStream.Flush();

                string hexString = BitConverter.ToString(stream.ToArray());

                Console.WriteLine(hexString);

            }

        }

    }

}