Hash autoryzujący, C#

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//Title of this code
//Rextester.Program.Main is the entry point for your code. Don't change it.
//Compiler version 4.0.30319.17929 for Microsoft (R) .NET Framework 4.5

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;

namespace Rextester
{
    public class Program
    {
        public static void Main(string[] args)
        {
            var p = new Program();
            Console.WriteLine(p.Hash(""));
            Console.WriteLine(p.Hash("192.168.0.220/Kontrahenci/36"));
            Console.WriteLine(p.Hash("enova/Kontrahenci/Xslt"));
        }
        
        public string Hash(string url)
        {
            var t = DateTime.Now;
            t = new DateTime(t.Year,t.Month,t.Day,t.Hour,t.Minute/10*10,0);
            var hash = new System.Text.StringBuilder();
            foreach (byte b in System.Security.Cryptography.SHA1.Create().ComputeHash(System.Text.Encoding.UTF8.GetBytes(string.Format("md5({0:yyyyMMddHHmm},{1})",t,url)))) hash.Append(b.ToString("X2"));
            return hash.ToString();
        }
    }
}

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