using System;
using System.Linq;
using System.Text.RegularExpressions;

public class Test
{
  public static void Main()
  {
    string str = "ghjghjx12klkl122klkl1x33kl0k0l789x2xx6";
    //                  ^^^            ^^^         ^^ ^^

    Match match = Regex.Match(str, @"^(?:x(\d+)|\w)+$");
		
    foreach (Capture x in match.Groups[1].Captures)
      Console.WriteLine(x.Value);
  }
}