Response.Redirect(Request.UrlReferrer.ToString().Length < 1 ? (Request.Url.ToString().IndexOf("?") >= 0 ? (Request.Url.ToString().IndexOf("mark=") >= 0 ? (System.Text.RegularExpressions.Regex.Replace(Request.Url.ToString(), "mark=[^&]*", "mark=0")) : (Request.Url.ToString() + "&mark=0")) : (Request.Url.ToString() + "?mark=0")) : (Request.UrlReferrer.ToString().IndexOf("?") >= 0 ? (Request.UrlReferrer.ToString().IndexOf("mark=") >= 0 ? (System.Text.RegularExpressions.Regex.Replace(Request.UrlReferrer.ToString(), "mark=[^&]*", "mark=0")) : (Request.UrlReferrer.ToString() + "&mark=0")) : (Request.UrlReferrer.ToString() + "?mark=0")));