How to get file name of a directory which is lastly opened

string path = Environment.GetFolderPath(Environment.SpecialFolder.Recent);
            var files = Directory.GetFiles(path);
            DateTime[] xys = null;
            int s = 0;
            foreach (string xy in files)
            {
                s++;
            }
            xys = new DateTime[s];
            s = 0;
            foreach (string xy in files)
            {
                FileInfo fi = new FileInfo(xy);
                DateTime dts= fi.LastAccessTime;
                xys[s] = dts;
                s++;
            }

            List<DateTime> lst = new List<DateTime>();
            foreach(DateTime xyt in xys)
            {
              lst.Add(xyt);
            }
            lst.Sort();
            lst.Reverse();
            string stse="";
            string strs = lst.Max(date => date).ToString();
            try
            {
                 stse= lst[2].ToString();
            }
            catch { stse = lst[0].ToString(); };
            

            foreach (string xya in files)
            {
                FileInfo fi = new FileInfo(xya);
                DateTime dts = fi.LastAccessTime;
                string stps = dts.ToString();
                DateTime stpss = Convert.ToDateTime(stps);
                DateTime ne = Convert.ToDateTime(stse);
                int result = DateTime.Compare(stpss, ne);
                if (result==0)
                {
                    string dst = Path.GetFileName(xya);
                    textBox1.Text = dst;
                    break;
                }

            }