Нужна помощь в понимании некоторых частей «15 Puzzle Game» на C ++ [закрыто]

Для записей - я использовал этот способ

byte[] bytes = memoryStream.ToArray();

                //Save pdf in the temporary location.
System.IO.File.WriteAllBytes(Server.MapPath("~/TempReports/") + lbReports.Text + "_JEA.pdf", bytes);

/*This is a page counter - it stamps the number of pages in the document. 
 It will read dynamically the 'document' that was just closed above [document.Close();] from the location, 
 then in memory will write the new content plus the one from [byte[] bytes = memoryStream.ToArray();] 
 Solution has been applied from: https://www.aspsnippets.com/Articles/iTextSharp-Add-Page-numbers-to-existing-PDF-using-C-and-VBNet.aspx
 */
try
{
    File.ReadAllBytes(Server.MapPath("~/TempReports/") + lbReports.Text + "_JEA.pdf");
    iTextSharp.text.Font blackFont = FontFactory.GetFont("Arial", 7, iTextSharp.text.Font.BOLD, BaseColor.BLACK);
    using (MemoryStream stream = new MemoryStream())
    {
        PdfReader reader = new PdfReader(bytes);
        using (PdfStamper stamper = new PdfStamper(reader, stream))
        {
            int pages = reader.NumberOfPages;
            for (int i = 1; i <= pages; i++)
            {
                ColumnText.ShowTextAligned(stamper.GetUnderContent(i),
                 @Element.ALIGN_LEFT, new Phrase(lbReports.Text + " - HD - JEA", blackFont), 63f, 24f, 0);

                ColumnText.ShowTextAligned(stamper.GetUnderContent(i),
                @Element.ALIGN_CENTER, new Phrase("Page " + i.ToString() + " of " + pages, blackFont), 300f, 24f, 0);

                ColumnText.ShowTextAligned(stamper.GetUnderContent(i),
                @Element.ALIGN_RIGHT, new Phrase("" + DateTime.Now, blackFont), 549f, 24f, 0);
            }

            txConnection.Text = "This report contains " + pages + " page(s)";
        }

        bytes = stream.ToArray();

    }//End of page counter

    /*System.IO.File.WriteAllBytes will write all bytes to file again*/

    System.IO.File.WriteAllBytes(Server.MapPath("~/TempReports/") + lbReports.Text + "_JEA.pdf", bytes);

    // Temporary path that is used to display the pdf in the embed.
    System.IO.File.WriteAllBytes(Server.MapPath("~/TempReports/ReportsEmbed/") + lbReports.Text + "_JEA.pdf", bytes);

    /*this is what sends the PDF to the embed viewer object
     The ltEmbed is what receives the plugin to dispplay the file*/

    string embed = "";

    ltEmbed.Text = string.Format(embed, ("http://localhost:65423/TempReports/ReportsEmbed/") + lbReports.Text + "_JEA.pdf");
    memoryStream.Close();

    this.Context.ApplicationInstance.CompleteRequest();
}
catch (DocumentException exe)
{
    txConnection.Text = "There has been an error generating the file. Please try again. Error: " + exe;
}