using System;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
using System.Xml;
using System.Xml.Linq;
public class MainClass {
public static void Main() {
XDocument xDocument = new XDocument(
new XElement("Books",
new XElement("Book",
new XAttribute("type", "Author"),
new XElement("FirstName", "A"),
new XElement("LastName", "B"),
new XElement("Nickname", "A"),
new XElement("Nickname", "Null Pointer")),
new XElement("Book",
new XAttribute("type", "Author"),
new XElement("FirstName", "C"),
new XElement("LastName", "D"))));
Console.WriteLine(xDocument);
}
}