title: Finding the difference between two XML files
body: <p>I have built two XML files that map the content of a given folder:</p>
  
  <pre><code>&lt;root&gt;
      &lt;folder name="C:\a\b" permision="yes" folderCount="1"&gt;
          &lt;folders&gt;
              &lt;folder name="C:\a\b\c" permision="yes" folderCount="1"&gt;
                  &lt;folders&gt;
                      &lt;folder name="C:\a\b\c\e" permision="yes" folderCount="0"&gt;
                  &lt;folders/&gt;
                  &lt;files&gt;
                      &lt;file name="401-1.htm"/&gt;
                      &lt;file name="401-2.htm"/&gt;
                      &lt;file name="401-3.htm"/&gt;                              
                  &lt;/files&gt;
              &lt;/folder&gt;
              &lt;folder name="C:\a\b\d" permision="yes" folderCount="0"&gt;
                  &lt;folders/&gt;
                  &lt;files&gt;
                      &lt;file name="401-4.htm"/&gt;
                      &lt;file name="401-5.htm"/&gt;
                      &lt;file name="401-3.htm"/&gt;                                
                  &lt;/files&gt;
              &lt;/folder&gt;
          &lt;/folders&gt;
          &lt;files/&gt;
      &lt;/folder&gt;
  &lt;/root&gt;
  </code></pre>
  
  <p>I'd like to know if there is a way to find the difference between the files.</p>
  
  <p>(One file is the old state and the second is the new state, and it's only possible to add files and not remove them. It would be great to remove identical nodes from the new state so only the new files will be left).</p>