title: Finding empty directories
body: <p>I need to find empty directories for a given list of directories.
  Some directories have directories inside it.</p>
  
  <p>If inside directories are also empty I can say main directory is empty otherwise it's not empty.</p>
  
  <p>How can I test this?</p>
  
  <p>For example:</p>
  
  <pre><code>A&gt;A1(file1),A2 this is not empty beacuse of file1
  B&gt;B1(no file) this is empty
  C&gt;C1,C2 this is empty
  </code></pre>