title: how to count total number of divs with in a div using php
body: <p>I want to count total number of div within a specific div. How can I do this?
  For Example: </p>
  
  <pre><code>&lt;div class="items"&gt;
     &lt;div class="single_item"&gt;Item 1&lt;/div&gt;
     &lt;div class="single_item"&gt;Item 1&lt;/div&gt;   
     &lt;div class="single_itemitem"&gt;Item 1&lt;/div&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>I want to count all the div containing class name single_item. How can I do this?  </p>