title: XPath Get first element of subset
body: <p>I have XML like this:</p>
  
  <pre><code>&lt;AAA&gt;
      &lt;BBB aaa="111" bbb="222"&gt;
          &lt;CCC/&gt;
          &lt;CCC xxx="555" yyy="666" zzz="777"/&gt;
      &lt;/BBB&gt;
      &lt;BBB aaa="999"&gt;
          &lt;CCC xxx="qq"/&gt;
          &lt;DDD xxx="ww"/&gt;
          &lt;EEE xxx="oo"/&gt;
      &lt;/BBB&gt;
      &lt;BBB&gt;
          &lt;DDD xxx="oo"/&gt;
      &lt;/BBB&gt;
  &lt;/AAA&gt;
  </code></pre>
  
  <p>I want to get first <code>&lt;CCC&gt;</code> element. But with XPath expression <code>//*/CCC[1]</code> I have got two <code>&lt;CCC&gt;</code> elements. Each of them is the first elemet in <code>&lt;BBB&gt;&lt;/BBB&gt;</code> context. How to get first element in subset?</p>