title: How to merge multidimensional arrays in php
body: <p>I have the following case in php</p>
  
  <pre><code>$one = array('one' =&gt; 1,  2 =&gt; array('intro'=&gt; 'something', 'short' =&gt; 'short')); 
  $two = array('intro' =&gt; 'something_new');
  $three = array_merge($one,$two);
  </code></pre>
  
  <p>what I wanted to do is to change the one[2][intro] to two[intro]
  what it does is append the "two" array into the "one"</p>
  
  <p>How I could change the value of the first array with the second ones by knowing only the key but not in which level is this key?</p>