title: Associative array, sum values of the same key
body: <p>So I have this associative array (dump done with kint) </p>
  
  <p><img src="https://i.stack.imgur.com/wItoR.jpg" alt="dump done with Kint">
  d </p>
  
  <p>Instead of having the key "<code>Conference</code>" repeating 3 times. I want to have it just once and sum the 3 values into one in order to have something like:</p>
  
  <p>Conference : 4534</p>
  
  <p>And same thing for all other keys that are repeating..</p>
  
  <p>Is there a native function that can do that ?</p>