title: Sort and Count Unique value of Array
body: <p>I have a array with thousand values.</p>
  
  <p><code>$arr = array('Stone', 'Gem', 'Star', ..., 'Star', 'Rock', 'Salt', ..., 'Metal', 'Cotton', 'Gem',...);</code></p>
  
  <p>my problem now is how can I count the values of the array.. for example:</p>
  
  <pre><code>Stone = 234
  Gem = 231
  Star = 123
  Rock = 98
  Salt = 265
  ...
  </code></pre>
  
  <p>any idea about this?</p>