title: Remove parts of a string with PHP
body: <p>I have an input box that tells uers to enter a link from imgur.com
  I want a script to check the link is for the specified site but I'm not sue how to do it?</p>
  
  <p>The links are as follows: <a href="http://i.imgur.com/He9hD.jpg" rel="nofollow">http://i.imgur.com/He9hD.jpg</a>
  Please note that after the /, the text may vary e.g. not be a jpg but the main domain is always <a href="http://i.imgur.com/" rel="nofollow">http://i.imgur.com/</a>.</p>
  
  <p>Any help appreciated.
  Thanks, Josh.(Novice)</p>