title: Example of 'a subroutine may have several entry and exit points'
body: <p>I'm reading the paper of <a href="http://en.wikipedia.org/wiki/Non-structured_programming" rel="nofollow">Non structured programming</a>, and found it says:</p>
  
  <blockquote>
    <p>Unlike a procedure, a subroutine may have several entry and exit points, and a direct jump into or out of subroutine is (theoretically) allowed</p>
  </blockquote>
  
  <p>I can't understand it, could anyone give me an code sample of:</p>
  
  <ul>
  <li>a subroutine may have several entry and exit points</li>
  <li>a direct jump into or out of subroutine</li>
  </ul>
  
  <p>Thanks</p>