title: is FILO always LIFO?
body: <p>A stack is referred to as a Last-In-First-Out (LIFO) and First-In-Last-Out (FILO) structure.</p>
  
  <p>Is there any <strong>data structure that is LIFO but not FILO</strong> (or other direction)  ? A counter example that proves "FILO doesn't always mean LIFO"</p>