title: Prolog, program to determine if two lists are not equal
body: <p>I want to build a Prolog program to determine if two lists, provided as arguments, are not equal.</p>
  
  <p>This is what I did so far.</p>
  
  <pre><code>not-equal([],[a|_]).
  not-equal([a|_],[H|T]):-not-equal(a,T).
  </code></pre>