title: tree family does not work properly in prolog
body: <p>I'm trying to run a prolog program that represents a tree but when I select option 1 from  menu shows me false.</p>
  
  <p>Code:</p>
  
  <p><a href="https://github.com/carson314/Prolog/blob/master/menus.pl" rel="nofollow">https://github.com/carson314/Prolog/blob/master/menus.pl</a></p>