title: Einstein's riddle
body: <p>I am new to Prolog and I'm trying to model a riddle like the Einstein riddle, also known as the Zebra riddle, (but with 10 houses and 30 hints) in Prolog and I'm using this model example as a starting point:</p>
  
  <p><a href="http://www.baptiste-wicht.com/2010/09/solve-einsteins-riddle-using-prolog/" rel="nofollow">http://www.baptiste-wicht.com/2010/09/solve-einsteins-riddle-using-prolog/</a></p>
  
  <p>But in my riddle, i have to be able to say that X is right of Y. And I don't mean directly right, but right of in the list. So Y can be in house 1, while X in house 9.</p>
  
  <p>How can I do this in Prolog? I was thinking about a predicate which says that Y is a member of the list constructed by taking X and all elements before X out of that list, but I'm not sure how to do that or make that so that I can fit it in the before mentioned example.</p>