factors.pl

factors.pl

@@ -0,0 +1,17 @@
+% factors(N,Fs) <- Fs is the list of prime factors of N
+factors(1,[1]).
+factors(X,[Factor|Fs]) :-
+   X > 1,
+   between(2,X,Factor),    % generate candidate factor, lowest first
+   (X mod Factor) =:= 0,   % test Factor is divisor of X
+   !,                      % if so, stop generating!
+   Rem is X // Factor,     % proceed with remainder
+   factors(Rem,Fs).
+
+/** &lt;examples&gt;
+
+?-factors(27,Fs).
+?-factors(28,Fs).
+?-factors(29,Fs).
+
+*/

tiles.pl

@@ -1,9 +1,9 @@
-board_size(7). % odd number, at least 3
+board_size(9). % odd number, at least 3
 
 eval_pos(Pos,Value):-
 	%% uncomment exactly one of the following lines
-	bLeftOfw(Pos,Value).    
-	%outOfPlace(Pos,1,Value). 
+	%bLeftOfw(Pos,Value).    
+	outOfPlace(Pos,1,Value). 
 
 /*
  * Moves are represented as triples m(From,To,Cost).