@@ Linia 1: / Linia 1: @@
+====== Predecessor ======
+{{tag>family recursion}}
+===== Description =====
+Four versions of the predecessor program.
+**Source**:  PROLOG programming for artificial intelligence, 3rd Edition, Harlow, 2001, ISBN 0-201-40375-7.
+===== Download =====
+Program source code: {{predecessor.pl}}
+===== Listing =====
+<code prolog>
+% Figure 2.16   Four versions of the predecessor program.
+% Four versions of the predecessor program
+% The original version
+pred1( X, Z)  :-
+   parent( X, Z).
+pred1( X, Z)  :-
+   parent( X, Y),
+   pred1( Y, Z).
+% Variation a: swap clauses of the original version
+pred2( X, Z)  :-
+   parent( X, Y),
+   pred2( Y, Z).
+pred2( X, Z)  :-
+   parent( X, Z).
+% Variation b: swap goals in second clause of the original version
+pred3( X, Z)  :-
+   parent( X, Z).
+pred3( X, Z)  :-
+   pred3( X, Y),
+   parent( Y, Z).
+% Variation c: swap goals and clauses of the original version
+pred4( X, Z)  :-
+   pred4( X, Y),
+   parent( Y, Z).
+pred4( X, Z)  :-
+   parent( X, Z).
+</code>
+===== Comments =====

pl/prolog/pllib/predecessor.txt · ostatnio zmienione: 2019/06/27 15:50 (edycja zewnętrzna)

AIwiki

Menu