--- pl:prolog:pllib:factorial [2019/06/27 15:50]
+++ pl:prolog:pllib:factorial [2019/06/27 15:50] (aktualna)
@@ Linia 1: / Linia 1: @@
+====== Factorial ======
+{{tag>math recursion}}
+===== Description =====
+Factorial
+**Source**:  The Art of Prolog
+===== Download =====
+Program source code: {{factorial.pl}}
+===== Listing =====
+<code prolog>
+/*
+	factorial(N,F) :- F equals N factorial.
+*/
+	factorial(0,s(0)).
+	factorial(s(N),F) :- factorial(N,F1), times(s(N),F1,F).
+	times(0,X,0).
+	times(s(X),Y,Z) :- times(X,Y,XY), plus(XY,Y,Z).
+	plus(0,X,X) :- natural_number(X).
+	plus(s(X),Y,s(Z)):- plus(X,Y,Z).
+	natural_number(0).
+	natural_number(s(X)) :- natural_number(X).
+%	Program 3.6: Computing fa
+ctorials
+</code>
+===== Comments =====
+RTERR: No permission to redefine built-in predicate 'plus/3'

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

AIwiki

Menu