Queue

Description

A queue process

Source: The Art of Prolog

Download

Program source code: queue.pl

Listing

/*	
    queue(S) :-
	S is a sequence of enqueue and dequeue operations,
	represented as a list of terms enqueue(X) and dequeue(X).
*/
	:- op(40,xfx,\).
 
	queue(S) :- queue(S,Q\Q).
 
	queue([enqueue(X)|Xs],Q) :-
	   enqueue(X,Q,Q1), queue(Xs,Q1).
	queue([dequeue(X)|Xs],Q) :-
	   dequeue(X,Q,Q1), queue(Xs,Q1).
	queue([],Q).
 
	enqueue(X,Qh\[X|Qt],Qh\Qt).
	dequeue(X,[X|Qh]\Qt,Qh\Qt).
 
%	Program 15.11:	A queue process

Comments

pl/prolog/pllib/queue.txt · ostatnio zmienione: 2017/07/17 08:08 (edycja zewnętrzna)
www.chimeric.de Valid CSS Driven by DokuWiki do yourself a favour and use a real browser - get firefox!! Recent changes RSS feed Valid XHTML 1.0