2006-08-25 19:50:35 +00:00
										 
									 
								 
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								/*************************************************************************
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								*									 *
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								*	 YAP Prolog 							 *
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								*									 *
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								*	Yap Prolog was developed at NCCUP - Universidade do Porto	 *
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								*									 *
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								* Copyright L.Damas, V.S.Costa and Universidade do Porto 1985-1997	 *
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								*									 *
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								**************************************************************************
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								*									 *
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								* File:		nb.yap							 *
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								* Last rev:	5/12/99							 *
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								* mods:									 *
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								* comments:	non-backtrackable data-structures			 *
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								*									 *
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								*************************************************************************/
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											2015-11-18 15:06:25 +00:00
										 
									 
								 
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								/**
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								 * @file   nb.yap
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								 * @author VITOR SANTOS COSTA <vsc@VITORs-MBP.lan>
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								 * @date   Tue Nov 17 23:18:13 2015
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								 * 
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								 * @brief  stub for global (non-backtrackable) variables.
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								 * 
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								 * 
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								*/
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								:- module(nb, [
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									       nb_create_accumulator/2,
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									       nb_add_to_accumulator/2,
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									       nb_accumulator_value/2,
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									       nb_queue/1,
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									       nb_queue/2,
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									       nb_queue_close/3,
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									       nb_queue_enqueue/2,
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									       nb_queue_dequeue/2,
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									       nb_queue_peek/2,
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									       nb_queue_empty/1,
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									       nb_queue_size/2,
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									       nb_queue_replace/3,
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									       nb_heap/2,
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									       nb_heap_close/1,
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									       nb_heap_add/3,
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									       nb_heap_del/3,
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									       nb_heap_peek/3,
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									       nb_heap_empty/1,
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									       nb_heap_size/2,
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									       nb_beam/2,
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									       nb_beam_close/1,
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									       nb_beam_add/3,
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									       nb_beam_del/3,
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									       nb_beam_peek/3,
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									       nb_beam_empty/1,
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								%	       nb_beam_check/1,
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									       nb_beam_size/2]).
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								/** @defgroup nb Non-Backtrackable Data Structures
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											2015-01-04 23:58:23 +00:00
										 
									 
								 
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								@ingroup library
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											2014-09-11 14:06:57 -05:00
										 
									 
								 
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								@{
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								The following routines implement well-known data-structures using global
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								non-backtrackable variables (implemented on the Prolog stack). The
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								data-structures currently supported are Queues, Heaps, and Beam for Beam
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								search. They are allowed through `library(nb)`. 
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								*/
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								/** @pred nb_beam(+ _DefaultSize_,- _Beam_) 
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								Create a  _Beam_ with default size  _DefaultSize_. Note that size
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								is fixed throughout.
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								*/
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								/** @pred nb_beam_add(+ _Beam_, + _Key_, + _Value_) 
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								Add  _Key_- _Value_ to the beam  _Beam_. The key is sorted on
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								 _Key_ only.
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								*/
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								/** @pred nb_beam_close(+ _Beam_) 
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								Close the beam  _Beam_: no further elements can be added.
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								*/
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								/** @pred nb_beam_del(+ _Beam_, - _Key_, - _Value_) 
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								Remove element  _Key_- _Value_ with smallest  _Value_ in beam
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								 _Beam_. Fail if the beam is empty.
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								*/
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								/** @pred nb_beam_empty(+ _Beam_) 
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								Succeeds if   _Beam_ is empty.
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								 */
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								/** @pred nb_beam_peek(+ _Beam_, - _Key_, - _Value_)) 
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								 _Key_- _Value_ is the element with smallest  _Key_ in the beam
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								 _Beam_. Fail if the beam is empty.
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								*/
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								/** @pred nb_beam_size(+ _Beam_, - _Size_) 
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								Unify  _Size_ with the number of elements in the beam   _Beam_.
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								*/
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								/** @pred nb_heap(+ _DefaultSize_,- _Heap_) 
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								Create a  _Heap_ with default size  _DefaultSize_. Note that size
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								will expand as needed.
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								*/
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								/** @pred nb_heap_add(+ _Heap_, + _Key_, + _Value_) 
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								Add  _Key_- _Value_ to the heap  _Heap_. The key is sorted on
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								 _Key_ only.
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								*/
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								/** @pred nb_heap_close(+ _Heap_) 
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								Close the heap  _Heap_: no further elements can be added.
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								*/
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								/** @pred nb_heap_del(+ _Heap_, - _Key_, - _Value_) 
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								Remove element  _Key_- _Value_ with smallest  _Value_ in heap
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								 _Heap_. Fail if the heap is empty.
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								*/
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								/** @pred nb_heap_empty(+ _Heap_) 
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								Succeeds if   _Heap_ is empty.
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								*/
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								/** @pred nb_heap_peek(+ _Heap_, - _Key_, - _Value_)) 
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								 _Key_- _Value_ is the element with smallest  _Key_ in the heap
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								 _Heap_. Fail if the heap is empty.
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								*/
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								/** @pred nb_heap_size(+ _Heap_, - _Size_) 
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								Unify  _Size_ with the number of elements in the heap   _Heap_.
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								*/
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								/** @pred nb_queue(- _Queue_) 
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								Create a  _Queue_.
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								*/
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								/** @pred nb_queue_close(+ _Queue_, - _Head_, ? _Tail_) 
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								Unify the queue   _Queue_ with a difference list
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								 _Head_- _Tail_. The queue will now be empty and no further
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								elements can be added.
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								*/
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								/** @pred nb_queue_dequeue(+ _Queue_, - _Element_) 
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								Remove  _Element_ from the front of the queue   _Queue_. Fail if
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								the queue is empty.
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								*/
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								/** @pred nb_queue_empty(+ _Queue_) 
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								Succeeds if   _Queue_ is empty.
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								*/
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								/** @pred nb_queue_enqueue(+ _Queue_, + _Element_) 
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								Add  _Element_ to the front of the queue   _Queue_.
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								*/
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								/** @pred nb_queue_peek(+ _Queue_, - _Element_) 
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								 _Element_ is the front of the queue   _Queue_. Fail if
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								the queue is empty.
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								*/
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								/** @pred nb_queue_size(+ _Queue_, - _Size_) 
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								Unify  _Size_ with the number of elements in the queue   _Queue_.
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								*/
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