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			473 lines
		
	
	
		
			14 KiB
		
	
	
	
		
			Prolog
		
	
	
	
	
	
			
		
		
	
	
			473 lines
		
	
	
		
			14 KiB
		
	
	
	
		
			Prolog
		
	
	
	
	
	
| % FINITE and INFINITE DOMAINS		
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| % 910527 ECRC thom fruehwirth
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| % 910913 modified 
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| % 920409 element/3 added
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| % 920616 more CHIP predicates added
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| % 930726 started porting to CHR release
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| % 931014 mult/3 added for CHIC user meeting
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| % 931201 ported to CHR release
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| % 931208 removed special case of integer domain
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| % 940304 element/3 constraint loop fixed
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| % 961017 Christian Holzbaur SICStus mods
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| % 980714 Thom Fruehwirth, some updates reagrding alread_in*
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| 
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| % just quick port from Eclipse CHR library version
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| % does not take advantage of Sicstus CHR library features!
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| 		
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| % Simplifies domains together with inequalities and some more CHIP predicates:
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| % 	element/3, atmost/3, alldistinct/1, circuit/1 and mult/3
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| % It also includes paired (!) domains (see element constraint)
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| 
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| :- use_module( library(chr)).
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| :- use_module( library('chr/getval')).
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| :- use_module( library(lists), [member/2,last/2]).
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| 
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| :- use_module( library(ordsets),
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| 	[
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|           list_to_ord_set/2,
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| 	  ord_intersection/3
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|         ]).
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| 
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| handler domain.
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| 
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| option(already_in_store, on).   
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| option(already_in_heads, off).   % see pragma already_in_heads
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| option(check_guard_bindings, off).
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| 
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| % for domain constraints
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| operator(700,xfx,'::').
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| operator(600,xfx,'..').
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| operator(600,xfx,':').  % clash with module operator?
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| 
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| % for inequality constraints
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| operator(700,xfx,lt).
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| operator(700,xfx,le).
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| operator(700,xfx,gt).
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| operator(700,xfx,ge).
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| operator(700,xfx,ne).
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| 
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| % X::Dom - X must be element of the finite or infinite domain Dom
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| 
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| % Domains can be either numbers (including arithemtic expressions)
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| % or arbitrary ground terms (!), the domain is set with setval(domain,Kind),
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| % where Kind is either number or term. Default for Kind is term.
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| 
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| :- setval(domain,term). 	% set default
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| 
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| 
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| % INEQUALITIES ===============================================================
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| % inequalities over numbers (including arithmetic expressions) or terms
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| 
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| constraints lt/2,le/2,ne/2.
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| 
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| A gt B :- B lt A.				% constraints gt/2,ge/2
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| A ge B :- B le A.
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| % some basic simplifications
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| A lt A <=> fail.
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| A le A <=> true.
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| A ne A <=> fail.
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| A lt B,B lt A <=> fail.
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| A le B,B le A <=> A=B.
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| A ne B \ B ne A <=> true.
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| % for number domain, allow arithmetic expressions in the arguments
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| A  lt  B <=> domain(number),ground(A),\+ number(A) | A1 is A, A1 lt B.
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| B  lt  A <=> domain(number),ground(A),\+ number(A) | A1 is A, B lt A1.
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| A  le  B <=> domain(number),ground(A),\+ number(A) | A1 is A, A1 le B.
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| B  le  A <=> domain(number),ground(A),\+ number(A) | A1 is A, B le A1.
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| A  ne  B <=> domain(number),ground(A),\+ number(A) | A1 is A, A1 ne B.
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| B  ne  A <=> domain(number),ground(A),\+ number(A) | A1 is A, B ne A1.
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| % use built-ins to solve the predicates if arguments are known
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| A  lt  B <=> ground(A),ground(B) | (domain(number) -> A < B ; A @< B).
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| A  le  B <=> ground(A),ground(B) | (domain(number) -> A =< B ; A @=< B).
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| A  ne  B <=> ground(A),ground(B) | (domain(number) -> A =\= B ; A \== B).
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| 
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| 
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| 
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| % FINITE and INFINITE DOMAINS ================================================
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| 
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| constraints (::)/2.
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| 
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| % enforce groundness of domain expression
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|  X::Dom <=> nonground(Dom) | 
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|         raise_exception( instantiation_error(X::Dom,2)).
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| 
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| constraints labeling/0.
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| 
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| labeling, (X::[Y|L]) # Ph <=> 
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| 	member(X,[Y|L]), labeling
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|     pragma passive(Ph).
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| 
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| % binary search by splitting domain in halves
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| labeling, (X::Min:Max) # Ph <=> domain(number),Min+0.5<Max |  % ensure termination
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| 	(integer(Min),integer(Max) ->  % assume we have integer domain
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| 	Mid is (Min+Max)//2, Next is Mid+1
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| 	;
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| 	Mid is (Min+Max)/2, Next=Mid   % splitted domains overlap at Mid for floats
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| 	),
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| 	(
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| 	X::Min:Mid
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| 	;
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| 	X::Next:Max
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| 	% ;
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| 	% Min+1>Max,	% for floats only, to get X also bound
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| 	% X=Min		% or X=Max etc.
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| 	),
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| 	labeling
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|     pragma passive(Ph).
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| 
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| 	nonground(X) :- ground(X), !, fail.
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|         nonground(_).
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| 
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| 	domain(Kind) :- getval(domain,Kind).
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| 
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| % CHIP list shorthand for domain variables
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| % list must be known (end in the empty list)
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| 
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|  [X|L]::Dom <=> makedom([X|L],Dom).
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| 
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| 	makedom([],D) :- true.
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| 	makedom([X|L],D) :- 
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|                 nonvar(L),
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| 		X::D,
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| 		makedom(L,D).
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| 
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| 
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| % Consecutive integer domain ---------------------------------------------
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| % X::Min..Max - X is an integer between the numbers Min and Max (included)
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| % constraint is mapped to enumeration domain constraint
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|  X::Min..Max <=> 
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|         Min0 is Min, 
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|         (Min0=:=round(float(Min0)) -> Min1 is integer(Min0) ; Min1 is integer(Min0+1)),
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| 	Max1 is integer(Max),
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| 	interval(Min1,Max1,L), 
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| 	X::L.
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| 
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|  	interval(M,N,[M|Ns]):- 
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| 		M<N, 
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| 		!, 
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| 		M1 is M+1, 
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| 		interval(M1,N,Ns).
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| 	interval(N,N,[N]).
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| 
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| 
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| % Enumeration domain -----------------------------------------------------
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| 
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| % X::Dom - X must be a ground term in the ascending sorted ground list Dom
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|  X::[A|L] <=> list_to_ord_set([A|L],SL), SL\==[A|L] | X::SL.
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| % for number domain, allow arithmetic expressions in domain
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|  X::[A|L] <=> domain(number), member(X,[A|L]), \+ number(X) |
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| 		eval_list([A|L],L1),list_to_ord_set(L1,L2), X::L2.
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| 
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| 	eval_list([],[]).
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| 	eval_list([X|L1],[Y|L2]):-
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| 		Y is X,
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| 		eval_list(L1,L2).
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| 
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| % special cases
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|  X::[] <=> fail.				
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|  X::[Y] <=> X=Y.
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|  X::[A|L] <=> ground(X) | (member(X,[A|L]) -> true).
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| 
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| % intersection of domains for the same variable
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| % without pragma already_in_heads, needs already_in_store
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|  X::[A1|L1] \ X::[A2|L2] <=> 
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|     ord_intersection([A1|L1],[A2|L2],L),
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|     L \== [A2|L2]
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|     | 
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|     X::L.
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| 
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| % interaction with inequalities
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|  X::[A|L] \ X ne Y <=> integer(Y), remove(Y,[A|L],L1) | X::L1.
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|  X::[A|L] \ Y ne X <=> integer(Y), remove(Y,[A|L],L1) | X::L1.
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| 
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|  X::[A|L], Y le X ==> ground(Y), remove_lower(Y,[A|L],L1) | X::L1.
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|  X::[A|L], X le Y ==> ground(Y), remove_higher(Y,[A|L],L1) | X::L1.
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|  X::[A|L], Y lt X ==> ground(Y), remove_lower(Y,[A|L],L1),remove(Y,L1,L2) | X::L2.
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|  X::[A|L], X lt Y ==> ground(Y), remove_higher(Y,[A|L],L1),remove(Y,L1,L2) | X::L2.
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| 
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| % interaction with interval domain
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|  X::[A|L], X::Min:Max ==> remove_lower(Min,[A|L],L1),remove_higher(Max,L1,L2) | X::L2.
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| 
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| % propagation of bounds
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|  X le Y, Y::[A|L]   ==> var(X) | last([A|L],Max), X le Max.
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|  X le Y, X::[Min|_] ==> var(Y) | Min le Y.
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|  X lt Y, Y::[A|L]   ==> var(X) | last([A|L],Max), X lt Max.
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|  X lt Y, X::[Min|_] ==> var(Y) | Min lt Y.
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| 
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| % Interval domain ---------------------------------------------------------
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| % X::Min:Max - X must be a ground term between Min and Max (included)
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| % for number domain, allow for arithmetic expressions ind omain
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| % for integer domains, X::Min..Max should be used
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|  X::Min:Max <=> domain(number), \+ (number(Min),number(Max)) |
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| 		Min1 is Min, Max1 is Max, X::Min1:Max1.
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| % special cases
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|  X::Min:Min <=> X=Min.
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|  X::Min:Max <=> (domain(number) -> Min>Max ; Min@>Max) | fail.
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|  X::Min:Max <=> ground(X) | 
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| 		(domain(number) -> Min=<X,X=<Max ; Min@=<X,X@=<Max).
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| % intersection of domains for the same variable
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| % without pragma already_in_heads, needs already_in_store
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|  X::Min1:Max1 \ X::Min2:Max2 <=> maximum(Min1,Min2,Min),
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| 	                         minimum(Max1,Max2,Max),
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|                                  (Min \== Min2  ; Max \== Max2 ) |
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| 		X::Min:Max.
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| 
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| 	minimum(A,B,C):- (domain(number) -> A<B ; A@<B) -> A=C ; B=C.
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| 	maximum(A,B,C):- (domain(number) -> A<B ; A@<B) -> B=C ; A=C.
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| 
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| % interaction with inequalities
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|  X::Min:Max \ X ne Y <=> ground(Y),
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| 	(domain(number) -> (Y<Min;Y>Max) ; (Y@<Min;Y@>Max)) | true.
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|  X::Min:Max \ Y ne X <=> ground(Y),
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| 	(domain(number) -> (Y<Min;Y>Max) ; (Y@<Min;Y@>Max)) | true.
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|  X::Min1:Max \ Min2 le X <=> ground(Min2) , maximum(Min1,Min2,Min) | X::Min:Max.
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|  X::Min:Max1 \ X le Max2 <=> ground(Max2) , minimum(Max1,Max2,Max) | X::Min:Max.
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|  X::Min1:Max \ Min2 lt X <=> ground(Min2) , maximum(Min1,Min2,Min) |
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| 		X::Min:Max, X ne Min.
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|  X::Min:Max1 \ X lt Max2 <=> ground(Max2) , minimum(Max1,Max2,Max) |
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| 		X::Min:Max, X ne Max.
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| % propagation of bounds
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|  X le Y, Y::Min:Max ==> var(X) | X le Max.
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|  X le Y, X::Min:Max ==> var(Y) | Min le Y.
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|  X lt Y, Y::Min:Max ==> var(X) | X lt Max.
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|  X lt Y, X::Min:Max ==> var(Y) | Min lt Y.
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| 
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| 
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| 
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| % MULT/3 EXAMPLE EXTENSION ==================================================
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| % mult(X,Y,C) - integer X multiplied by integer Y gives the integer constant C.
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| 
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| constraints mult/3.
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| 
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| mult(X,Y,C) <=> ground(X) | (X=:=0 -> C=:=0 ; 0=:=C mod X, Y is C//X).
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| mult(Y,X,C) <=> ground(X) | (X=:=0 -> C=:=0 ; 0=:=C mod X, Y is C//X).
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| mult(X,Y,C), X::MinX:MaxX ==> 
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| 	%(Dom=MinX:MaxX -> true ; Dom=[MinX|L],last(L,MaxX)),
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| 	MinY is (C-1)//MaxX+1,
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|         MaxY is C//MinX,
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| 	Y::MinY:MaxY.
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| mult(Y,X,C), X::MinX:MaxX ==>
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| 	%(Dom=MinX:MaxX -> true ; Dom=[MinX|L],last(L,MaxX)),
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| 	MinY is (C-1)//MaxX+1,
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|         MaxY is C//MinX,
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| 	Y::MinY:MaxY.
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| 
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| /*
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| :- mult(X,Y,156),[X,Y]::2:156,X le Y.
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| 
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| X = X_g307
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| Y = Y_g331
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|  
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| Constraints:
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| (1) mult(X_g307, Y_g331, 156)
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| (7) Y_g331 :: 2 : 78
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| (8) X_g307 :: 2 : 78
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| (10) X_g307 le Y_g331
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| 
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| yes.
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| :- mult(X,Y,156),[X,Y]::2:156,X le Y,labeling.
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| 
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| X = 12
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| Y = 13     More? (;) 
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| 
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| X = 6
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| Y = 26     More? (;) 
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| 
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| X = 4
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| Y = 39     More? (;) 
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| 
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| X = 2
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| Y = 78     More? (;) 
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| 
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| X = 3
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| Y = 52     More? (;) 
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| 
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| no (more) solution.
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| */
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| 
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| 
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| 
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| 
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| % CHIP ELEMENT/3 ============================================================
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| % translated to "pair domains", a very powerful extension of usual domains
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| % this version does not work with arithmetic expressions!
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| 
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| element(I,VL,V):- length(VL,N),interval(1,N,IL),gen_pair(IL,VL,BL), I-V::BL.
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| 
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| 	gen_pair([],[],[]).
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| 	gen_pair([A|L1],[B|L2],[A-B|L3]):-
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| 		gen_pair(L1,L2,L3).
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| 
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| % special cases
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|  I-I::L <=> setof(X,member(X-X,L),L1), I::L1.
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|  I-V::L <=> ground(I) | setof(X,member(I-X,L),L1), V::L1.
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|  I-V::L <=> ground(V) | setof(X,member(X-V,L),L1), I::L1.
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| % intersections
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|  X::[A|L1], X-Y::L2 <=> intersect(I::[A|L1],I-V::L2,I-V::L3),
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| 			length(L2,N2),length(L3,N3),N2>N3 | X-Y::L3.
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|  Y::[A|L1], X-Y::L2 <=> intersect(V::[A|L1],I-V::L2,I-V::L3),
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| 			length(L2,N2),length(L3,N3),N2>N3 | X-Y::L3.
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|  X-Y::L1, Y-X::L2 <=> intersect(I-V::L1,V-I::L2,I-V::L3) | X-Y::L3.
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|  X-Y::L1, X-Y::L2 <=> intersect(I-V::L1,I-V::L2,I-V::L3) | X-Y::L3 pragma already_in_heads.
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| 
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|     intersect(A::L1,B::L2,C::L3):- setof(C,A^B^(member(A,L1),member(B,L2)),L3).
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| 
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| % inequalties with two common variables
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|  Y lt X, X-Y::L <=> A=R-S,setof(A,(member(A,L),R@< S),L1) | X-Y::L1.
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|  X lt Y, X-Y::L <=> A=R-S,setof(A,(member(A,L),S@< R),L1) | X-Y::L1.
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|  Y le X, X-Y::L <=> A=R-S,setof(A,(member(A,L),R@=<S),L1) | X-Y::L1.
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|  X le Y, X-Y::L <=> A=R-S,setof(A,(member(A,L),S@=<R),L1) | X-Y::L1.
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|  Y ne X, X-Y::L <=> A=R-S,setof(A,(member(A,L),R\==S),L1) | X-Y::L1.
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|  X ne Y, X-Y::L <=> A=R-S,setof(A,(member(A,L),S\==R),L1) | X-Y::L1.
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| % propagation between paired domains (path-consistency)
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| % X-Y::L1, Y-Z::L2 ==> intersect(A-B::L1,B-C::L2,A-C::L), X-Z::L.
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| % X-Y::L1, Z-Y::L2 ==> intersect(A-B::L1,C-B::L2,A-C::L), X-Z::L.
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| % X-Y::L1, X-Z::L2 ==> intersect(I-V::L1,I-W::L2,V-W::L), Y-Z::L.
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| % propagation to usual unary domains
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|  X-Y::L ==> A=R-S,setof(R,A^member(A,L),L1), X::L1,
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| 	          setof(S,A^member(A,L),L2), Y::L2.
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| 
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| 
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| 
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| % ATMOST/3 ===================================================================
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| 
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| atmost(N,List,V):-length(List,K),atmost(N,List,V,K).
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| 
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| constraints atmost/4.
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| 
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| atmost(N,List,V,K) <=> K=<N | true.
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| atmost(0,List,V,K) <=> (ground(V);ground(List)) | outof(V,List).
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| atmost(N,List,V,K) <=> K>N,ground(V),delete_ground(X,List,L1) |
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| 		(X==V -> N1 is N-1 ; N1=N),K1 is K-1, atmost(N1,L1,V,K1).
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| 
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| 	delete_ground(X,List,L1):- delete(X,List,L1),ground(X),!.
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| 
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| delete( X, [X|Xs], Xs).
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| delete( Y, [X|Xs], [X|Xt]) :-
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| 	delete( Y, Xs, Xt).
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| 
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| 
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| % ALLDISTINCT/1 ===============================================================
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| % uses ne/2 constraint
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| 
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| constraints alldistinct/1.
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| 
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| alldistinct([]) <=> true.
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| alldistinct([X]) <=> true.
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| alldistinct([X,Y]) <=> X ne Y.
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| alldistinct([A|L]) <=> delete_ground(X,[A|L],L1) | outof(X,L1),alldistinct(L1).
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| 
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| alldistinct([]).
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| alldistinct([X|L]):-
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| 	outof(X,L),
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| 	alldistinct(L).
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| 
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| outof(X,[]).
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| outof(X,[Y|L]):-
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| 	X ne Y,
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| 	outof(X,L).
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| 
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| constraints alldistinct1/2.
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| 		
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| alldistinct1(R,[]) <=> true.
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| alldistinct1(R,[X]), X::[A|L] <=> ground(R) | 
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| 			remove_list(R,[A|L],T), X::T.
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| alldistinct1(R,[X]) <=> (ground(R);ground(X)) | outof(X,R).	
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| alldistinct1(R,[A|L]) <=> ground(R),delete_ground(X,[A|L],L1) | 
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| 			(member(X,R) -> fail ; alldistinct1([X|R],L1)).
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| 
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| 
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| 
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| % CIRCUIT/1 =================================================================
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| 
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| % constraints circuit1/1, circuit/1.
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| % uses list domains and ne/2
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| 
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| 
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| % lazy version
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| 
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| circuit1(L):-length(L,N),N>1,circuit1(N,L).
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| 
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| circuit1(2,[2,1]).
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| circuit1(N,L):- N>2,
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| 		interval(1,N,D),
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| 		T=..[f|L],
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| 		domains1(1,D,L),
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| 		alldistinct1([],L),
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| 		no_subtours(N,1,T,[]).	
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| 
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| domains1(N,D,[]).
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| domains1(N,D,[X|L]):- 
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| 		remove(N,D,DX),
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| 		X::DX,
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| 		N1 is N+1,
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| 		domains1(N1,D,L).
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| 
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| no_subtours(0,N,L,R):- !.
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| no_subtours(K,N,L,R):- 
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| 	outof(N,R),
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| 	(var(N) -> freeze(N,no_subtours1(K,N,L,R)) ; no_subtours1(K,N,L,R)).
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| % no_subtours(K,N,T,R) \ no_subtours(K1,N,T,_) <=> K<K1 | true.
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| 
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| 	no_subtours1(K,N,L,R):- 
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| 		K>0,K1 is K-1,arg(N,L,A),no_subtours(K1,A,L,[N|R]).
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| 
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| 
 | |
| % eager version
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| 
 | |
| circuit(L):- length(L,N),N>1,circuit(N,L).
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| 
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| circuit(2,[2,1]).
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| %circuit(3,[2,3,1]).
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| %circuit(3,[3,1,2]).
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| circuit(N,L):- 	N>2,
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| 		interval(1,N,D),
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| 		T=..[f|L],
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| 		N1 is N-1,
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| 		domains(1,D,L,T,N1),
 | |
| 		alldistinct(L).		
 | |
| 
 | |
| domains(N,D,[],T,K).
 | |
| domains(N,D,[X|L],T,K):- 
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| 		remove(N,D,DX),
 | |
| 		X::DX,
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| 		N1 is N+1,
 | |
| 		no_subtours(K,N,T,[]),		% unfolded
 | |
| 		%no_subtours1(K,X,T,[N]),		
 | |
| 		domains(N1,D,L,T,K).
 | |
| 
 | |
| 
 | |
| 
 | |
| 
 | |
| % remove*/3 auxiliary predicates =============================================
 | |
| 
 | |
| remove(A,B,C):- 
 | |
| 	delete(A,B,C) -> true ; B=C.
 | |
| 
 | |
| remove_list(_,[],T):- !, T=[].
 | |
| remove_list([],S,T):- S=T.
 | |
| remove_list([X|R],[Y|S],T):- remove(X,[Y|S],S1),remove_list(R,S1,T).
 | |
| 
 | |
| remove_lower(_,[],L1):- !, L1=[].
 | |
| remove_lower(Min,[X|L],L1):-
 | |
| 	X@<Min,
 | |
| 	!,
 | |
| 	remove_lower(Min,L,L1).
 | |
| remove_lower(Min,[X|L],[X|L1]):-
 | |
| 	remove_lower(Min,L,L1).
 | |
| 
 | |
| remove_higher(_,[],L1):- !, L1=[].
 | |
| remove_higher(Max,[X|L],L1):-
 | |
| 	X@>Max,
 | |
| 	!,
 | |
| 	remove_higher(Max,L,L1).
 | |
| remove_higher(Max,[X|L],[X|L1]):-
 | |
| 	remove_higher(Max,L,L1).
 | |
| 
 | |
| 
 | |
| 
 | |
| % end of handler domain.chr =================================================
 | |
| % ===========================================================================
 | |
| 
 | |
| 
 |