35 lines
771 B
Plaintext
35 lines
771 B
Plaintext
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%
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%% simple constraint solver for inequalities between variables
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%% thom fruehwirth ECRC 950519, LMU 980207, 980311
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%%
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%% ported to hProlog by Tom Schrijvers
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:- module(leq,[]).
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:- use_module(library(chr)).
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:- constraints leq/2.
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reflexivity @ leq(X,X) <=> true.
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antisymmetry @ leq(X,Y), leq(Y,X) <=> X = Y.
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idempotence @ leq(X,Y) \ leq(X,Y) <=> true.
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transitivity @ leq(X,Y), leq(Y,Z) ==> leq(X,Z).
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t(N):-
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cputime(X),
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length(L,N),
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genleq(L,Last),
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L=[First|_],
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leq(Last,First),
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cputime( Now),
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Time is Now-X,
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write(N-Time), nl.
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genleq([Last],Last) :- ! .
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genleq([X,Y|Xs],Last):-
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leq(X,Y),
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genleq([Y|Xs],Last).
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cputime( Ts) :-
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statistics( runtime, [Tm,_]),
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Ts is Tm/1000.
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