conv.cpp
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/* -*- mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- */
/*
* Main authors:
* Guido Tack <tack@gecode.org>
* Christian Schulte <schulte@gecode.org>
* Gabor Szokoli <szokoli@gecode.org>
*
* Copyright:
* Guido Tack, 2004
* Christian Schulte, 2004
* Gabor Szokoli, 2004
*
* This file is part of Gecode, the generic constraint
* development environment:
* http://www.gecode.org
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
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* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
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* The above copyright notice and this permission notice shall be
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#include <gecode/set/convex.hh>
namespace Gecode { namespace Set { namespace Convex {
Actor*
Convex::copy(Space& home) {
return new (home) Convex(home,*this);
}
ExecStatus
Convex::propagate(Space& home, const ModEventDelta&) {
//I, drop ranges from UB that are shorter than cardMin
//II, add range LB.smallest to LB.largest to LB
//III, Drop ranges from UB that do not contain all elements of LB
//that is: range.min()>LB.smallest or range.max()<LB.largest
//This leaves only one range.
//II
if (x0.glbSize()>0) {
GECODE_ME_CHECK( x0.include(home,x0.glbMin(),x0.glbMax()) );
} else {
//If lower bound is empty, we can still constrain the cardinality
//maximum with the width of the longest range in UB.
//No need to do this if there is anything in LB because UB
//becomes a single range then.
LubRanges<SetView> ubRangeIt(x0);
unsigned int maxWidth = 0;
for (;ubRangeIt();++ubRangeIt) {
assert(ubRangeIt());
maxWidth = std::max(maxWidth, ubRangeIt.width());
}
GECODE_ME_CHECK( x0.cardMax(home,maxWidth) );
}
//I + III
Region r;
LubRanges<SetView> ubRangeIt(x0);
Iter::Ranges::Cache ubRangeItC(r,ubRangeIt);
for (; ubRangeItC(); ++ubRangeItC) {
if (ubRangeItC.width() < (unsigned int) x0.cardMin()
|| ubRangeItC.min() > x0.glbMin() //No need to test for empty lb.
|| ubRangeItC.max() < x0.glbMax()
) {
GECODE_ME_CHECK( x0.exclude(home,ubRangeItC.min(), ubRangeItC.max()) );
}
}
if (x0.assigned())
return home.ES_SUBSUMED(*this);
return ES_FIX;
}
}}}
// STATISTICS: set-prop
Gecode::Iter::Ranges::Cache
Range iterator cache
Definition ranges-cache.hpp:45
Gecode::Iter::Ranges::RangeListIter::max
int max(void) const
Return largest value of range.
Definition ranges-list.hpp:249
Gecode::Iter::Ranges::RangeListIter::width
unsigned int width(void) const
Return width of range (distance between minimum and maximum).
Definition ranges-list.hpp:253
Gecode::Iter::Ranges::RangeListIter::min
int min(void) const
Return smallest value of range.
Definition ranges-list.hpp:245
Gecode::Propagator::Space
friend class Space
Definition core.hpp:1066
Gecode::Region
Handle to region.
Definition region.hpp:55
Gecode::Set::Convex::Convex::copy
virtual Actor * copy(Space &home)
Copy propagator during cloning.
Definition conv.cpp:43
Gecode::Set::Convex::Convex::propagate
virtual ExecStatus propagate(Space &home, const ModEventDelta &med)
Perform propagation.
Definition conv.cpp:48
Gecode::Set::Convex::Convex::Convex
Convex(Space &home, Convex &p)
Constructor for cloning p.
Definition conv.hpp:52
Gecode::Set::LubRanges
Range iterator for the least upper bound.
Definition var-imp.hpp:317
Gecode::Set::LubRanges::width
unsigned int width(void) const
Return width of range (distance between minimum and maximum).
Gecode::UnaryPropagator< SetView, PC_SET_ANY >::x0
SetView x0
Definition pattern.hpp:58
convex.hh
Gecode::Space::ES_SUBSUMED
ExecStatus ES_SUBSUMED(Propagator &p)
Definition core.hpp:3563
Gecode::ModEventDelta
int ModEventDelta
Modification event deltas.
Definition core.hpp:89
GECODE_ME_CHECK
#define GECODE_ME_CHECK(me)
Check whether modification event me is failed, and forward failure.
Definition macros.hpp:52
Gecode::Set::Convex
Propagators for convexity.
Definition convex.hh:45
Gecode::Set
Finite integer sets.
Definition var-imp.hpp:137
Gecode
Gecode toplevel namespace
Gecode::ExecStatus
ExecStatus
Definition core.hpp:472
Gecode::ES_FIX
@ ES_FIX
Propagation has computed fixpoint.
Definition core.hpp:477