eqite.cpp
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/* -*- mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- */
/*
* Main authors:
* Christian Schulte <schulte@gecode.org>
*
* Copyright:
* Christian Schulte, 2015
*
* 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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* permit persons to whom the Software is furnished to do so, subject to
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#include <gecode/int/distinct.hh>
#include <algorithm>
namespace Gecode { namespace Int { namespace Distinct {
PropCost
EqIte::cost(const Space&, const ModEventDelta&) const {
return PropCost::binary(PropCost::HI);
}
Actor*
EqIte::copy(Space& home) {
return new (home) EqIte(home,*this);
}
ExecStatus
EqIte::propagate(Space& home, const ModEventDelta&) {
switch (rtest_eq_dom(x0,c0)) {
case RT_TRUE:
GECODE_ME_CHECK(x1.eq(home,c1));
return home.ES_SUBSUMED(*this);
case RT_FALSE:
GECODE_REWRITE(*this,(Rel::EqDom<IntView,IntView>
::post(home(*this),x0,x1)));
GECODE_NEVER;
case RT_MAYBE:
break;
default: GECODE_NEVER;
}
GECODE_ME_CHECK(x1.lq(home,std::max(x0.max(),c1)));
GECODE_ME_CHECK(x1.gq(home,std::min(x0.min(),c1)));
RelTest eq_then = rtest_eq_dom(x1,c1);
RelTest eq_else = rtest_eq_dom(x1,x0);
if ((eq_then == RT_FALSE) && (eq_else == RT_FALSE))
return ES_FAILED;
if (eq_then == RT_FALSE) {
// x1 and c1 are not equal
GECODE_ME_CHECK(x0.nq(home,c0));
if (eq_else == RT_TRUE)
return home.ES_SUBSUMED(*this);
else
GECODE_REWRITE(*this,
(Rel::EqDom<IntView,IntView>::post(home(*this),x0,x1)));
}
if (eq_else == RT_FALSE) {
// x0 and x1 are not equal
GECODE_ME_CHECK(x0.eq(home,c0));
GECODE_ME_CHECK(x1.eq(home,c1));
return home.ES_SUBSUMED(*this);
}
assert((eq_then != RT_TRUE) || (eq_else != RT_TRUE));
ViewRanges<IntView> r0(x0);
Iter::Ranges::Singleton r1(c1,c1);
Iter::Ranges::Union<ViewRanges<IntView>,
Iter::Ranges::Singleton > u(r0,r1);
GECODE_ME_CHECK(x1.inter_r(home,u,true));
return ES_FIX;
}
}}}
// STATISTICS: int-prop
Gecode::Actor
Base-class for both propagators and branchers.
Definition core.hpp:628
Gecode::BinaryPropagator< IntView, PC_INT_DOM >::x0
IntView x0
Definition pattern.hpp:87
Gecode::BinaryPropagator< IntView, PC_INT_DOM >::x1
IntView x1
Definition pattern.hpp:87
Gecode::Int::Distinct::EqIte::EqIte
EqIte(Space &home, EqIte &p)
Constructor for cloning p.
Definition eqite.hpp:43
Gecode::Int::Distinct::EqIte::copy
virtual Actor * copy(Space &home)
Copy propagator during cloning.
Definition eqite.cpp:46
Gecode::Int::Distinct::EqIte::cost
virtual PropCost cost(const Space &home, const ModEventDelta &med) const
Cost function (defined as high ternary).
Definition eqite.cpp:41
Gecode::Int::Distinct::EqIte::post
static ExecStatus post(Home home, IntView x0, IntView x1, int c0, int c1)
Post if-then-else propagator.
Definition eqite.hpp:49
Gecode::Int::Distinct::EqIte::c1
int c1
Definition distinct.hh:354
Gecode::Int::Distinct::EqIte::c0
int c0
The integer constant.
Definition distinct.hh:354
Gecode::Int::Distinct::EqIte::propagate
virtual ExecStatus propagate(Space &home, const ModEventDelta &med)
Perform propagation.
Definition eqite.cpp:51
Gecode::Int::Rel::EqDom
Binary domain consistent equality propagator.
Definition rel.hh:68
Gecode::Int::Rel::EqDom::post
static ExecStatus post(Home home, View0 x0, View1 x1)
Post domain consistent propagator .
Definition eq.hpp:176
Gecode::Int::ViewRanges
Range iterator for integer views.
Definition view.hpp:54
Gecode::Iter::Ranges::Singleton
Range iterator for singleton range.
Definition ranges-singleton.hpp:42
Gecode::Iter::Ranges::Union
Range iterator for computing union (binary).
Definition ranges-union.hpp:44
Gecode::PropCost::binary
static PropCost binary(PropCost::Mod m)
Two variables for modifier pcm.
Definition core.hpp:4809
Gecode::PropCost::HI
@ HI
Expensive.
Definition core.hpp:514
Gecode::Propagator::Space
friend class Space
Definition core.hpp:1066
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_REWRITE
#define GECODE_REWRITE(prop, post)
Rewrite propagator by executing post function.
Definition macros.hpp:116
distinct.hh
Gecode::Int::Distinct
Distinct propagators
Gecode::Int
Finite domain integers.
Gecode::Int::rtest_eq_dom
RelTest rtest_eq_dom(VX x, VY y)
Test whether views x and y are equal (use full domain information).
Definition rel-test.hpp:65
Gecode::Int::RelTest
RelTest
Result of testing relation.
Definition view.hpp:1734
Gecode::Int::RT_TRUE
@ RT_TRUE
Relation does hold.
Definition view.hpp:1737
Gecode::Int::RT_MAYBE
@ RT_MAYBE
Relation may hold or not.
Definition view.hpp:1736
Gecode::Int::RT_FALSE
@ RT_FALSE
Relation does not hold.
Definition view.hpp:1735
Gecode
Gecode toplevel namespace
Gecode::ExecStatus
ExecStatus
Definition core.hpp:472
Gecode::ES_FIX
@ ES_FIX
Propagation has computed fixpoint.
Definition core.hpp:477
Gecode::ES_FAILED
@ ES_FAILED
Execution has resulted in failure.
Definition core.hpp:474
GECODE_NEVER
#define GECODE_NEVER
Assert that this command is never executed.
Definition macros.hpp:56