int-gq.hpp
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/* -*- mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- */
/*
* Main authors:
* Christian Schulte <schulte@gecode.org>
*
* Copyright:
* Christian Schulte, 2006
*
* 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
* "Software"), to deal in the Software without restriction, including
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* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
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*
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namespace Gecode { namespace Int { namespace Count {
template<class VX, class VY>
forceinline
GqInt<VX,VY>::GqInt(Home home, ViewArray<VX>& x, int n_s, VY y, int c)
: IntBase<VX,VY>(home,x,n_s,y,c) {}
template<class VX, class VY>
ExecStatus
GqInt<VX,VY>::post(Home home, ViewArray<VX>& x, VY y, int c) {
// Eliminate decided views
int n_x = x.size();
for (int i=n_x; i--; )
switch (holds(x[i],y)) {
case RT_FALSE:
x[i] = x[--n_x]; break;
case RT_TRUE:
x[i] = x[--n_x]; c--; break;
case RT_MAYBE:
break;
default:
GECODE_NEVER;
}
x.size(n_x);
// RHS too large
if (n_x < c)
return ES_FAILED;
// Whatever the x[i] take for values, the inequality is subsumed
if (c <= 0)
return ES_OK;
// All views must be equal
if (c == n_x)
return post_true(home,x,y);
(void) new (home) GqInt<VX,VY>(home,x,c+1,y,c);
return ES_OK;
}
template<class VX, class VY>
forceinline
GqInt<VX,VY>::GqInt(Space& home, GqInt<VX,VY>& p)
: IntBase<VX,VY>(home,p) {}
template<class VX, class VY>
Actor*
GqInt<VX,VY>::copy(Space& home) {
return new (home) GqInt<VX,VY>(home,*this);
}
template<class VX, class VY>
ExecStatus
GqInt<VX,VY>::propagate(Space& home, const ModEventDelta&) {
// Eliminate decided views from subscribed views
int n_x = x.size();
for (int i=n_s; i--; )
switch (holds(x[i],y)) {
case RT_FALSE:
x[i].cancel(home,*this,PC_INT_DOM);
x[i]=x[--n_s]; x[n_s]=x[--n_x];
break;
case RT_TRUE:
x[i].cancel(home,*this,PC_INT_DOM);
x[i]=x[--n_s]; x[n_s]=x[--n_x]; c--;
break;
case RT_MAYBE:
break;
default:
GECODE_NEVER;
}
x.size(n_x);
if (n_x < c)
return ES_FAILED;
if (c <= 0)
return home.ES_SUBSUMED(*this);
// Eliminate decided views from unsubscribed views
for (int i=n_x; i-- > n_s; )
switch (holds(x[i],y)) {
case RT_FALSE: x[i]=x[--n_x]; break;
case RT_TRUE: x[i]=x[--n_x]; c--; break;
case RT_MAYBE: break;
default: GECODE_NEVER;
}
x.size(n_x);
if (n_x < c)
return ES_FAILED;
if (c <= 0)
return home.ES_SUBSUMED(*this);
if (c == n_x) {
// All views must be equal
GECODE_ES_CHECK(post_true(home,x,y));
return home.ES_SUBSUMED(*this);
}
// Now, there must be new subscriptions from x[n_s] up to x[c+1]
while (n_s <= c)
x[n_s++].subscribe(home,*this,PC_INT_DOM,false);
return ES_FIX;
}
}}}
// STATISTICS: int-prop
Gecode::Actor
Base-class for both propagators and branchers.
Definition core.hpp:628
Gecode::Home
Home class for posting propagators
Definition core.hpp:856
Gecode::Int::Count::GqInt::GqInt
GqInt(Space &home, GqInt &p)
Constructor for cloning p.
Definition int-gq.hpp:73
Gecode::Int::Count::GqInt::post
static ExecStatus post(Home home, ViewArray< VX > &x, VY y, int c)
Post propagator for .
Definition int-gq.hpp:43
Gecode::Int::Count::GqInt::propagate
virtual ExecStatus propagate(Space &home, const ModEventDelta &med)
Perform propagation.
Definition int-gq.hpp:84
Gecode::Int::Count::GqInt::copy
virtual Actor * copy(Space &home)
Create copy during cloning.
Definition int-gq.hpp:78
Gecode::Int::Count::IntBase::IntBase
IntBase(Space &home, IntBase &p)
Constructor for cloning p.
Definition int-base.hpp:62
Gecode::Int::Count::IntBase::n_s
int n_s
Views from x[0] ... x[n_s-1] have subscriptions.
Definition count.hh:143
Gecode::Int::Count::IntBase::x
ViewArray< VX > x
Views still to count.
Definition count.hh:141
Gecode::Int::Count::IntBase::c
int c
Number of views which are equal and have been eliminated.
Definition count.hh:147
Gecode::Int::Count::IntBase::y
VY y
View to compare to.
Definition count.hh:145
Gecode::Propagator::Space
friend class Space
Definition core.hpp:1066
Gecode::ViewArray
View arrays.
Definition array.hpp:253
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_ES_CHECK
#define GECODE_ES_CHECK(es)
Check whether execution status es is failed or subsumed, and forward failure or subsumption.
Definition macros.hpp:91
Gecode::Int::Count
Counting propagators.
Gecode::Int::Count::post_true
ExecStatus post_true(Home home, ViewArray< VX > &x, VX y)
Post that all views in x are equal to y.
Definition rel.hpp:237
Gecode::Int::Count::holds
RelTest holds(VX x, VX y)
Test whether x and y are equal.
Definition rel.hpp:145
Gecode::Int
Finite domain integers.
Gecode::Int::PC_INT_DOM
const Gecode::PropCond PC_INT_DOM
Propagate when domain changes.
Definition var-type.hpp:100
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_OK
@ ES_OK
Execution is okay.
Definition core.hpp:476
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
forceinline
#define forceinline
Definition config.hpp:187
GECODE_NEVER
#define GECODE_NEVER
Assert that this command is never executed.
Definition macros.hpp:56