divmod.hpp
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/* -*- mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- */
/*
* Main authors:
* Guido Tack <tack@gecode.org>
*
* Copyright:
* Guido Tack, 2008
*
* 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
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* 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
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
*/
#include <gecode/int/linear.hh>
namespace Gecode { namespace Int { namespace Arithmetic {
/*
* Positive bounds consistent division
*
*/
template<class VA, class VB, class VC>
forceinline
DivPlusBnd<VA,VB,VC>::DivPlusBnd(Home home, VA x0, VB x1, VC x2)
: MixTernaryPropagator<VA,PC_INT_BND,VB,PC_INT_BND,VC,PC_INT_BND>
(home,x0,x1,x2) {}
template<class VA, class VB, class VC>
forceinline
DivPlusBnd<VA,VB,VC>::DivPlusBnd(Space& home, DivPlusBnd<VA,VB,VC>& p)
: MixTernaryPropagator<VA,PC_INT_BND,VB,PC_INT_BND,VC,PC_INT_BND>
(home,p) {}
template<class VA, class VB, class VC>
Actor*
DivPlusBnd<VA,VB,VC>::copy(Space& home) {
return new (home) DivPlusBnd<VA,VB,VC>(home,*this);
}
template<class VA, class VB, class VC>
ExecStatus
DivPlusBnd<VA,VB,VC>::propagate(Space& home, const ModEventDelta&) {
assert(pos(x0) && pos(x1) && !neg(x2));
bool mod;
do {
mod = false;
GECODE_ME_CHECK_MODIFIED(mod,x2.lq(home,
floor_div_pp(x0.max(),x1.min())));
GECODE_ME_CHECK_MODIFIED(mod,x2.gq(home,
floor_div_px(x0.min(),x1.max())));
GECODE_ME_CHECK_MODIFIED(mod,x0.le(home,mll(x1.max(),ill(x2.max()))));
GECODE_ME_CHECK_MODIFIED(mod,x0.gq(home,mll(x1.min(),x2.min())));
if (x2.min() > 0) {
GECODE_ME_CHECK_MODIFIED(mod,
x1.lq(home,floor_div_pp(x0.max(),x2.min())));
}
GECODE_ME_CHECK_MODIFIED(mod,x1.gq(home,ceil_div_pp(ll(x0.min()),
ill(x2.max()))));
} while (mod);
return x0.assigned() && x1.assigned() ?
home.ES_SUBSUMED(*this) : ES_FIX;
}
template<class VA, class VB, class VC>
forceinline ExecStatus
DivPlusBnd<VA,VB,VC>::post(Home home, VA x0, VB x1, VC x2) {
GECODE_ME_CHECK(x0.gr(home,0));
GECODE_ME_CHECK(x1.gr(home,0));
GECODE_ME_CHECK(x2.gq(home,floor_div_pp(x0.min(),x1.max())));
(void) new (home) DivPlusBnd<VA,VB,VC>(home,x0,x1,x2);
return ES_OK;
}
/*
* Bounds consistent division
*
*/
template<class View>
forceinline
DivBnd<View>::DivBnd(Home home, View x0, View x1, View x2)
: TernaryPropagator<View,PC_INT_BND>(home,x0,x1,x2) {}
template<class View>
forceinline
DivBnd<View>::DivBnd(Space& home, DivBnd<View>& p)
: TernaryPropagator<View,PC_INT_BND>(home,p) {}
template<class View>
Actor*
DivBnd<View>::copy(Space& home) {
return new (home) DivBnd<View>(home,*this);
}
template<class View>
ExecStatus
DivBnd<View>::propagate(Space& home, const ModEventDelta&) {
if (pos(x1)) {
if (pos(x2) || pos(x0)) goto rewrite_ppp;
if (neg(x2) || neg(x0)) goto rewrite_npn;
goto prop_xpx;
}
if (neg(x1)) {
if (neg(x2) || pos(x0)) goto rewrite_pnn;
if (pos(x2) || neg(x0)) goto rewrite_nnp;
goto prop_xnx;
}
if (pos(x2)) {
if (pos(x0)) goto rewrite_ppp;
if (neg(x0)) goto rewrite_nnp;
goto prop_xxp;
}
if (neg(x2)) {
if (pos(x0)) goto rewrite_pnn;
if (neg(x0)) goto rewrite_npn;
goto prop_xxn;
}
assert(any(x1) && any(x2));
GECODE_ME_CHECK(x0.lq(home,std::max(mll(x1.max(),ill(x2.max()))-1,
mll(x1.min(),dll(x2.min()))-1)));
GECODE_ME_CHECK(x0.gq(home,std::min(mll(x1.min(),ill(x2.max())),
mll(x1.max(),dll(x2.min())))));
return ES_NOFIX;
prop_xxp:
assert(any(x0) && any(x1) && pos(x2));
GECODE_ME_CHECK(x0.le(home, mll(x1.max(),ill(x2.max()))));
GECODE_ME_CHECK(x0.gq(home, mll(x1.min(),ill(x2.max()))));
if (pos(x0)) goto rewrite_ppp;
if (neg(x0)) goto rewrite_nnp;
GECODE_ME_CHECK(x1.lq(home,floor_div_pp(x0.max(),x2.min())));
GECODE_ME_CHECK(x1.gq(home,ceil_div_xp(x0.min(),x2.min())));
if (x0.assigned() && x1.assigned())
goto subsumed;
return ES_NOFIX;
prop_xpx:
assert(any(x0) && pos(x1) && any(x2));
GECODE_ME_CHECK(x0.le(home, mll(x1.max(),ill(x2.max()))));
GECODE_ME_CHECK(x0.gq(home, mll(x1.max(),dll(x2.min()))));
if (pos(x0)) goto rewrite_ppp;
if (neg(x0)) goto rewrite_npn;
GECODE_ME_CHECK(x2.lq(home,floor_div_xp(x0.max(),x1.min())));
GECODE_ME_CHECK(x2.gq(home,floor_div_xp(x0.min(),x1.min())));
if (x0.assigned() && x1.assigned())
goto subsumed;
return ES_NOFIX;
prop_xxn:
assert(any(x0) && any(x1) && neg(x2));
GECODE_ME_CHECK(x0.lq(home, mll(x1.min(),dll(x2.min()))));
GECODE_ME_CHECK(x0.gq(home, mll(x1.max(),dll(x2.min()))));
if (pos(x0)) goto rewrite_pnn;
if (neg(x0)) goto rewrite_npn;
if (x2.max() != -1)
GECODE_ME_CHECK(x1.lq(home,ceil_div_xx(ll(x0.min()),ill(x2.max()))));
if (x2.max() != -1)
GECODE_ME_CHECK(x1.gq(home,ceil_div_xx(ll(x0.max()),ill(x2.max()))));
if (x0.assigned() && x1.assigned())
goto subsumed;
return ES_NOFIX;
prop_xnx:
assert(any(x0) && neg(x1) && any(x2));
GECODE_ME_CHECK(x0.lq(home, mll(x1.min(),dll(x2.min()))));
GECODE_ME_CHECK(x0.gq(home, mll(x1.min(),ill(x2.max()))));
if (pos(x0)) goto rewrite_pnn;
if (neg(x0)) goto rewrite_nnp;
GECODE_ME_CHECK(x2.lq(home,floor_div_xx(x0.min(),x1.max())));
GECODE_ME_CHECK(x2.gq(home,floor_div_xx(x0.max(),x1.max())));
if (x0.assigned() && x1.assigned())
goto subsumed;
return ES_NOFIX;
rewrite_ppp:
GECODE_REWRITE(*this,(DivPlusBnd<IntView,IntView,IntView>
::post(home(*this),x0,x1,x2)));
rewrite_nnp:
GECODE_REWRITE(*this,(DivPlusBnd<MinusView,MinusView,IntView>
::post(home(*this),MinusView(x0),MinusView(x1),x2)));
rewrite_pnn:
GECODE_REWRITE(*this,(DivPlusBnd<IntView,MinusView,MinusView>
::post(home(*this),x0,MinusView(x1),MinusView(x2))));
rewrite_npn:
GECODE_REWRITE(*this,(DivPlusBnd<MinusView,IntView,MinusView>
::post(home(*this),MinusView(x0),x1,MinusView(x2))));
subsumed:
assert(x0.assigned() && x1.assigned());
int result = std::abs(x0.val()) / std::abs(x1.val());
if (x0.val()/x1.val() < 0)
result = -result;
GECODE_ME_CHECK(x2.eq(home,result));
return home.ES_SUBSUMED(*this);
}
template<class View>
ExecStatus
DivBnd<View>::post(Home home, View x0, View x1, View x2) {
GECODE_ME_CHECK(x1.nq(home, 0));
if (pos(x0)) {
if (pos(x1) || pos(x2)) goto post_ppp;
if (neg(x1) || neg(x2)) goto post_pnn;
} else if (neg(x0)) {
if (neg(x1) || pos(x2)) goto post_nnp;
if (pos(x1) || neg(x2)) goto post_npn;
} else if (pos(x1)) {
if (pos(x2)) goto post_ppp;
if (neg(x2)) goto post_npn;
} else if (neg(x1)) {
if (pos(x2)) goto post_nnp;
if (neg(x2)) goto post_pnn;
}
(void) new (home) DivBnd<View>(home,x0,x1,x2);
return ES_OK;
post_ppp:
return DivPlusBnd<IntView,IntView,IntView>
::post(home,x0,x1,x2);
post_nnp:
return DivPlusBnd<MinusView,MinusView,IntView>
::post(home,MinusView(x0),MinusView(x1),x2);
post_pnn:
return DivPlusBnd<IntView,MinusView,MinusView>
::post(home,x0,MinusView(x1),MinusView(x2));
post_npn:
return DivPlusBnd<MinusView,IntView,MinusView>
::post(home,MinusView(x0),x1,MinusView(x2));
}
/*
* Propagator for x0 != 0 /\ (x1 != 0 => x0*x1>0) /\ abs(x1)<abs(x0)
*
*/
template<class View>
forceinline
DivMod<View>::DivMod(Home home, View x0, View x1, View x2)
: TernaryPropagator<View,PC_INT_BND>(home,x0,x1,x2) {}
template<class View>
forceinline ExecStatus
DivMod<View>::post(Home home, View x0, View x1, View x2) {
GECODE_ME_CHECK(x1.nq(home,0));
(void) new (home) DivMod<View>(home,x0,x1,x2);
return ES_OK;
}
template<class View>
forceinline
DivMod<View>::DivMod(Space& home, DivMod<View>& p)
: TernaryPropagator<View,PC_INT_BND>(home,p) {}
template<class View>
Actor*
DivMod<View>::copy(Space& home) {
return new (home) DivMod<View>(home,*this);
}
template<class View>
ExecStatus
DivMod<View>::propagate(Space& home, const ModEventDelta&) {
bool signIsSame;
do {
signIsSame = true;
// The sign of x0 and x2 is the same
if (x0.min() >= 0) {
GECODE_ME_CHECK(x2.gq(home, 0));
} else if (x0.max() <= 0) {
GECODE_ME_CHECK(x2.lq(home, 0));
} else if (x2.min() > 0) {
GECODE_ME_CHECK(x0.gq(home, 0));
} else if (x2.max() < 0) {
GECODE_ME_CHECK(x0.lq(home, 0));
} else {
signIsSame = false;
}
// abs(x2) is less than abs(x1)
int x1max = std::max(x1.max(),std::max(-x1.max(),
std::max(x1.min(),-x1.min())));
GECODE_ME_CHECK(x2.le(home, x1max));
GECODE_ME_CHECK(x2.gr(home, -x1max));
int x2absmin = any(x2) ? 0 : (pos(x2) ? x2.min() : -x2.max());
Iter::Ranges::Singleton sr(-x2absmin,x2absmin);
GECODE_ME_CHECK(x1.minus_r(home,sr,false));
} while (!signIsSame &&
(x0.min() > 0 || x0.max() < 0 || x2.min() > 0 || x2.max() < 0));
if (signIsSame) {
int x2max = std::max(x2.max(),std::max(-x2.max(),
std::max(x2.min(),-x2.min())));
int x1absmin = any(x1) ? 0 : (pos(x1) ? x1.min() : -x1.max());
if (x2max < x1absmin)
return home.ES_SUBSUMED(*this);
}
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::Arithmetic::DivBnd::copy
virtual Actor * copy(Space &home)
Copy propagator during cloning.
Definition divmod.hpp:112
Gecode::Int::Arithmetic::DivBnd::DivBnd
DivBnd(Space &home, DivBnd< View > &p)
Constructor for cloning p.
Definition divmod.hpp:107
Gecode::Int::Arithmetic::DivBnd::post
static ExecStatus post(Home home, View x0, View x1, View x2)
Post propagator (rounding towards 0).
Definition divmod.hpp:235
Gecode::Int::Arithmetic::DivBnd::propagate
virtual ExecStatus propagate(Space &home, const ModEventDelta &med)
Perform propagation.
Definition divmod.hpp:118
Gecode::Int::Arithmetic::DivMod::post
static ExecStatus post(Home home, View x0, View x1, View x2)
Post propagator .
Definition divmod.hpp:280
Gecode::Int::Arithmetic::DivMod::copy
virtual Actor * copy(Space &home)
Copy propagator during cloning.
Definition divmod.hpp:293
Gecode::Int::Arithmetic::DivMod::DivMod
DivMod(Space &home, DivMod< View > &p)
Constructor for cloning p.
Definition divmod.hpp:288
Gecode::Int::Arithmetic::DivMod::propagate
virtual ExecStatus propagate(Space &home, const ModEventDelta &med)
Perform propagation.
Definition divmod.hpp:299
Gecode::Int::Arithmetic::DivPlusBnd
Bounds consistent positive division propagator.
Definition arithmetic.hh:778
Gecode::Int::Arithmetic::DivPlusBnd::post
static ExecStatus post(Home home, VA x0, VB x1, VC x2)
Post propagator (rounding towards 0).
Definition divmod.hpp:87
Gecode::Int::Arithmetic::DivPlusBnd::copy
virtual Actor * copy(Space &home)
Copy propagator during cloning.
Definition divmod.hpp:57
Gecode::Int::Arithmetic::DivPlusBnd::DivPlusBnd
DivPlusBnd(Home home, VA x0, VB x1, VC x2)
Constructor for posting.
Definition divmod.hpp:45
Gecode::Int::Arithmetic::DivPlusBnd::propagate
virtual ExecStatus propagate(Space &home, const ModEventDelta &med)
Perform propagation.
Definition divmod.hpp:63
Gecode::Int::MinusView
Minus integer view.
Definition view.hpp:282
Gecode::Iter::Ranges::Singleton
Range iterator for singleton range.
Definition ranges-singleton.hpp:42
Gecode::MixTernaryPropagator< VA, PC_INT_BND, VB, PC_INT_BND, VC, PC_INT_BND >::x0
VA x0
Definition pattern.hpp:240
Gecode::MixTernaryPropagator< VA, PC_INT_BND, VB, PC_INT_BND, VC, PC_INT_BND >::x1
VB x1
Definition pattern.hpp:242
Gecode::MixTernaryPropagator< VA, PC_INT_BND, VB, PC_INT_BND, VC, PC_INT_BND >::x2
VC x2
Definition pattern.hpp:244
Gecode::MixTernaryPropagator< VA, PC_INT_BND, VB, PC_INT_BND, VC, PC_INT_BND >::MixTernaryPropagator
MixTernaryPropagator(Space &home, MixTernaryPropagator &p)
Definition pattern.hpp:661
Gecode::Propagator::Space
friend class Space
Definition core.hpp:1066
Gecode::TernaryPropagator< View, PC_INT_BND >::x2
View x2
Definition pattern.hpp:116
Gecode::TernaryPropagator< View, PC_INT_BND >::x1
View x1
Definition pattern.hpp:116
Gecode::TernaryPropagator< View, PC_INT_BND >::x0
View x0
Definition pattern.hpp:116
Gecode::TernaryPropagator< View, PC_INT_BND >::TernaryPropagator
TernaryPropagator(Space &home, TernaryPropagator &p)
Gecode::View
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
GECODE_ME_CHECK_MODIFIED
#define GECODE_ME_CHECK_MODIFIED(modified, me)
Check whether me is failed or modified, and forward failure.
Definition macros.hpp:64
linear.hh
Gecode::Int::Arithmetic
Numerical (arithmetic) propagators.
Gecode::Int::Arithmetic::dll
long long int dll(int x)
Decrement x by one.
Definition mult.hpp:63
Gecode::Int::Arithmetic::pos
bool pos(const View &x)
Test whether x is postive.
Definition mult.hpp:70
Gecode::Int::Arithmetic::any
bool any(const View &x)
Test whether x is neither positive nor negative.
Definition mult.hpp:82
Gecode::Int::Arithmetic::mll
long long int mll(long long int x, long long int y)
Multiply x and \y.
Definition mult.hpp:48
Gecode::Int::Arithmetic::ill
long long int ill(int x)
Increment x by one.
Definition mult.hpp:58
Gecode::Int::Arithmetic::neg
bool neg(const View &x)
Test whether x is negative.
Definition mult.hpp:76
Gecode::Int::Arithmetic::ll
long long int ll(int x)
Cast x into a long long int.
Definition mult.hpp:53
Gecode::Int
Finite domain integers.
Gecode::Int::ceil_div_pp
IntType ceil_div_pp(IntType x, IntType y)
Compute where x and y are non-negative.
Definition div.hpp:38
Gecode::Int::PC_INT_BND
const Gecode::PropCond PC_INT_BND
Propagate when minimum or maximum of a view changes.
Definition var-type.hpp:91
Gecode::Int::ceil_div_xp
IntType ceil_div_xp(IntType x, IntType y)
Compute where y is non-negative.
Definition div.hpp:69
Gecode::Int::floor_div_xp
IntType floor_div_xp(IntType x, IntType y)
Compute where y is non-negative.
Definition div.hpp:75
Gecode::Int::floor_div_xx
IntType floor_div_xx(IntType x, IntType y)
Compute .
Definition div.hpp:87
Gecode::Int::floor_div_pp
IntType floor_div_pp(IntType x, IntType y)
Compute where x and y are non-negative.
Definition div.hpp:49
Gecode::Int::ceil_div_xx
IntType ceil_div_xx(IntType x, IntType y)
Compute .
Definition div.hpp:82
Gecode::Int::floor_div_px
IntType floor_div_px(IntType x, IntType y)
Compute where x is non-negative.
Definition div.hpp:62
Gecode
Gecode toplevel namespace
Gecode::mod
void mod(Home home, IntVar x0, IntVar x1, IntVar x2, IntPropLevel ipl=IPL_DEF)
Post propagator for .
Definition arithmetic.cpp:360
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_NOFIX
@ ES_NOFIX
Propagation has not computed fixpoint.
Definition core.hpp:475
forceinline
#define forceinline
Definition config.hpp:187