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/* -*- mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- */
/*
* Main authors:
* Christian Schulte <schulte@gecode.org>
*
* Copyright:
* Christian Schulte, 2011
*
* 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/rel.hh>
#include <gecode/int/distinct.hh>
namespace Gecode { namespace Int { namespace NValues {
template<class VY>
forceinline
EqInt<VY>::EqInt(Home home, ValSet& vs, ViewArray<IntView>& x, VY y)
: IntBase<VY>(home,vs,x,y) {
home.notice(*this, AP_WEAKLY);
}
template<class VY>
inline ExecStatus
EqInt<VY>::post(Home home, ViewArray<IntView>& x, VY y) {
if (x.size() == 0) {
GECODE_ME_CHECK(y.eq(home,0));
return ES_OK;
}
x.unique();
if (x.size() == 1) {
GECODE_ME_CHECK(y.eq(home,1));
return ES_OK;
}
GECODE_ME_CHECK(y.gq(home,1));
GECODE_ME_CHECK(y.lq(home,x.size()));
if (y.max() == 1) {
assert(y.assigned());
return Rel::NaryEqDom<IntView>::post(home,x);
}
if (y.min() == x.size()) {
assert(y.assigned());
return Distinct::Dom<IntView>::post(home,x);
}
// Eliminate assigned views and store them into the value set
ValSet vs;
int n = x.size();
for (int i=n; i--; )
if (x[i].assigned()) {
vs.add(home, x[i].val());
x[i] = x[--n];
}
GECODE_ME_CHECK(y.gq(home,vs.size()));
GECODE_ME_CHECK(y.lq(home,n + vs.size()));
if (n == 0) {
assert(y.val() == vs.size());
return ES_OK;
}
x.size(n);
(void) new (home) EqInt<VY>(home, vs, x, y);
return ES_OK;
}
template<class VY>
forceinline
EqInt<VY>::EqInt(Space& home, EqInt<VY>& p)
: IntBase<VY>(home, p) {}
template<class VY>
Propagator*
EqInt<VY>::copy(Space& home) {
return new (home) EqInt<VY>(home, *this);
}
template<class VY>
forceinline size_t
EqInt<VY>::dispose(Space& home) {
home.ignore(*this, AP_WEAKLY);
(void) IntBase<VY>::dispose(home);
return sizeof(*this);
}
template<class VY>
ExecStatus
EqInt<VY>::propagate(Space& home, const ModEventDelta& med) {
// Add assigned views to value set
if (IntView::me(med) == ME_INT_VAL)
add(home);
GECODE_ME_CHECK(y.gq(home, vs.size()));
GECODE_ME_CHECK(y.lq(home, x.size() + vs.size()));
if (x.size() == 0)
return home.ES_SUBSUMED(*this);
// All values must be in the value set
if (y.max() == vs.size())
return all_in_valset(home);
// Compute positions of disjoint views and eliminate subsumed views
Region r;
int* dis; int n_dis;
disjoint(home,r,dis,n_dis);
// The number might have changed due to elimination of subsumed views
GECODE_ME_CHECK(y.lq(home, x.size() + vs.size()));
if (x.size() == 0) {
assert(y.val() == vs.size());
return home.ES_SUBSUMED(*this);
}
GECODE_ES_CHECK(prune_upper(home,g));
// No lower bound pruning possible
if (n_dis == 0)
return ES_NOFIX;
// Only if the propagator is at fixpoint here, continue with
// propagating the lower bound
if (IntView::me(Propagator::modeventdelta()) != ME_INT_NONE)
return ES_NOFIX;
// Do lower bound-based pruning
GECODE_ES_CHECK(prune_lower(home,dis,n_dis));
return ES_NOFIX;
}
}}}
// STATISTICS: int-prop