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int-eq.hpp
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7  * Christian Schulte, 2011
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33 
34 #include <gecode/int/rel.hh>
35 #include <gecode/int/distinct.hh>
36 
37 namespace Gecode { namespace Int { namespace NValues {
38 
39  template<class VY>
42  : IntBase<VY>(home,vs,x,y) {
43  home.notice(*this, AP_WEAKLY);
44  }
45 
46  template<class VY>
47  inline ExecStatus
49  if (x.size() == 0) {
50  GECODE_ME_CHECK(y.eq(home,0));
51  return ES_OK;
52  }
53 
54  x.unique();
55 
56  if (x.size() == 1) {
57  GECODE_ME_CHECK(y.eq(home,1));
58  return ES_OK;
59  }
60 
61  GECODE_ME_CHECK(y.gq(home,1));
62  GECODE_ME_CHECK(y.lq(home,x.size()));
63 
64  if (y.max() == 1) {
65  assert(y.assigned());
66  return Rel::NaryEqDom<IntView>::post(home,x);
67  }
68 
69  if (y.min() == x.size()) {
70  assert(y.assigned());
71  return Distinct::Dom<IntView>::post(home,x);
72  }
73 
74  // Eliminate assigned views and store them into the value set
75  ValSet vs;
76  int n = x.size();
77  for (int i=n; i--; )
78  if (x[i].assigned()) {
79  vs.add(home, x[i].val());
80  x[i] = x[--n];
81  }
82 
83  GECODE_ME_CHECK(y.gq(home,vs.size()));
84  GECODE_ME_CHECK(y.lq(home,n + vs.size()));
85 
86  if (n == 0) {
87  assert(y.val() == vs.size());
88  return ES_OK;
89  }
90  x.size(n);
91  (void) new (home) EqInt<VY>(home, vs, x, y);
92  return ES_OK;
93  }
94 
95  template<class VY>
98  : IntBase<VY>(home, p) {}
99 
100  template<class VY>
101  Propagator*
103  return new (home) EqInt<VY>(home, *this);
104  }
105 
106  template<class VY>
107  forceinline size_t
109  home.ignore(*this, AP_WEAKLY);
110  (void) IntBase<VY>::dispose(home);
111  return sizeof(*this);
112  }
113 
114  template<class VY>
115  ExecStatus
117  // Add assigned views to value set
118  if (IntView::me(med) == ME_INT_VAL)
119  add(home);
120 
121  GECODE_ME_CHECK(y.gq(home, vs.size()));
122  GECODE_ME_CHECK(y.lq(home, x.size() + vs.size()));
123 
124  if (x.size() == 0)
125  return home.ES_SUBSUMED(*this);
126 
127  // All values must be in the value set
128  if (y.max() == vs.size())
129  return all_in_valset(home);
130 
131  // Compute positions of disjoint views and eliminate subsumed views
132  Region r;
133  int* dis; int n_dis;
134  disjoint(home,r,dis,n_dis);
135 
136  // The number might have changed due to elimination of subsumed views
137  GECODE_ME_CHECK(y.lq(home, x.size() + vs.size()));
138 
139  if (x.size() == 0) {
140  assert(y.val() == vs.size());
141  return home.ES_SUBSUMED(*this);
142  }
143 
144  GECODE_ES_CHECK(prune_upper(home,g));
145 
146  // No lower bound pruning possible
147  if (n_dis == 0)
148  return ES_NOFIX;
149 
150  // Only if the propagator is at fixpoint here, continue with
151  // propagating the lower bound
153  return ES_NOFIX;
154 
155  // Do lower bound-based pruning
156  GECODE_ES_CHECK(prune_lower(home,dis,n_dis));
157 
158  return ES_NOFIX;
159  }
160 
161 }}}
162 
163 // STATISTICS: int-prop
void notice(Actor &a, ActorProperty p, bool duplicate=false)
Notice actor property.
Definition: core.hpp:3219
Post propagator for SetVar x
Definition: set.hh:767
Post propagator for SetVar SetOpType SetVar y
Definition: set.hh:767
ExecStatus ES_SUBSUMED(Propagator &p)
Definition: core.hpp:3563
@ AP_WEAKLY
Definition: core.hpp:568
static ExecStatus post(Home home, ViewArray< View > &x)
Post propagator for views x.
Definition: dom.hpp:45
Class for storing values of already assigned views.
Definition: val-set.hh:44
bool assigned(View x, int v)
Whether x is assigned to value v.
Definition: single.hpp:43
Equal to number of values propagator for integer views.
Definition: nvalues.hh:185
const Gecode::ModEvent ME_INT_NONE
Domain operation has not changed domain.
Definition: var-type.hpp:54
bool disjoint(I &i, J &j)
Check whether range iterators i and j are disjoint.
Number of values propagator for integer views base class.
Definition: nvalues.hh:132
Computation spaces.
Definition: core.hpp:1742
bool assigned(void) const
Test whether view is assigned.
Definition: var.hpp:111
virtual ExecStatus propagate(Space &home, const ModEventDelta &med)
Perform propagation.
Definition: int-eq.hpp:116
const Gecode::ModEvent ME_INT_VAL
Domain operation has resulted in a value (assigned variable)
Definition: var-type.hpp:56
static ExecStatus post(Home home, ViewArray< IntView > &x, VY y)
Post propagator for .
Definition: int-eq.hpp:48
Gecode toplevel namespace
Base-class for propagators.
Definition: core.hpp:1064
int size(void) const
Return size (number of values)
Definition: val-set.hpp:81
#define GECODE_ES_CHECK(es)
Check whether execution status es is failed or subsumed, and forward failure or subsumption.
Definition: macros.hpp:91
Home class for posting propagators
Definition: core.hpp:856
static ModEvent me(const ModEventDelta &med)
Return modification event for view type in med.
Definition: view.hpp:552
Handle to region.
Definition: region.hpp:55
Post propagator for SetVar SetOpType SetVar SetRelType r
Definition: set.hh:767
ModEventDelta modeventdelta(void) const
Return the modification event delta.
Definition: core.hpp:3520
static ExecStatus post(Home home, ViewArray< View > &x)
Post domain consistent propagator .
Definition: eq.hpp:270
virtual Propagator * copy(Space &home)
Copy propagator during cloning.
Definition: int-eq.hpp:102
EqInt(Home home, ValSet &vs, ViewArray< IntView > &x, VY y)
Constructor for posting.
Definition: int-eq.hpp:41
#define forceinline
Definition: config.hpp:185
void ignore(Actor &a, ActorProperty p, bool duplicate=false)
Ignore actor property.
Definition: core.hpp:4074
#define GECODE_ME_CHECK(me)
Check whether modification event me is failed, and forward failure.
Definition: macros.hpp:52
int n
Number of negative literals for node type.
Definition: bool-expr.cpp:234
int ModEventDelta
Modification event deltas.
Definition: core.hpp:89
@ ES_NOFIX
Propagation has not computed fixpoint.
Definition: core.hpp:475
Gecode::IntArgs i({1, 2, 3, 4})
virtual size_t dispose(Space &home)
Delete propagator and return its size.
Definition: int-eq.hpp:108
@ ES_OK
Execution is okay.
Definition: core.hpp:476
int p
Number of positive literals for node type.
Definition: bool-expr.cpp:232
void add(Space &home, int v)
Add value v to value set.
Definition: val-set.hpp:45
ExecStatus
Definition: core.hpp:472