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int-lq.hpp
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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  GECODE_ME_CHECK(y.gq(home,1));
57 
58  if (x.size() == 1)
59  return ES_OK;
60 
61  if (y.max() == 1) {
62  assert(y.assigned());
63  return Rel::NaryEqDom<IntView>::post(home,x);
64  }
65 
66  if (y.min() >= x.size())
67  return ES_OK;
68 
69  // Eliminate assigned views and store them into the value set
70  ValSet vs;
71  int n = x.size();
72  for (int i=n; i--; )
73  if (x[i].assigned()) {
74  vs.add(home, x[i].val());
75  x[i] = x[--n];
76  }
77 
78  GECODE_ME_CHECK(y.gq(home,vs.size()));
79 
80  if (n == 0) {
81  assert(y.min() >= vs.size());
82  return ES_OK;
83  }
84 
85  x.size(n);
86 
87  (void) new (home) LqInt<VY>(home, vs, x, y);
88  return ES_OK;
89  }
90 
91  template<class VY>
94  : IntBase<VY>(home, p) {}
95 
96  template<class VY>
97  Propagator*
99  return new (home) LqInt<VY>(home, *this);
100  }
101 
102  template<class VY>
103  forceinline size_t
105  home.ignore(*this, AP_WEAKLY);
106  (void) IntBase<VY>::dispose(home);
107  return sizeof(*this);
108  }
109 
110  template<class VY>
111  ExecStatus
113  // Add assigned views to value set
114  if (IntView::me(med) == ME_INT_VAL)
115  add(home);
116 
117  GECODE_ME_CHECK(y.gq(home, vs.size()));
118 
119  if (x.size() == 0)
120  return home.ES_SUBSUMED(*this);
121 
122  // All values must be in the value set
123  if (y.max() == vs.size())
124  return all_in_valset(home);
125 
126  if (x.size() + vs.size() <= y.min())
127  return home.ES_SUBSUMED(*this);
128 
129  // Compute positions of disjoint views
130  Region r;
131  int* dis; int n_dis;
132  disjoint(home,r,dis,n_dis);
133 
134  // Some views might have been eliminated as they are subsumed
135  if (x.size() == 0)
136  return home.ES_SUBSUMED(*this);
137 
138  // No lower bound pruning possible
139  if (n_dis == 0)
140  return ES_NOFIX;
141 
142  // Do lower bound-based pruning
143  GECODE_ES_CHECK(prune_lower(home,dis,n_dis));
144 
145  return ES_NOFIX;
146  }
147 
148 }}}
149 
150 // STATISTICS: int-prop
ExecStatus prune_lower(Space &home, int *dis, int n_dis)
Definition: int-base.hpp:130
virtual ExecStatus propagate(Space &home, const ModEventDelta &med)
Perform propagation.
Definition: int-lq.hpp:112
void add(Space &home)
Add values of assigned views to value set.
Definition: int-base.hpp:68
ExecStatus ES_SUBSUMED(Propagator &p)
Definition: core.hpp:3482
virtual size_t dispose(Space &home)
Delete propagator and return its size.
Definition: int-lq.hpp:104
LqInt(Home home, ValSet &vs, ViewArray< IntView > &x, VY y)
Constructor for posting.
Definition: int-lq.hpp:41
Base-class for propagators.
Definition: core.hpp:1023
Handle to region.
Definition: region.hpp:53
#define forceinline
Definition: config.hpp:185
Computation spaces.
Definition: core.hpp:1701
#define GECODE_ES_CHECK(es)
Check whether execution status es is failed or subsumed, and forward failure or subsumption.
Definition: macros.hpp:91
ExecStatus all_in_valset(Space &home)
Propagate that all views must take values from value set.
Definition: int-base.hpp:120
int p
Number of positive literals for node type.
Definition: bool-expr.cpp:232
Gecode::IntArgs i(4, 1, 2, 3, 4)
int n
Number of negative literals for node type.
Definition: bool-expr.cpp:234
int size(void) const
Return size (number of values)
Definition: val-set.hpp:81
const Gecode::ModEvent ME_INT_VAL
Domain operation has resulted in a value (assigned variable)
Definition: var-type.hpp:56
ModEventDelta med
A set of modification events (used during propagation)
Definition: core.hpp:1034
ValSet vs
Value set storing the values of already assigned views.
Definition: nvalues.hh:138
#define GECODE_ME_CHECK(me)
Check whether modification event me is failed, and forward failure.
Definition: macros.hpp:52
void notice(Actor &a, ActorProperty p, bool duplicate=false)
Notice actor property.
Definition: core.hpp:3176
Post propagator for SetVar SetOpType SetVar SetRelType r
Definition: set.hh:765
Less or equal to number of values propagator for integer views.
Definition: nvalues.hh:219
void disjoint(Space &home, Region &r, int *&dis, int &n_dis)
Definition: int-base.hpp:80
Post propagator for SetVar SetOpType SetVar y
Definition: set.hh:765
void ignore(Actor &a, ActorProperty p, bool duplicate=false)
Ignore actor property.
Definition: core.hpp:3993
ExecStatus
Definition: core.hpp:471
bool assigned(View x, int v)
Whether x is assigned to value v.
Definition: single.hpp:43
static ModEvent me(const ModEventDelta &med)
Return modification event for view type in med.
Definition: view.hpp:540
Post propagator for SetVar x
Definition: set.hh:765
Execution is okay.
Definition: core.hpp:475
Propagation has not computed fixpoint.
Definition: core.hpp:474
void unique(void)
Remove all duplicate views from array (changes element order)
Definition: array.hpp:1489
Class for storing values of already assigned views.
Definition: val-set.hh:44
Gecode toplevel namespace
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-lq.hpp:98
Number of values propagator for integer views base class.
Definition: nvalues.hh:132
int ModEventDelta
Modification event deltas.
Definition: core.hpp:89
int size(void) const
Return size of array (number of elements)
Definition: array.hpp:1199
Home class for posting propagators
Definition: core.hpp:853
void add(Space &home, int v)
Add value v to value set.
Definition: val-set.hpp:45
static ExecStatus post(Home home, ViewArray< IntView > &x, VY y)
Post propagator for .
Definition: int-lq.hpp:48