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int-gq.hpp
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33 
34 namespace Gecode { namespace Int { namespace Count {
35 
36  template<class VX, class VY>
38  GqInt<VX,VY>::GqInt(Home home, ViewArray<VX>& x, int n_s, VY y, int c)
39  : IntBase<VX,VY>(home,x,n_s,y,c) {}
40 
41  template<class VX, class VY>
44  // Eliminate decided views
45  int n_x = x.size();
46  for (int i=n_x; i--; )
47  switch (holds(x[i],y)) {
48  case RT_FALSE:
49  x[i] = x[--n_x]; break;
50  case RT_TRUE:
51  x[i] = x[--n_x]; c--; break;
52  case RT_MAYBE:
53  break;
54  default:
56  }
57  x.size(n_x);
58  // RHS too large
59  if (n_x < c)
60  return ES_FAILED;
61  // Whatever the x[i] take for values, the inequality is subsumed
62  if (c <= 0)
63  return ES_OK;
64  // All views must be equal
65  if (c == n_x)
66  return post_true(home,x,y);
67  (void) new (home) GqInt<VX,VY>(home,x,c+1,y,c);
68  return ES_OK;
69  }
70 
71  template<class VX, class VY>
74  : IntBase<VX,VY>(home,p) {}
75 
76  template<class VX, class VY>
77  Actor*
79  return new (home) GqInt<VX,VY>(home,*this);
80  }
81 
82  template<class VX, class VY>
85  // Eliminate decided views from subscribed views
86  int n_x = x.size();
87  for (int i=n_s; i--; )
88  switch (holds(x[i],y)) {
89  case RT_FALSE:
90  x[i].cancel(home,*this,PC_INT_DOM);
91  x[i]=x[--n_s]; x[n_s]=x[--n_x];
92  break;
93  case RT_TRUE:
94  x[i].cancel(home,*this,PC_INT_DOM);
95  x[i]=x[--n_s]; x[n_s]=x[--n_x]; c--;
96  break;
97  case RT_MAYBE:
98  break;
99  default:
100  GECODE_NEVER;
101  }
102  x.size(n_x);
103  if (n_x < c)
104  return ES_FAILED;
105  if (c <= 0)
106  return home.ES_SUBSUMED(*this);
107  // Eliminate decided views from unsubscribed views
108  for (int i=n_x; i-- > n_s; )
109  switch (holds(x[i],y)) {
110  case RT_FALSE: x[i]=x[--n_x]; break;
111  case RT_TRUE: x[i]=x[--n_x]; c--; break;
112  case RT_MAYBE: break;
113  default: GECODE_NEVER;
114  }
115  x.size(n_x);
116  if (n_x < c)
117  return ES_FAILED;
118  if (c <= 0)
119  return home.ES_SUBSUMED(*this);
120  if (c == n_x) {
121  // All views must be equal
122  GECODE_ES_CHECK(post_true(home,x,y));
123  return home.ES_SUBSUMED(*this);
124  }
125  // Now, there must be new subscriptions from x[n_s] up to x[c+1]
126  while (n_s <= c)
127  x[n_s++].subscribe(home,*this,PC_INT_DOM,false);
128  return ES_FIX;
129  }
130 
131 }}}
132 
133 // STATISTICS: int-prop
VY y
View to compare to.
Definition: count.hh:145
Relation may hold or not.
Definition: view.hpp:1703
ViewArray< VX > x
Views still to count.
Definition: count.hh:141
ExecStatus ES_SUBSUMED(Propagator &p)
Definition: core.hpp:3490
int n_s
Views from x[0] ... x[n_s-1] have subscriptions.
Definition: count.hh:143
RelTest holds(VX x, ConstIntView y)
Test whether x and y are equal.
Definition: rel.hpp:115
Baseclass for count propagators (integer)
Definition: count.hh:138
void subscribe(Space &home, Propagator &p, PropCond pc, bool schedule=true)
Subscribe propagator p with propagation condition pc to variable.
Definition: array.hpp:1323
#define forceinline
Definition: config.hpp:185
Propagation has computed fixpoint.
Definition: core.hpp:476
Computation spaces.
Definition: core.hpp:1701
Base-class for both propagators and branchers.
Definition: core.hpp:627
#define GECODE_ES_CHECK(es)
Check whether execution status es is failed or subsumed, and forward failure or subsumption.
Definition: macros.hpp:91
Gecode::FloatVal c(-8, 8)
int p
Number of positive literals for node type.
Definition: bool-expr.cpp:232
Gecode::IntArgs i({1, 2, 3, 4})
Execution has resulted in failure.
Definition: core.hpp:473
Relation does not hold.
Definition: view.hpp:1702
const Gecode::PropCond PC_INT_DOM
Propagate when domain changes.
Definition: var-type.hpp:100
int c
Number of views which are equal and have been eliminated.
Definition: count.hh:147
void cancel(Space &home, Propagator &p, PropCond pc)
Cancel subscription of propagator p with propagation condition pc to all views.
Definition: array.hpp:1331
Propagator for counting views (greater or equal integer to number of equal views) ...
Definition: count.hh:202
Post propagator for SetVar SetOpType SetVar y
Definition: set.hh:767
GqInt(Space &home, GqInt &p)
Constructor for cloning p.
Definition: int-gq.hpp:73
virtual Actor * copy(Space &home)
Create copy during cloning.
Definition: int-gq.hpp:78
virtual ExecStatus propagate(Space &home, const ModEventDelta &med)
Perform propagation.
Definition: int-gq.hpp:84
ExecStatus
Definition: core.hpp:471
Post propagator for SetVar x
Definition: set.hh:767
Execution is okay.
Definition: core.hpp:475
Gecode toplevel namespace
static ExecStatus post(Home home, ViewArray< VX > &x, VY y, int c)
Post propagator for .
Definition: int-gq.hpp:43
int ModEventDelta
Modification event deltas.
Definition: core.hpp:89
int size(void) const
Return size of array (number of elements)
Definition: array.hpp:1138
Home class for posting propagators
Definition: core.hpp:853
#define GECODE_NEVER
Assert that this command is never executed.
Definition: macros.hpp:56
Relation does hold.
Definition: view.hpp:1704
ExecStatus post_true(Home home, VX x, ConstIntView y)
Definition: rel.hpp:151