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eq.hpp
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33 
34 namespace Gecode { namespace Int { namespace Bool {
35 
36  template<class BVA, class BVB>
38  Eq<BVA,BVB>::Eq(Home home, BVA b0, BVB b1)
39  : BoolBinary<BVA,BVB>(home,b0,b1) {}
40 
41  template<class BVA, class BVB>
44  : BoolBinary<BVA,BVB>(home,p) {}
45 
46  template<class BVA, class BVB>
49  BVA b0, BVB b1)
50  : BoolBinary<BVA,BVB>(home,p,b0,b1) {}
51 
52  template<class BVA, class BVB>
53  Actor*
55  return new (home) Eq<BVA,BVB>(home,*this);
56  }
57 
58  template<class BVA, class BVB>
59  inline ExecStatus
60  Eq<BVA,BVB>::post(Home home, BVA b0, BVB b1) {
61  switch (bool_test(b0,b1)) {
62  case BT_SAME: return ES_OK;
63  case BT_COMP: return ES_FAILED;
64  case BT_NONE:
65  if (b0.zero()) {
66  GECODE_ME_CHECK(b1.zero(home));
67  } else if (b0.one()) {
68  GECODE_ME_CHECK(b1.one(home));
69  } else if (b1.zero()) {
70  GECODE_ME_CHECK(b0.zero(home));
71  } else if (b1.one()) {
72  GECODE_ME_CHECK(b0.one(home));
73  } else {
74  (void) new (home) Eq<BVA,BVB>(home,b0,b1);
75  }
76  break;
77  default: GECODE_NEVER;
78  }
79  return ES_OK;
80  }
81 
82  template<class BVA, class BVB>
85 #define GECODE_INT_STATUS(S0,S1) \
86  ((BVA::S0<<(1*BVA::BITS))|(BVB::S1<<(0*BVB::BITS)))
87  switch ((x0.status() << (1*BVA::BITS)) | (x1.status() << (0*BVB::BITS))) {
88  case GECODE_INT_STATUS(NONE,NONE):
90  case GECODE_INT_STATUS(NONE,ZERO):
91  GECODE_ME_CHECK(x0.zero_none(home)); break;
92  case GECODE_INT_STATUS(NONE,ONE):
93  GECODE_ME_CHECK(x0.one_none(home)); break;
94  case GECODE_INT_STATUS(ZERO,NONE):
95  GECODE_ME_CHECK(x1.zero_none(home)); break;
96  case GECODE_INT_STATUS(ZERO,ZERO):
97  break;
98  case GECODE_INT_STATUS(ZERO,ONE):
99  return ES_FAILED;
100  case GECODE_INT_STATUS(ONE,NONE):
101  GECODE_ME_CHECK(x1.one_none(home)); break;
102  case GECODE_INT_STATUS(ONE,ZERO):
103  return ES_FAILED;
104  case GECODE_INT_STATUS(ONE,ONE):
105  break;
106  default:
107  GECODE_NEVER;
108  }
109  return home.ES_SUBSUMED(*this);
110 #undef GECODE_INT_STATUS
111  }
112 
113  template<class BV>
116  : NaryPropagator<BV,PC_BOOL_VAL>(home,x) {}
117 
118  template<class BV>
121  : NaryPropagator<BV,PC_BOOL_VAL>(home,p) {}
122 
123  template<class BV>
124  Actor*
126  return new (home) NaryEq<BV>(home,*this);
127  }
128 
129  template<class BV>
130  inline ExecStatus
132  x.unique();
133  int n = x.size();
134  if (n < 2)
135  return ES_OK;
136  if (n == 2)
137  return Eq<BV,BV>::post(home,x[0],x[1]);
138  for (int i=n; i--; )
139  if (x[i].assigned()) {
140  if (x[i].one()) {
141  for (int j=0; j<i; j++)
142  GECODE_ME_CHECK(x[j].one(home));
143  for (int j=i+1; j<n; j++)
144  GECODE_ME_CHECK(x[j].one_none(home));
145  } else {
146  for (int j=0; j<i; j++)
147  GECODE_ME_CHECK(x[j].zero(home));
148  for (int j=i+1; j<n; j++)
149  GECODE_ME_CHECK(x[j].zero_none(home));
150  }
151  return ES_OK;
152  }
153  (void) new (home) NaryEq<BV>(home,x);
154  return ES_OK;
155  }
156 
157  template<class BV>
158  PropCost
159  NaryEq<BV>::cost(const Space&, const ModEventDelta&) const {
161  }
162 
163  template<class BV>
164  ExecStatus
166  int n=x.size();
167  int i=0;
168  while (true) {
169  if (x[i].assigned()) {
170  if (x[i].one()) {
171  for (int j=0; j<i; j++)
172  GECODE_ME_CHECK(x[j].one_none(home));
173  for (int j=i+1; j<n; j++)
174  GECODE_ME_CHECK(x[j].one(home));
175  } else {
176  for (int j=0; j<i; j++)
177  GECODE_ME_CHECK(x[j].zero_none(home));
178  for (int j=i+1; j<n; j++)
179  GECODE_ME_CHECK(x[j].zero(home));
180  }
181  return home.ES_SUBSUMED(*this);
182  }
183  i++;
184  }
185  GECODE_NEVER;
186  return ES_FIX;
187  }
188 
189 }}}
190 
191 // STATISTICS: int-prop
192 
Post propagator for SetVar x
Definition: set.hh:767
const Gecode::PropCond PC_BOOL_VAL
Propagate when a view becomes assigned (single value)
Definition: var-type.hpp:126
static ExecStatus post(Home home, ViewArray< BV > &x)
Post propagator .
Definition: eq.hpp:131
ExecStatus ES_SUBSUMED(Propagator &p)
Definition: core.hpp:3563
bool assigned(View x, int v)
Whether x is assigned to value v.
Definition: single.hpp:43
static ExecStatus post(Home home, BVA x0, BVB x1)
Post propagator .
Definition: eq.hpp:60
virtual Actor * copy(Space &home)
Copy propagator during cloning.
Definition: eq.hpp:125
@ LO
Cheap.
Definition: core.hpp:513
Computation spaces.
Definition: core.hpp:1742
Base-class for both propagators and branchers.
Definition: core.hpp:628
#define GECODE_INT_STATUS(S0, S1)
virtual PropCost cost(const Space &home, const ModEventDelta &med) const
Cost function (defined as low unary)
Definition: eq.hpp:159
virtual ExecStatus propagate(Space &home, const ModEventDelta &med)
Perform propagation.
Definition: eq.hpp:84
Gecode toplevel namespace
Base-class for propagators.
Definition: core.hpp:1064
Basic b1(3)
@ BT_NONE
No sharing.
Definition: view.hpp:1785
Home class for posting propagators
Definition: core.hpp:856
static PropCost unary(PropCost::Mod m)
Single variable for modifier pcm.
Definition: core.hpp:4813
n-ary propagator
Definition: pattern.hpp:142
@ BT_SAME
Same variable.
Definition: view.hpp:1786
Boolean equality propagator.
Definition: bool.hh:105
bool one(const Gecode::FloatValArgs &a)
Check whether has only one coefficients.
Definition: linear.cpp:46
n-ary Boolean equality propagator
Definition: bool.hh:133
virtual ExecStatus propagate(Space &home, const ModEventDelta &med)
Perform propagation.
Definition: eq.hpp:165
#define GECODE_NEVER
Assert that this command is never executed.
Definition: macros.hpp:56
Base-class for binary Boolean propagators.
Definition: bool.hh:55
Propagation cost.
Definition: core.hpp:486
BoolTest bool_test(const BoolView &b0, const BoolView &b1)
Definition: bool-test.hpp:41
NaryEq(Home home, ViewArray< BV > &x)
Constructor for posting.
Definition: eq.hpp:115
@ ES_FIX
Propagation has computed fixpoint.
Definition: core.hpp:477
#define forceinline
Definition: config.hpp:185
#define GECODE_ME_CHECK(me)
Check whether modification event me is failed, and forward failure.
Definition: macros.hpp:52
virtual Actor * copy(Space &home)
Copy propagator during cloning.
Definition: eq.hpp:54
int n
Number of negative literals for node type.
Definition: bool-expr.cpp:234
@ ES_FAILED
Execution has resulted in failure.
Definition: core.hpp:474
int ModEventDelta
Modification event deltas.
Definition: core.hpp:89
Gecode::IntArgs i({1, 2, 3, 4})
@ ES_OK
Execution is okay.
Definition: core.hpp:476
int p
Number of positive literals for node type.
Definition: bool-expr.cpp:232
Eq(Home home, BVA b0, BVB b1)
Constructor for posting.
Definition: eq.hpp:38
@ BT_COMP
Same variable but complement.
Definition: view.hpp:1787
ExecStatus
Definition: core.hpp:472