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eqite.cpp
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4  * Christian Schulte <schulte@gecode.org>
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7  * Christian Schulte, 2015
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33 
34 #include <gecode/int/distinct.hh>
35 
36 #include <algorithm>
37 
38 namespace Gecode { namespace Int { namespace Distinct {
39 
40  PropCost
41  EqIte::cost(const Space&, const ModEventDelta&) const {
43  }
44 
45  Actor*
46  EqIte::copy(Space& home) {
47  return new (home) EqIte(home,*this);
48  }
49 
52  switch (rtest_eq_dom(x0,c0)) {
53  case RT_TRUE:
54  GECODE_ME_CHECK(x1.eq(home,c1));
55  return home.ES_SUBSUMED(*this);
56  case RT_FALSE:
58  ::post(home(*this),x0,x1)));
60  case RT_MAYBE:
61  break;
62  default: GECODE_NEVER;
63  }
64 
65  GECODE_ME_CHECK(x1.lq(home,std::max(x0.max(),c1)));
66  GECODE_ME_CHECK(x1.gq(home,std::min(x0.min(),c1)));
67 
68  RelTest eq_then = rtest_eq_dom(x1,c1);
69  RelTest eq_else = rtest_eq_dom(x1,x0);
70 
71  if ((eq_then == RT_FALSE) && (eq_else == RT_FALSE))
72  return ES_FAILED;
73 
74  if (eq_then == RT_FALSE) {
75  // x1 and c1 are not equal
76  GECODE_ME_CHECK(x0.nq(home,c0));
77  if (eq_else == RT_TRUE)
78  return home.ES_SUBSUMED(*this);
79  else
80  GECODE_REWRITE(*this,
81  (Rel::EqDom<IntView,IntView>::post(home(*this),x0,x1)));
82  }
83 
84  if (eq_else == RT_FALSE) {
85  // x0 and x1 are not equal
86  GECODE_ME_CHECK(x0.eq(home,c0));
87  GECODE_ME_CHECK(x1.eq(home,c1));
88  return home.ES_SUBSUMED(*this);
89  }
90 
91 
92  assert((eq_then != RT_TRUE) || (eq_else != RT_TRUE));
93 
97  Iter::Ranges::Singleton > u(r0,r1);
98 
99  GECODE_ME_CHECK(x1.inter_r(home,u,true));
100 
101  return ES_FIX;
102  }
103 
104 }}}
105 
106 // STATISTICS: int-prop
int c1
Definition: distinct.hh:354
ExecStatus ES_SUBSUMED(Propagator &p)
Definition: core.hpp:3563
int min(void) const
Return minimum of domain.
Definition: int.hpp:58
static PropCost binary(PropCost::Mod m)
Two variables for modifier pcm.
Definition: core.hpp:4809
EqIte(Space &home, EqIte &p)
Constructor for cloning p.
Definition: eqite.hpp:43
virtual PropCost cost(const Space &home, const ModEventDelta &med) const
Cost function (defined as high ternary)
Definition: eqite.cpp:41
const FloatNum min
Smallest allowed float value.
Definition: float.hh:846
Computation spaces.
Definition: core.hpp:1742
Base-class for both propagators and branchers.
Definition: core.hpp:628
static ExecStatus post(Home home, IntView x0, IntView x1, int c0, int c1)
Post if-then-else propagator.
Definition: eqite.hpp:49
@ RT_TRUE
Relation does hold.
Definition: view.hpp:1737
virtual ExecStatus propagate(Space &home, const ModEventDelta &med)
Perform propagation.
Definition: eqite.cpp:51
Gecode toplevel namespace
int max(void) const
Return maximum of domain.
Definition: int.hpp:62
@ RT_MAYBE
Relation may hold or not.
Definition: view.hpp:1736
union Gecode::@602::NNF::@65 u
Union depending on nodetype t.
ModEvent inter_r(Space &home, I &i, bool depends=true)
Intersect domain with ranges described by i.
Definition: int.hpp:186
Binary domain consistent equality propagator.
Definition: rel.hh:68
RelTest rtest_eq_dom(VX x, VY y)
Test whether views x and y are equal (use full domain information)
Definition: rel-test.hpp:65
@ RT_FALSE
Relation does not hold.
Definition: view.hpp:1735
IntView x1
Definition: pattern.hpp:87
ModEvent nq(Space &home, int n)
Restrict domain values to be different from n.
Definition: int.hpp:157
int c0
The integer constant.
Definition: distinct.hh:354
#define GECODE_NEVER
Assert that this command is never executed.
Definition: macros.hpp:56
Range iterator for computing union (binary)
@ ES_FIX
Propagation has computed fixpoint.
Definition: core.hpp:477
Range iterator for integer variable views
Definition: int.hpp:246
RelTest
Result of testing relation.
Definition: view.hpp:1734
Range iterator for singleton range.
#define GECODE_ME_CHECK(me)
Check whether modification event me is failed, and forward failure.
Definition: macros.hpp:52
@ HI
Expensive.
Definition: core.hpp:514
ModEvent lq(Space &home, int n)
Restrict domain values to be less or equal than n.
Definition: int.hpp:121
virtual Actor * copy(Space &home)
Copy propagator during cloning.
Definition: eqite.cpp:46
ModEvent gq(Space &home, int n)
Restrict domain values to be greater or equal than n.
Definition: int.hpp:139
@ ES_FAILED
Execution has resulted in failure.
Definition: core.hpp:474
int ModEventDelta
Modification event deltas.
Definition: core.hpp:89
#define GECODE_REWRITE(prop, post)
Rewrite propagator by executing post function.
Definition: macros.hpp:116
IntView x0
Two views.
Definition: pattern.hpp:87
const FloatNum max
Largest allowed float value.
Definition: float.hh:844
ModEvent eq(Space &home, int n)
Restrict domain values to be equal to n.
Definition: int.hpp:166
ExecStatus
Definition: core.hpp:472