Generated on Mon Feb 8 2021 00:00:00 for Gecode by doxygen 1.8.20
dom.hpp
Go to the documentation of this file.
1 /* -*- mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- */
2 /*
3  * Main authors:
4  * Christian Schulte <schulte@gecode.org>
5  *
6  * Copyright:
7  * Christian Schulte, 2007
8  *
9  * This file is part of Gecode, the generic constraint
10  * development environment:
11  * http://www.gecode.org
12  *
13  * Permission is hereby granted, free of charge, to any person obtaining
14  * a copy of this software and associated documentation files (the
15  * "Software"), to deal in the Software without restriction, including
16  * without limitation the rights to use, copy, modify, merge, publish,
17  * distribute, sublicense, and/or sell copies of the Software, and to
18  * permit persons to whom the Software is furnished to do so, subject to
19  * the following conditions:
20  *
21  * The above copyright notice and this permission notice shall be
22  * included in all copies or substantial portions of the Software.
23  *
24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
28  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
29  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
30  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
31  *
32  */
33 
34 namespace Gecode { namespace Int { namespace Circuit {
35 
36  /*
37  * The actual propagator
38  *
39  */
40  template<class View, class Offset>
43  : Base<View,Offset>(home,x,o) {}
44 
45  template<class View, class Offset>
48  : Base<View,Offset>(home,p) {}
49 
50  template<class View, class Offset>
51  Actor*
53  return new (home) Dom<View,Offset>(home,*this);
54  }
55 
56  template<class View, class Offset>
57  PropCost
58  Dom<View,Offset>::cost(const Space&, const ModEventDelta& med) const {
59  if (View::me(med) == Int::ME_INT_VAL)
60  return PropCost::linear(PropCost::LO, x.size());
61  else
62  return PropCost::quadratic(PropCost::HI, x.size());
63  }
64 
65  template<class View, class Offset>
66  void
68  for (int i=0; i<y.size(); i++)
69  if (y[i].assigned()) {
70  View::schedule(home, *this, ME_INT_VAL);
71  return;
72  }
73  View::schedule(home, *this, ME_INT_DOM);
74  }
75 
76  template<class View, class Offset>
79  if (View::me(med) == Int::ME_INT_VAL) {
80  GECODE_ES_CHECK((Int::Distinct::prop_val<View,true>(home,y)));
81  ExecStatus escv = connected(home);
82  if (escv != ES_FIX)
83  return escv;
84  if (y.size() < 2)
85  return home.ES_SUBSUMED(*this);
86  return home.ES_FIX_PARTIAL(*this,View::med(Int::ME_INT_DOM));
87  }
88 
89  if (dc.available()) {
90  GECODE_ES_CHECK(dc.sync());
91  } else {
92  GECODE_ES_CHECK(dc.init(home,y));
93  }
94  bool assigned;
95  GECODE_ES_CHECK(dc.propagate(home,assigned));
96 
97  ExecStatus esc = connected(home);
98  if (esc != ES_FIX)
99  return esc;
100 
101  // Elminiate assigned views from y, as they have been assigned
102  // and propagated by domain consistent propagation. This is required
103  // as we need to know how many assigned views actually exist.
104  if (assigned)
105  for (int i=y.size(); i--; )
106  if (y[i].assigned())
107  y.move_lst(i);
108 
109  return path(home);
110  }
111 
112  template<class View, class Offset>
113  ExecStatus
115  int n = x.size();
116  if (n == 1) {
117  GECODE_ME_CHECK(o(x[0]).eq(home,0));
118  } else if (n == 2) {
119  GECODE_ME_CHECK(o(x[0]).eq(home,1));
120  GECODE_ME_CHECK(o(x[1]).eq(home,0));
121  } else {
122  for (int i=0; i<n; i++) {
123  GECODE_ME_CHECK(o(x[i]).gq(home,0));
124  GECODE_ME_CHECK(o(x[i]).le(home,n));
125  GECODE_ME_CHECK(o(x[i]).nq(home,i));
126  }
127  (void) new (home) Dom<View,Offset>(home,x,o);
128  }
129  return ES_OK;
130  }
131 
132 }}}
133 
134 // STATISTICS: int-prop
135 
Post propagator for SetVar x
Definition: set.hh:767
Post propagator for SetVar SetOpType SetVar y
Definition: set.hh:767
Converter with fixed offset.
Definition: view.hpp:650
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, ViewArray< View > &x, Offset &o)
Post propagator for circuit on x.
Definition: dom.hpp:114
@ LO
Cheap.
Definition: core.hpp:513
Computation spaces.
Definition: core.hpp:1742
static PropCost linear(PropCost::Mod m, unsigned int n)
Linear complexity for modifier pcm and size measure n.
Definition: core.hpp:4796
Base-class for both propagators and branchers.
Definition: core.hpp:628
static PropCost quadratic(PropCost::Mod m, unsigned int n)
Quadratic complexity for modifier m and size measure n.
Definition: core.hpp:4787
const Gecode::ModEvent ME_INT_VAL
Domain operation has resulted in a value (assigned variable)
Definition: var-type.hpp:56
Dom(Space &home, Dom &p)
Constructor for cloning p.
Gecode toplevel namespace
Base-class for circuit propagator.
Definition: circuit.hh:55
#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
virtual PropCost cost(const Space &home, const ModEventDelta &med) const
Cost function.
Definition: dom.hpp:58
"Domain consistent" circuit propagator
Definition: circuit.hh:121
Propagation cost.
Definition: core.hpp:486
@ ES_FIX
Propagation has computed fixpoint.
Definition: core.hpp:477
void path(Home home, int offset, const IntVarArgs &x, IntVar s, IntVar e, IntPropLevel ipl)
Post propagator such that x forms a Hamiltonian path.
Definition: circuit.cpp:124
#define forceinline
Definition: config.hpp:192
virtual ExecStatus propagate(Space &home, const ModEventDelta &med)
Perform propagation.
Definition: dom.hpp:78
virtual Actor * copy(Space &home)
Copy propagator during cloning.
Definition: dom.hpp:52
#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
View arrays.
Definition: array.hpp:253
int n
Number of negative literals for node type.
Definition: bool-expr.cpp:234
ExecStatus ES_FIX_PARTIAL(Propagator &p, const ModEventDelta &med)
Propagator p has computed partial fixpoint
Definition: core.hpp:3569
int ModEventDelta
Modification event deltas.
Definition: core.hpp:89
Gecode::IntArgs i({1, 2, 3, 4})
const Gecode::ModEvent ME_INT_DOM
Domain operation has changed the domain.
Definition: var-type.hpp:72
@ ES_OK
Execution is okay.
Definition: core.hpp:476
int p
Number of positive literals for node type.
Definition: bool-expr.cpp:232
virtual void reschedule(Space &home)
Schedule function.
Definition: dom.hpp:67
ExecStatus
Definition: core.hpp:472