dom.hpp
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00001 /* -*- mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- */ 00002 /* 00003 * Main authors: 00004 * Christian Schulte <schulte@gecode.org> 00005 * 00006 * Copyright: 00007 * Christian Schulte, 2007 00008 * 00009 * Last modified: 00010 * $Date: 2010-03-03 17:32:21 +0100 (Wed, 03 Mar 2010) $ by $Author: schulte $ 00011 * $Revision: 10364 $ 00012 * 00013 * This file is part of Gecode, the generic constraint 00014 * development environment: 00015 * http://www.gecode.org 00016 * 00017 * Permission is hereby granted, free of charge, to any person obtaining 00018 * a copy of this software and associated documentation files (the 00019 * "Software"), to deal in the Software without restriction, including 00020 * without limitation the rights to use, copy, modify, merge, publish, 00021 * distribute, sublicense, and/or sell copies of the Software, and to 00022 * permit persons to whom the Software is furnished to do so, subject to 00023 * the following conditions: 00024 * 00025 * The above copyright notice and this permission notice shall be 00026 * included in all copies or substantial portions of the Software. 00027 * 00028 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 00029 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 00030 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 00031 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE 00032 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 00033 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 00034 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 00035 * 00036 */ 00037 00038 namespace Gecode { namespace Graph { namespace Circuit { 00039 00040 /* 00041 * The actual propagator 00042 * 00043 */ 00044 template<class View> 00045 forceinline 00046 Dom<View>::Dom(Home home, ViewArray<View>& x) 00047 : Base<View>(home,x) {} 00048 00049 template<class View> 00050 forceinline 00051 Dom<View>::Dom(Space& home, bool share, Dom<View>& p) 00052 : Base<View>(home,share,p) {} 00053 00054 template<class View> 00055 Actor* 00056 Dom<View>::copy(Space& home, bool share) { 00057 return new (home) Dom<View>(home,share,*this); 00058 } 00059 00060 template<class View> 00061 PropCost 00062 Dom<View>::cost(const Space&, const ModEventDelta& med) const { 00063 if (View::me(med) == Int::ME_INT_VAL) 00064 return PropCost::linear(PropCost::LO, x.size()); 00065 else 00066 return PropCost::quadratic(PropCost::HI, x.size()); 00067 } 00068 00069 template<class View> 00070 ExecStatus 00071 Dom<View>::propagate(Space& home, const ModEventDelta& med) { 00072 if (View::me(med) == Int::ME_INT_VAL) { 00073 GECODE_ES_CHECK((Int::Distinct::prop_val<View,true>(home,y))); 00074 ExecStatus escv = connected(home); 00075 if (escv != ES_FIX) 00076 return escv; 00077 if (y.size() < 2) 00078 return home.ES_SUBSUMED(*this); 00079 return home.ES_FIX_PARTIAL(*this,View::med(Int::ME_INT_DOM)); 00080 } 00081 00082 if (dc.available()) { 00083 GECODE_ES_CHECK(dc.sync(home)); 00084 } else { 00085 GECODE_ES_CHECK(dc.init(home,y.size(),&y[0])); 00086 } 00087 bool assigned; 00088 GECODE_ES_CHECK(dc.propagate(home,assigned)); 00089 00090 ExecStatus esc = connected(home); 00091 if (esc != ES_FIX) 00092 return esc; 00093 00094 // Elminiate assigned views from y, as they have been assigned 00095 // and propagated by domain consistent propagation. This is required 00096 // as we need to know how many assigned views actually exist. 00097 if (assigned) 00098 for (int i=y.size(); i--; ) 00099 if (y[i].assigned()) 00100 y.move_lst(i); 00101 00102 return path(home); 00103 } 00104 00105 template<class View> 00106 ExecStatus 00107 Dom<View>::post(Home home, ViewArray<View>& x) { 00108 int n = x.size(); 00109 if (n == 1) { 00110 GECODE_ME_CHECK(x[0].eq(home,0)); 00111 } else if (n == 2) { 00112 GECODE_ME_CHECK(x[0].eq(home,1)); 00113 GECODE_ME_CHECK(x[1].eq(home,0)); 00114 } else { 00115 for (int i=n; i--; ) { 00116 GECODE_ME_CHECK(x[i].gq(home,0)); 00117 GECODE_ME_CHECK(x[i].le(home,n)); 00118 GECODE_ME_CHECK(x[i].nq(home,i)); 00119 } 00120 (void) new (home) Dom<View>(home,x); 00121 } 00122 return ES_OK; 00123 } 00124 00125 }}} 00126 00127 // STATISTICS: graph-prop 00128