unshare.cpp
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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: 2010-06-04 16:13:00 +0200 (Fri, 04 Jun 2010) $ by $Author: schulte $ 00011 * $Revision: 11028 $ 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 #include <gecode/int/rel.hh> 00039 #include <gecode/int/bool.hh> 00040 00046 namespace Gecode { 00047 00048 namespace Int { namespace Unshare { 00049 00051 template<class Var> 00052 class VarPtrLess { 00053 public: 00054 forceinline bool 00055 operator ()(const Var* a, const Var* b) { 00056 return a->before(*b); 00057 } 00058 }; 00059 00060 00062 forceinline ExecStatus 00063 link(Home home, IntVar** x, int n, IntConLevel icl) { 00064 if (n > 2) { 00065 ViewArray<IntView> y(home,n); 00066 y[0]=*x[0]; 00067 for (int i=1; i<n; i++) 00068 y[i]=*x[i]=IntVar(home,x[0]->min(),x[0]->max()); 00069 if ((icl == ICL_DOM) || (icl == ICL_DEF)) { 00070 GECODE_ES_CHECK(Rel::NaryEqDom<IntView>::post(home,y)); 00071 } else { 00072 GECODE_ES_CHECK(Rel::NaryEqBnd<IntView>::post(home,y)); 00073 } 00074 } else if (n == 2) { 00075 *x[1]=IntVar(home,x[0]->min(),x[0]->max()); 00076 if ((icl == ICL_DOM) || (icl == ICL_DEF)) { 00077 GECODE_ES_CHECK((Rel::EqDom<IntView,IntView>::post 00078 (home,*x[0],*x[1]))); 00079 } else { 00080 GECODE_ES_CHECK((Rel::EqBnd<IntView,IntView>::post 00081 (home,*x[0],*x[1]))); 00082 } 00083 } 00084 return ES_OK; 00085 } 00086 00088 forceinline ExecStatus 00089 link(Home home, BoolVar** x, int n, IntConLevel) { 00090 if (n > 2) { 00091 ViewArray<BoolView> y(home,n); 00092 y[0]=*x[0]; 00093 for (int i=1; i<n; i++) 00094 y[i]=*x[i]=BoolVar(home,0,1); 00095 GECODE_ES_CHECK(Bool::NaryEq<BoolView>::post(home,y)); 00096 } else if (n == 2) { 00097 *x[1] = BoolVar(home,0,1); 00098 GECODE_ES_CHECK((Bool::Eq<BoolView,BoolView>::post(home,*x[0],*x[1]))); 00099 } 00100 return ES_OK; 00101 } 00102 00104 template<class Var> 00105 forceinline ExecStatus 00106 unshare(Home home, VarArgArray<Var>& x, IntConLevel icl) { 00107 int n=x.size(); 00108 if (n < 2) 00109 return ES_OK; 00110 00111 Region r(home); 00112 Var** y = r.alloc<Var*>(n); 00113 for (int i=n; i--; ) 00114 y[i]=&x[i]; 00115 00116 VarPtrLess<Var> vpl; 00117 Support::quicksort<Var*,VarPtrLess<Var> >(y,n,vpl); 00118 00119 // Replace all shared variables with new and equal variables 00120 for (int i=0; i<n;) { 00121 int j=i++; 00122 while ((i<n) && y[j]->same(*y[i])) 00123 i++; 00124 if (!y[j]->assigned()) 00125 link(home,&y[j],i-j,icl); 00126 } 00127 return ES_OK; 00128 } 00129 00130 }} 00131 00132 void 00133 unshare(Home home, IntVarArgs& x, IntConLevel icl) { 00134 if (home.failed()) return; 00135 GECODE_ES_FAIL(Int::Unshare::unshare<IntVar>(home,x,icl)); 00136 } 00137 00138 void 00139 unshare(Home home, BoolVarArgs& x, IntConLevel) { 00140 if (home.failed()) return; 00141 GECODE_ES_FAIL(Int::Unshare::unshare<BoolVar>(home,x,ICL_DEF)); 00142 } 00143 00144 } 00145 00146 // STATISTICS: int-post