opt-prop.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, 2009 00008 * 00009 * Last modified: 00010 * $Date: 2010-07-15 12:52:54 +0200 (Thu, 15 Jul 2010) $ by $Author: tack $ 00011 * $Revision: 11200 $ 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 <algorithm> 00039 00040 namespace Gecode { namespace Scheduling { namespace Unary { 00041 00042 template<class OptTask> 00043 forceinline 00044 OptProp<OptTask>::OptProp(Home home, TaskArray<OptTask>& t) 00045 : TaskProp<OptTask,Int::PC_INT_BND>(home,t) {} 00046 00047 template<class OptTask> 00048 forceinline 00049 OptProp<OptTask>::OptProp(Space& home, bool shared, OptProp<OptTask>& p) 00050 : TaskProp<OptTask,Int::PC_INT_BND>(home,shared,p) {} 00051 00052 template<class OptTask> 00053 forceinline ExecStatus 00054 OptProp<OptTask>::post(Home home, TaskArray<OptTask>& t) { 00055 int m=0, o=0; 00056 for (int i=t.size(); i--; ) { 00057 if (t[i].mandatory()) 00058 m++; 00059 else if (t[i].optional()) 00060 o++; 00061 } 00062 if (m == t.size()) { 00063 TaskArray<typename TaskTraits<OptTask>::ManTask> mt(home,m); 00064 for (int i=m; i--; ) 00065 mt[i].init(t[i]); 00066 return ManProp<typename TaskTraits<OptTask>::ManTask>::post(home,mt); 00067 } 00068 if (o+m > 1) 00069 (void) new (home) OptProp<OptTask>(home,t); 00070 return ES_OK; 00071 } 00072 00073 template<class OptTask> 00074 Actor* 00075 OptProp<OptTask>::copy(Space& home, bool share) { 00076 return new (home) OptProp<OptTask>(home,share,*this); 00077 } 00078 00079 template<class OptTask> 00080 ExecStatus 00081 OptProp<OptTask>::propagate(Space& home, const ModEventDelta& med) { 00082 // Did one of the Boolean views change? 00083 if (Int::BoolView::me(med) == Int::ME_BOOL_VAL) 00084 GECODE_ES_CHECK((purge<OptTask,Int::PC_INT_BND>(home,*this,t))); 00085 00086 GECODE_ES_CHECK(overload(home,*this,t)); 00087 00088 GECODE_ES_CHECK(detectable(home,*this,t)); 00089 GECODE_ES_CHECK(notfirstnotlast(home,*this,t)); 00090 00091 // Partition into mandatory and optional activities 00092 int n = t.size(); 00093 int i=0, j=n-1; 00094 while (true) { 00095 while ((i < n) && t[i].mandatory()) i++; 00096 while ((j >= 0) && !t[j].mandatory()) j--; 00097 if (i >= j) break; 00098 std::swap(t[i],t[j]); 00099 } 00100 00101 if (i > 1) { 00102 // Truncate array to only contain mandatory tasks 00103 t.size(i); 00104 GECODE_ES_CHECK(edgefinding(home,t)); 00105 // Restore to also include optional tasks 00106 t.size(n); 00107 } 00108 00109 GECODE_ES_CHECK(subsumed(home,*this,t)); 00110 00111 return ES_NOFIX; 00112 } 00113 00114 }}} 00115 00116 // STATISTICS: scheduling-prop