1 /* -*- mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- */ 2 /* 3 * Main authors: 4 * Christian Schulte <schulte@gecode.org> 5 * Guido Tack <tack@gecode.org> 6 * 7 * Copyright: 8 * Christian Schulte, 2004 9 * Guido Tack, 2006 10 * 11 * This file is part of Gecode, the generic constraint 12 * development environment: 13 * http://www.gecode.org 14 * 15 * Permission is hereby granted, free of charge, to any person obtaining 16 * a copy of this software and associated documentation files (the 17 * "Software"), to deal in the Software without restriction, including 18 * without limitation the rights to use, copy, modify, merge, publish, 19 * distribute, sublicense, and/or sell copies of the Software, and to 20 * permit persons to whom the Software is furnished to do so, subject to 21 * the following conditions: 22 * 23 * The above copyright notice and this permission notice shall be 24 * included in all copies or substantial portions of the Software. 25 * 26 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 27 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 28 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 29 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE 30 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 31 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 32 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 33 * 34 */ 35 36 #include <algorithm> 37 38 namespace Gecode { namespace Int { namespace Arithmetic { 39 40 template<class View, template<class View0,class View1> class Eq> 41 ExecStatus prop_abs_bnd(Space & home,Propagator & p,View x0,View x1)42 prop_abs_bnd(Space& home, Propagator& p, View x0, View x1) { 43 if (x0.assigned()) { 44 GECODE_ME_CHECK(x1.eq(home,(x0.val() < 0) ? -x0.val() : x0.val())); 45 return home.ES_SUBSUMED(p); 46 } 47 48 if (x1.assigned()) { 49 if (x0.min() >= 0) { 50 GECODE_ME_CHECK(x0.eq(home,x1.val())); 51 return home.ES_SUBSUMED(p); 52 } else if (x0.max() <= 0) { 53 GECODE_ME_CHECK(x0.eq(home,-x1.val())); 54 return home.ES_SUBSUMED(p); 55 } else if (x1.val() == 0) { 56 GECODE_ME_CHECK(x0.eq(home,0)); 57 return home.ES_SUBSUMED(p); 58 } else { 59 int mp[2] = {-x1.val(),x1.val()}; 60 Iter::Values::Array i(mp,2); 61 GECODE_ME_CHECK(x0.inter_v(home,i,false)); 62 return home.ES_SUBSUMED(p); 63 } 64 } 65 66 if (x0.min() >= 0) 67 GECODE_REWRITE(p,(Eq<View,View>::post(home(p),x0,x1))); 68 69 if (x0.max() <= 0) 70 GECODE_REWRITE(p,(Eq<MinusView,View>::post(home(p),MinusView(x0),x1))); 71 72 73 GECODE_ME_CHECK(x1.lq(home,std::max(x0.max(),-x0.min()))); 74 GECODE_ME_CHECK(x0.gq(home,-x1.max())); 75 GECODE_ME_CHECK(x0.lq(home,x1.max())); 76 if (x1.min() > 0) { 77 if (-x1.min() < x0.min()) { 78 GECODE_ME_CHECK(x0.gq(home,x1.min())); 79 } else if (x0.max() < x1.min()) { 80 GECODE_ME_CHECK(x0.lq(home,-x1.min())); 81 } 82 } 83 return ES_NOFIX; 84 } 85 86 template<class View> 87 forceinline AbsBnd(Home home,View x0,View x1)88 AbsBnd<View>::AbsBnd(Home home, View x0, View x1) 89 : BinaryPropagator<View,PC_INT_BND>(home,x0,x1) {} 90 91 template<class View> 92 ExecStatus post(Home home,View x0,View x1)93 AbsBnd<View>::post(Home home, View x0, View x1) { 94 if (x0.min() >= 0) { 95 return Rel::EqBnd<View,View>::post(home,x0,x1); 96 } else if (x0.max() <= 0) { 97 return Rel::EqBnd<MinusView,View>::post(home,MinusView(x0),x1); 98 } else { 99 assert(!x0.assigned()); 100 GECODE_ME_CHECK(x1.gq(home,0)); 101 if (x1.assigned()) { 102 int mp[2] = {-x1.val(),x1.val()}; 103 Iter::Values::Array i(mp,2); 104 GECODE_ME_CHECK(x0.inter_v(home,i,false)); 105 } else if (x0 != x1) { 106 GECODE_ME_CHECK(x1.lq(home,std::max(-x0.min(),x0.max()))); 107 (void) new (home) AbsBnd<View>(home,x0,x1); 108 } 109 } 110 return ES_OK; 111 } 112 113 template<class View> 114 forceinline AbsBnd(Space & home,AbsBnd<View> & p)115 AbsBnd<View>::AbsBnd(Space& home, AbsBnd<View>& p) 116 : BinaryPropagator<View,PC_INT_BND>(home,p) {} 117 118 template<class View> 119 Actor* copy(Space & home)120 AbsBnd<View>::copy(Space& home) { 121 return new (home) AbsBnd<View>(home,*this); 122 } 123 124 template<class View> 125 PropCost cost(const Space &,const ModEventDelta & med) const126 AbsBnd<View>::cost(const Space&, const ModEventDelta& med) const { 127 if (View::me(med) == ME_INT_VAL) 128 return PropCost::unary(PropCost::LO); 129 else 130 return PropCost::binary(PropCost::LO); 131 } 132 133 template<class View> 134 ExecStatus propagate(Space & home,const ModEventDelta &)135 AbsBnd<View>::propagate(Space& home, const ModEventDelta&) { 136 return prop_abs_bnd<View,Rel::EqBnd>(home, *this, x0, x1); 137 } 138 139 140 141 template<class View> 142 forceinline AbsDom(Home home,View x0,View x1)143 AbsDom<View>::AbsDom(Home home, View x0, View x1) 144 : BinaryPropagator<View,PC_INT_DOM>(home,x0,x1) {} 145 146 template<class View> 147 ExecStatus post(Home home,View x0,View x1)148 AbsDom<View>::post(Home home, View x0, View x1) { 149 if (x0.min() >= 0) { 150 return Rel::EqDom<View,View>::post(home,x0,x1); 151 } else if (x0.max() <= 0) { 152 return Rel::EqDom<MinusView,View>::post(home,MinusView(x0),x1); 153 } else { 154 assert(!x0.assigned()); 155 GECODE_ME_CHECK(x1.gq(home,0)); 156 if (x1.assigned()) { 157 int mp[2] = {-x1.val(),x1.val()}; 158 Iter::Values::Array i(mp,2); 159 GECODE_ME_CHECK(x0.inter_v(home,i,false)); 160 } else if (x0 != x1) { 161 GECODE_ME_CHECK(x1.lq(home,std::max(-x0.min(),x0.max()))); 162 (void) new (home) AbsDom<View>(home,x0,x1); 163 } 164 } 165 return ES_OK; 166 } 167 168 template<class View> 169 forceinline AbsDom(Space & home,AbsDom<View> & p)170 AbsDom<View>::AbsDom(Space& home, AbsDom<View>& p) 171 : BinaryPropagator<View,PC_INT_DOM>(home,p) {} 172 173 template<class View> 174 Actor* copy(Space & home)175 AbsDom<View>::copy(Space& home) { 176 return new (home) AbsDom<View>(home,*this); 177 } 178 179 template<class View> 180 PropCost cost(const Space &,const ModEventDelta & med) const181 AbsDom<View>::cost(const Space&, const ModEventDelta& med) const { 182 if (View::me(med) == ME_INT_VAL) 183 return PropCost::unary(PropCost::LO); 184 else 185 return PropCost::binary((View::me(med) == ME_INT_DOM) ? 186 PropCost::HI : PropCost::LO); 187 } 188 189 template<class View> 190 ExecStatus propagate(Space & home,const ModEventDelta & med)191 AbsDom<View>::propagate(Space& home, const ModEventDelta& med) { 192 if (View::me(med) != ME_INT_DOM) { 193 GECODE_ES_CHECK((prop_abs_bnd<View,Rel::EqDom>(home, *this, x0, x1))); 194 return home.ES_NOFIX_PARTIAL(*this,View::med(ME_INT_DOM)); 195 } 196 197 Region r; 198 199 { 200 ViewRanges<View> i(x0), j(x0); 201 202 using namespace Iter::Ranges; 203 Positive<ViewRanges<View> > p(i); 204 Negative<ViewRanges<View> > n(j); 205 206 Minus m(r,n); 207 208 Union<Positive<ViewRanges<View> >,Minus> u(p,m); 209 210 GECODE_ME_CHECK(x1.inter_r(home,u,false)); 211 212 } 213 214 { 215 ViewRanges<View> i(x1), j(x1); 216 217 using namespace Iter::Ranges; 218 Minus m(r,j); 219 220 Union<ViewRanges<View>,Minus> u(i,m); 221 222 GECODE_ME_CHECK(x0.inter_r(home,u,false)); 223 } 224 225 if (x1.assigned()) 226 return home.ES_SUBSUMED(*this); 227 228 if (x0.min() >= 0) 229 GECODE_REWRITE(*this,(Rel::EqDom<View,View>::post(home(*this),x0,x1))); 230 231 if (x0.max() <= 0) { 232 MinusView mx0(x0); 233 GECODE_REWRITE(*this,(Rel::EqDom<MinusView,View>::post(home(*this),mx0,x1))); 234 } 235 236 return ES_FIX; 237 } 238 239 }}} 240 241 // STATISTICS: int-prop 242 243