this repo has no description
dekker.one
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, 2004
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#include <cmath>
35#include <climits>
36
37#include <gecode/int/div.hh>
38#include <gecode/int/support-values.hh>
39
40namespace Gecode { namespace Int { namespace Arithmetic {
41
42 /*
43 * Arithmetic help functions
44 *
45 */
46 /// Multiply \a x and \y
47 forceinline long long int
48 mll(long long int x, long long int y) {
49 return x*y;
50 }
51 /// Cast \a x into a long long int
52 forceinline long long int
53 ll(int x) {
54 return static_cast<long long int>(x);
55 }
56 /// Increment \a x by one
57 forceinline long long int
58 ill(int x) {
59 return static_cast<long long int>(x) + 1;
60 }
61 /// Decrement \a x by one
62 forceinline long long int
63 dll(int x) {
64 return static_cast<long long int>(x) - 1;
65 }
66
67 /// Test whether \a x is postive
68 template<class View>
69 forceinline bool
70 pos(const View& x) {
71 return x.min() > 0;
72 }
73 /// Test whether \a x is negative
74 template<class View>
75 forceinline bool
76 neg(const View& x) {
77 return x.max() < 0;
78 }
79 /// Test whether \a x is neither positive nor negative
80 template<class View>
81 forceinline bool
82 any(const View& x) {
83 return (x.min() <= 0) && (x.max() >= 0);
84 }
85
86
87 /*
88 * Propagator for x * y = x
89 *
90 */
91
92 template<class View, PropCond pc>
93 forceinline
94 MultZeroOne<View,pc>::MultZeroOne(Home home, View x0, View x1)
95 : BinaryPropagator<View,pc>(home,x0,x1) {}
96
97 template<class View, PropCond pc>
98 forceinline RelTest
99 MultZeroOne<View,pc>::equal(View x, int n) {
100 if (pc == PC_INT_DOM) {
101 return rtest_eq_dom(x,n);
102 } else {
103 return rtest_eq_bnd(x,n);
104 }
105 }
106
107 template<class View, PropCond pc>
108 forceinline ExecStatus
109 MultZeroOne<View,pc>::post(Home home, View x0, View x1) {
110 switch (equal(x0,0)) {
111 case RT_FALSE:
112 GECODE_ME_CHECK(x1.eq(home,1));
113 break;
114 case RT_TRUE:
115 break;
116 case RT_MAYBE:
117 switch (equal(x1,1)) {
118 case RT_FALSE:
119 GECODE_ME_CHECK(x0.eq(home,0));
120 break;
121 case RT_TRUE:
122 break;
123 case RT_MAYBE:
124 (void) new (home) MultZeroOne<View,pc>(home,x0,x1);
125 break;
126 default: GECODE_NEVER;
127 }
128 break;
129 default: GECODE_NEVER;
130 }
131 return ES_OK;
132 }
133
134 template<class View, PropCond pc>
135 forceinline
136 MultZeroOne<View,pc>::MultZeroOne(Space& home, MultZeroOne<View,pc>& p)
137 : BinaryPropagator<View,pc>(home,p) {}
138
139 template<class View, PropCond pc>
140 Actor*
141 MultZeroOne<View,pc>::copy(Space& home) {
142 return new (home) MultZeroOne<View,pc>(home,*this);
143 }
144
145 template<class View, PropCond pc>
146 ExecStatus
147 MultZeroOne<View,pc>::propagate(Space& home, const ModEventDelta&) {
148 switch (equal(x0,0)) {
149 case RT_FALSE:
150 GECODE_ME_CHECK(x1.eq(home,1));
151 break;
152 case RT_TRUE:
153 break;
154 case RT_MAYBE:
155 switch (equal(x1,1)) {
156 case RT_FALSE:
157 GECODE_ME_CHECK(x0.eq(home,0));
158 break;
159 case RT_TRUE:
160 break;
161 case RT_MAYBE:
162 return ES_FIX;
163 default: GECODE_NEVER;
164 }
165 break;
166 default: GECODE_NEVER;
167 }
168 return home.ES_SUBSUMED(*this);
169 }
170
171
172 /*
173 * Positive bounds consistent multiplication
174 *
175 */
176 template<class VA, class VB, class VC>
177 forceinline ExecStatus
178 prop_mult_plus_bnd(Space& home, Propagator& p, VA x0, VB x1, VC x2) {
179 assert(pos(x0) && pos(x1) && pos(x2));
180 bool mod;
181 do {
182 mod = false;
183 {
184 ModEvent me = x2.lq(home,mll(x0.max(),x1.max()));
185 if (me_failed(me)) return ES_FAILED;
186 mod |= me_modified(me);
187 }
188 {
189 ModEvent me = x2.gq(home,mll(x0.min(),x1.min()));
190 if (me_failed(me)) return ES_FAILED;
191 mod |= me_modified(me);
192 }
193 {
194 ModEvent me = x0.lq(home,floor_div_pp(x2.max(),x1.min()));
195 if (me_failed(me)) return ES_FAILED;
196 mod |= me_modified(me);
197 }
198 {
199 ModEvent me = x0.gq(home,ceil_div_pp(x2.min(),x1.max()));
200 if (me_failed(me)) return ES_FAILED;
201 mod |= me_modified(me);
202 }
203 {
204 ModEvent me = x1.lq(home,floor_div_pp(x2.max(),x0.min()));
205 if (me_failed(me)) return ES_FAILED;
206 mod |= me_modified(me);
207 }
208 {
209 ModEvent me = x1.gq(home,ceil_div_pp(x2.min(),x0.max()));
210 if (me_failed(me)) return ES_FAILED;
211 mod |= me_modified(me);
212 }
213 } while (mod);
214 return x0.assigned() && x1.assigned() ?
215 home.ES_SUBSUMED(p) : ES_FIX;
216 }
217
218 template<class VA, class VB, class VC>
219 forceinline
220 MultPlusBnd<VA,VB,VC>::MultPlusBnd(Home home, VA x0, VB x1, VC x2)
221 : MixTernaryPropagator<VA,PC_INT_BND,VB,PC_INT_BND,VC,PC_INT_BND>
222 (home,x0,x1,x2) {}
223
224 template<class VA, class VB, class VC>
225 forceinline
226 MultPlusBnd<VA,VB,VC>::MultPlusBnd(Space& home, MultPlusBnd<VA,VB,VC>& p)
227 : MixTernaryPropagator<VA,PC_INT_BND,VB,PC_INT_BND,VC,PC_INT_BND>
228 (home,p) {}
229
230 template<class VA, class VB, class VC>
231 Actor*
232 MultPlusBnd<VA,VB,VC>::copy(Space& home) {
233 return new (home) MultPlusBnd<VA,VB,VC>(home,*this);
234 }
235
236 template<class VA, class VB, class VC>
237 ExecStatus
238 MultPlusBnd<VA,VB,VC>::propagate(Space& home, const ModEventDelta&) {
239 return prop_mult_plus_bnd<VA,VB,VC>(home,*this,x0,x1,x2);
240 }
241
242 template<class VA, class VB, class VC>
243 forceinline ExecStatus
244 MultPlusBnd<VA,VB,VC>::post(Home home, VA x0, VB x1, VC x2) {
245 GECODE_ME_CHECK(x0.gr(home,0));
246 GECODE_ME_CHECK(x1.gr(home,0));
247 GECODE_ME_CHECK(x2.gq(home,mll(x0.min(),x1.min())));
248 GECODE_ME_CHECK(x2.lq(home,mll(x0.max(),x1.max())));
249 (void) new (home) MultPlusBnd<VA,VB,VC>(home,x0,x1,x2);
250 return ES_OK;
251 }
252
253
254 /*
255 * Bounds consistent multiplication
256 *
257 */
258 forceinline
259 MultBnd::MultBnd(Home home, IntView x0, IntView x1, IntView x2)
260 : TernaryPropagator<IntView,PC_INT_BND>(home,x0,x1,x2) {}
261
262 forceinline
263 MultBnd::MultBnd(Space& home, MultBnd& p)
264 : TernaryPropagator<IntView,PC_INT_BND>(home,p) {}
265
266 /*
267 * Positive domain consistent multiplication
268 *
269 */
270 template<class View>
271 forceinline ExecStatus
272 prop_mult_dom(Space& home, Propagator& p, View x0, View x1, View x2) {
273 Region r;
274 SupportValues<View,Region> s0(r,x0), s1(r,x1), s2(r,x2);
275 while (s0()) {
276 while (s1()) {
277 if (s2.support(mll(s0.val(),s1.val()))) {
278 s0.support(); s1.support();
279 }
280 ++s1;
281 }
282 s1.reset(); ++s0;
283 }
284 GECODE_ME_CHECK(s0.tell(home));
285 GECODE_ME_CHECK(s1.tell(home));
286 GECODE_ME_CHECK(s2.tell(home));
287 return x0.assigned() && x1.assigned() ? home.ES_SUBSUMED(p) : ES_FIX;
288 }
289
290 template<class VA, class VB, class VC>
291 forceinline
292 MultPlusDom<VA,VB,VC>::MultPlusDom(Home home, VA x0, VB x1, VC x2)
293 : MixTernaryPropagator<VA,PC_INT_DOM,VB,PC_INT_DOM,VC,PC_INT_DOM>
294 (home,x0,x1,x2) {}
295
296 template<class VA, class VB, class VC>
297 forceinline
298 MultPlusDom<VA,VB,VC>::MultPlusDom(Space& home, MultPlusDom<VA,VB,VC>& p)
299 : MixTernaryPropagator<VA,PC_INT_DOM,VB,PC_INT_DOM,VC,PC_INT_DOM>
300 (home,p) {}
301
302 template<class VA, class VB, class VC>
303 Actor*
304 MultPlusDom<VA,VB,VC>::copy(Space& home) {
305 return new (home) MultPlusDom<VA,VB,VC>(home,*this);
306 }
307
308 template<class VA, class VB, class VC>
309 PropCost
310 MultPlusDom<VA,VB,VC>::cost(const Space&,
311 const ModEventDelta& med) const {
312 if (VA::me(med) == ME_INT_DOM)
313 return PropCost::ternary(PropCost::HI);
314 else
315 return PropCost::ternary(PropCost::LO);
316 }
317
318 template<class VA, class VB, class VC>
319 ExecStatus
320 MultPlusDom<VA,VB,VC>::propagate(Space& home, const ModEventDelta& med) {
321 if (VA::me(med) != ME_INT_DOM) {
322 GECODE_ES_CHECK((prop_mult_plus_bnd<VA,VB,VC>(home,*this,x0,x1,x2)));
323 return home.ES_FIX_PARTIAL(*this,VA::med(ME_INT_DOM));
324 }
325 IntView y0(x0.varimp()), y1(x1.varimp()), y2(x2.varimp());
326 return prop_mult_dom<IntView>(home,*this,y0,y1,y2);
327 }
328
329 template<class VA, class VB, class VC>
330 forceinline ExecStatus
331 MultPlusDom<VA,VB,VC>::post(Home home, VA x0, VB x1, VC x2) {
332 GECODE_ME_CHECK(x0.gr(home,0));
333 GECODE_ME_CHECK(x1.gr(home,0));
334 GECODE_ME_CHECK(x2.gq(home,mll(x0.min(),x1.min())));
335 GECODE_ME_CHECK(x2.lq(home,mll(x0.max(),x1.max())));
336 (void) new (home) MultPlusDom<VA,VB,VC>(home,x0,x1,x2);
337 return ES_OK;
338 }
339
340
341 /*
342 * Domain consistent multiplication
343 *
344 */
345 forceinline
346 MultDom::MultDom(Home home, IntView x0, IntView x1, IntView x2)
347 : TernaryPropagator<IntView,PC_INT_DOM>(home,x0,x1,x2) {}
348
349 forceinline
350 MultDom::MultDom(Space& home, MultDom& p)
351 : TernaryPropagator<IntView,PC_INT_DOM>(home,p) {}
352
353}}}
354
355// STATISTICS: int-prop
356