1 /*
2 * SAT4J: a SATisfiability library for Java Copyright (C) 2004-2006 Daniel Le Berre
3 *
4 * Based on the original minisat specification from:
5 *
6 * An extensible SAT solver. Niklas E?n and Niklas S?rensson. Proceedings of the
7 * Sixth International Conference on Theory and Applications of Satisfiability
8 * Testing, LNCS 2919, pp 502-518, 2003.
9 *
10 * This library is free software; you can redistribute it and/or modify it under
11 * the terms of the GNU Lesser General Public License as published by the Free
12 * Software Foundation; either version 2.1 of the License, or (at your option)
13 * any later version.
14 *
15 * This library is distributed in the hope that it will be useful, but WITHOUT
16 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
17 * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
18 * details.
19 *
20 * You should have received a copy of the GNU Lesser General Public License
21 * along with this library; if not, write to the Free Software Foundation, Inc.,
22 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 *
24 */
25
26 package org.sat4j.opt;
27
28 import org.sat4j.core.VecInt;
29 import org.sat4j.specs.ContradictionException;
30 import org.sat4j.specs.IConstr;
31 import org.sat4j.specs.IOptimizationProblem;
32 import org.sat4j.specs.ISolver;
33 import org.sat4j.specs.IVecInt;
34
35 public class MaxSatDecorator extends AbstractSelectorVariablesDecorator
36 implements IOptimizationProblem {
37
38 /**
39 *
40 */
41 private static final long serialVersionUID = 1L;
42
43 // private IConstr prevconstr=null;
44
45 public MaxSatDecorator(ISolver solver) {
46 super(solver);
47 }
48
49 @Override
50 public IConstr addClause(IVecInt literals) throws ContradictionException {
51 literals.push(nborigvars + ++nbnewvar);
52 return super.addClause(literals);
53 }
54
55 @Override
56 public void reset() {
57 nbnewvar = 0;
58 vec.clear();
59 super.reset();
60 }
61
62 public boolean hasNoObjectiveFunction() {
63 return false;
64 }
65
66 public boolean nonOptimalMeansSatisfiable() {
67 return false;
68 }
69
70 public Number calculateObjective() {
71 counter = 0;
72 for (int q : prevfullmodel) {
73 if (q > nborigvars) {
74 counter++;
75 }
76 }
77 return counter;
78 }
79
80 private final IVecInt vec = new VecInt();
81
82 private int counter;
83
84 public void discard() throws ContradictionException {
85 if (vec.isEmpty()) {
86 for (int i = nborigvars + 1; i <= nVars(); i++) {
87 vec.push(i);
88 }
89 }
90 // if (prevconstr!=null)
91 // super.removeConstr(prevconstr);
92 // prevconstr =
93 super.addAtMost(vec, counter - 1);
94 }
95
96 }