1 /*******************************************************************************
2 * SAT4J: a SATisfiability library for Java Copyright (C) 2004, 2012 Artois University and CNRS
3 *
4 * All rights reserved. This program and the accompanying materials
5 * are made available under the terms of the Eclipse Public License v1.0
6 * which accompanies this distribution, and is available at
7 * http://www.eclipse.org/legal/epl-v10.html
8 *
9 * Alternatively, the contents of this file may be used under the terms of
10 * either the GNU Lesser General Public License Version 2.1 or later (the
11 * "LGPL"), in which case the provisions of the LGPL are applicable instead
12 * of those above. If you wish to allow use of your version of this file only
13 * under the terms of the LGPL, and not to allow others to use your version of
14 * this file under the terms of the EPL, indicate your decision by deleting
15 * the provisions above and replace them with the notice and other provisions
16 * required by the LGPL. If you do not delete the provisions above, a recipient
17 * may use your version of this file under the terms of the EPL or the LGPL.
18 *
19 * Based on the original MiniSat specification from:
20 *
21 * An extensible SAT solver. Niklas Een and Niklas Sorensson. Proceedings of the
22 * Sixth International Conference on Theory and Applications of Satisfiability
23 * Testing, LNCS 2919, pp 502-518, 2003.
24 *
25 * See www.minisat.se for the original solver in C++.
26 *
27 * Contributors:
28 * CRIL - initial API and implementation
29 *******************************************************************************/
30 package org.sat4j.pb.core;
31
32 import org.sat4j.minisat.core.IOrder;
33 import org.sat4j.minisat.core.LearningStrategy;
34 import org.sat4j.pb.constraints.pb.ConflictMapSwitchToClause;
35 import org.sat4j.pb.constraints.pb.IConflict;
36 import org.sat4j.pb.constraints.pb.PBConstr;
37
38 public class PBSolverCautious extends PBSolverCP {
39
40 private static final long serialVersionUID = 1L;
41 public static final int BOUND = 10;
42
43 public PBSolverCautious(LearningStrategy<PBDataStructureFactory> learner,
44 PBDataStructureFactory dsf, IOrder order) {
45 super(learner, dsf, order);
46 ConflictMapSwitchToClause.UPPERBOUND = BOUND;
47 }
48
49 public PBSolverCautious(LearningStrategy<PBDataStructureFactory> learner,
50 PBDataStructureFactory dsf, IOrder order, int bound) {
51 super(learner, dsf, order);
52 ConflictMapSwitchToClause.UPPERBOUND = bound;
53 }
54
55 @Override
56 IConflict chooseConflict(PBConstr myconfl, int level) {
57 return ConflictMapSwitchToClause.createConflict(myconfl, level);
58 }
59
60 @Override
61 public String toString(String prefix) {
62 return super.toString(prefix)
63 + "\n"
64 + prefix
65 + "When dealing with too large coefficients, simplify asserted PB constraints to clauses";
66 }
67
68 @Override
69 protected void updateNumberOfReductions(IConflict confl) {
70 this.stats.numberOfReductions += ((ConflictMapSwitchToClause) confl)
71 .getNumberOfReductions();
72 }
73
74 @Override
75 protected void updateNumberOfReducedLearnedConstraints(IConflict confl) {
76 if (((ConflictMapSwitchToClause) confl).hasBeenReduced()) {
77 this.stats.numberOfLearnedConstraintsReduced++;
78 }
79 }
80
81 }