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.constraints.pb;
31
32 import java.math.BigInteger;
33
34 public final class ConflictMapClause extends ConflictMap {
35
36 public ConflictMapClause(PBConstr cpb, int level) {
37 super(cpb, level);
38 }
39
40 public static IConflict createConflict(PBConstr cpb, int level) {
41 return new ConflictMapClause(cpb, level);
42 }
43
44 /**
45 * reduces the constraint defined by wpb until the result of the cutting
46 * plane is a conflict. this reduction returns a clause.
47 *
48 * @param litImplied
49 * @param ind
50 * @param reducedCoefs
51 * @param wpb
52 * @return BigInteger.ONE
53 */
54 @Override
55 protected BigInteger reduceUntilConflict(int litImplied, int ind,
56 BigInteger[] reducedCoefs, IWatchPb wpb) {
57 for (int i = 0; i < reducedCoefs.length; i++) {
58 if (i == ind || wpb.getVocabulary().isFalsified(wpb.get(i))) {
59 reducedCoefs[i] = BigInteger.ONE;
60 } else {
61 reducedCoefs[i] = BigInteger.ZERO;
62 }
63 }
64 this.coefMultCons = this.weightedLits.get(litImplied ^ 1);
65 this.coefMult = BigInteger.ONE;
66 return BigInteger.ONE;
67 }
68 }