1 /*******************************************************************************
2 * SAT4J: a SATisfiability library for Java Copyright (C) 2004-2008 Daniel Le Berre
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 *******************************************************************************/
28 package org.sat4j.pb.constraints.pb;
29
30 import java.math.BigInteger;
31
32 import org.sat4j.minisat.constraints.cnf.LearntHTClause;
33 import org.sat4j.minisat.core.ILits;
34 import org.sat4j.minisat.core.UnitPropagationListener;
35 import org.sat4j.specs.IVecInt;
36
37 public final class LearntHTClausePB extends LearntHTClause implements PBConstr {
38
39 private static final long serialVersionUID = 1L;
40
41 public LearntHTClausePB(IVecInt ps, ILits voc) {
42 super(ps, voc);
43 }
44
45 @Override
46 public void assertConstraint(UnitPropagationListener s) {
47 if (getVocabulary().isUnassigned(head)) {
48 s.enqueue(head, this);
49 } else if (getVocabulary().isUnassigned(tail)) {
50 s.enqueue(tail, this);
51 } else {
52 for (int i = 0; i < middleLits.length; i++) {
53 if (getVocabulary().isUnassigned(middleLits[i])) {
54 int temp = middleLits[i];
55 middleLits[i] = head;
56 head = temp;
57 s.enqueue(temp, this);
58 break;
59 }
60 }
61 }
62 }
63
64 public IVecInt computeAnImpliedClause() {
65 return null;
66 }
67
68 public BigInteger getCoef(int literal) {
69 return BigInteger.ONE;
70 }
71
72 public BigInteger[] getCoefs() {
73 BigInteger[] tmp = new BigInteger[size()];
74 for (int i = 0; i < tmp.length; i++)
75 tmp[i] = BigInteger.ONE;
76 return tmp;
77 }
78
79 public BigInteger getDegree() {
80 return BigInteger.ONE;
81 }
82
83 }