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 pseudo boolean algorithms described in:
20 * A fast pseudo-Boolean constraint solver Chai, D.; Kuehlmann, A.
21 * Computer-Aided Design of Integrated Circuits and Systems, IEEE Transactions on
22 * Volume 24, Issue 3, March 2005 Page(s): 305 - 317
23 *
24 * and
25 * Heidi E. Dixon, 2004. Automating Pseudo-Boolean Inference within a DPLL
26 * Framework. Ph.D. Dissertation, University of Oregon.
27 *******************************************************************************/
28 package org.sat4j.pb.constraints.pb;
29
30 import java.math.BigInteger;
31
32 import org.sat4j.minisat.constraints.cnf.MixableCBClause;
33 import org.sat4j.minisat.core.ILits;
34 import org.sat4j.minisat.core.UnitPropagationListener;
35 import org.sat4j.specs.IVecInt;
36
37 public class MixableCBClausePB extends MixableCBClause implements PBConstr {
38
39 /**
40 *
41 */
42 private static final long serialVersionUID = 1L;
43
44 public MixableCBClausePB(IVecInt ps, ILits voc, boolean learnt) {
45 super(ps, voc, learnt);
46 }
47
48 public MixableCBClausePB(IVecInt ps, ILits voc) {
49 super(ps, voc);
50 }
51
52 public static MixableCBClausePB brandNewClause(UnitPropagationListener s,
53 ILits voc, IVecInt literals) {
54 MixableCBClausePB c = new MixableCBClausePB(literals, voc);
55 c.register();
56 return c;
57 }
58
59 /*
60 * (non-Javadoc)
61 *
62 * @see org.sat4j.minisat.constraints.pb.PBConstr#computeAnImpliedClause()
63 */
64 public IVecInt computeAnImpliedClause() {
65 return null;
66 }
67
68 /*
69 * (non-Javadoc)
70 *
71 * @see org.sat4j.minisat.constraints.pb.PBConstr#getCoef(int)
72 */
73 public BigInteger getCoef(int literal) {
74 return BigInteger.ONE;
75 }
76
77 /*
78 * (non-Javadoc)
79 *
80 * @see org.sat4j.minisat.constraints.pb.PBConstr#getCoefs()
81 */
82 public BigInteger[] getCoefs() {
83 BigInteger[] tmp = new BigInteger[size()];
84 for (int i = 0; i < tmp.length; i++)
85 tmp[i] = BigInteger.ONE;
86 return tmp;
87 }
88
89 /*
90 * (non-Javadoc)
91 *
92 * @see org.sat4j.minisat.constraints.pb.PBConstr#getDegree()
93 */
94 public BigInteger getDegree() {
95 return BigInteger.ONE;
96 }
97
98 /*
99 * (non-Javadoc)
100 *
101 * @see org.sat4j.minisat.constraints.pb.PBConstr#getLits()
102 */
103 public int[] getLits() {
104 int[] tmp = new int[size()];
105 System.arraycopy(lits, 0, tmp, 0, size());
106 return tmp;
107 }
108
109 /*
110 * (non-Javadoc)
111 *
112 * @see org.sat4j.minisat.constraints.pb.PBConstr#getVocabulary()
113 */
114 public ILits getVocabulary() {
115 return voc;
116 }
117
118 /*
119 * (non-Javadoc)
120 *
121 * @see org.sat4j.minisat.core.Constr#assertConstraint(org.sat4j.minisat.core.UnitPropagationListener)
122 */
123 @Override
124 public void assertConstraint(UnitPropagationListener s) {
125 for (int i = 0; i < size(); i++)
126 if (getVocabulary().isUnassigned(get(i))) {
127 boolean ret = s.enqueue(get(i), this);
128 assert ret;
129 break;
130 }
131 }
132
133 }