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 package org.sat4j.csp;
20
21 import org.sat4j.core.VecInt;
22 import org.sat4j.specs.ContradictionException;
23 import org.sat4j.specs.ISolver;
24 import org.sat4j.specs.IVecInt;
25
26 public class Var implements Evaluable {
27
28 private final Domain domain;
29
30 private final String id;
31
32 private final int startid;
33
34 public Var(String idvar, Domain domain, int lastvarnumber) {
35 this.domain = domain;
36 this.id = idvar;
37 this.startid = lastvarnumber + 1;
38 }
39
40 /*
41 * (non-Javadoc)
42 *
43 * @see org.sat4j.reader.csp.Evaluable#domain()
44 */
45 public Domain domain() {
46 return domain;
47 }
48
49 /*
50 * (non-Javadoc)
51 *
52 * @see org.sat4j.reader.csp.Evaluable#translate(int)
53 */
54 public int translate(int key) {
55 return domain.pos(key) + startid;
56 }
57
58 /*
59 * (non-Javadoc)
60 *
61 * @see org.sat4j.reader.csp.Evaluable#toClause(org.sat4j.specs.ISolver)
62 */
63 public void toClause(ISolver solver) throws ContradictionException {
64 IVecInt clause = new VecInt(domain.size());
65 for (int i = 0; i < domain.size(); i++)
66 clause.push(i + startid);
67 solver.addClause(clause);
68 solver.addAtMost(clause, 1);
69 }
70
71 public int findValue(int[] model) {
72 for (int i = 0; i < domain.size(); i++) {
73 int varnum = i + startid;
74 if (model[varnum - 1] == varnum)
75 return domain.get(i);
76 }
77 throw new RuntimeException("BIG PROBLEM: no value for a var!");
78 }
79
80 /*
81 * (non-Javadoc)
82 *
83 * @see java.lang.Object#toString()
84 */
85 @Override
86 public String toString() {
87 return id;
88 }
89
90 }