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.maxsat.reader;
20
21 import java.io.IOException;
22 import java.io.LineNumberReader;
23 import java.util.StringTokenizer;
24
25 import org.sat4j.maxsat.WeightedMaxSatDecorator;
26 import org.sat4j.pb.IPBSolver;
27 import org.sat4j.reader.DimacsReader;
28 import org.sat4j.reader.ParseFormatException;
29
30 /**
31 * Simple reader for the weighted maxsat problem.
32 *
33 * @author daniel
34 *
35 */
36 public class WDimacsReader extends DimacsReader {
37
38 /**
39 *
40 */
41 private static final long serialVersionUID = 1L;
42
43 public WDimacsReader(IPBSolver solver) {
44 super(solver,"wcnf");
45 }
46
47 public WDimacsReader(IPBSolver solver, String format) {
48 super(solver, format);
49 }
50
51 @Override
52 protected void readProblemLine(LineNumberReader in) throws IOException,
53 ParseFormatException {
54 String line = in.readLine();
55
56 if (line == null) {
57 throw new ParseFormatException(
58 "premature end of file: <p cnf ...> expected on line "
59 + in.getLineNumber());
60 }
61 StringTokenizer stk = new StringTokenizer(line);
62
63 if (!(stk.hasMoreTokens() && stk.nextToken().equals("p")
64 && stk.hasMoreTokens() && stk.nextToken().equals(formatString))) {
65 throw new ParseFormatException(
66 "problem line expected (p cnf ...) on line "
67 + in.getLineNumber());
68 }
69
70 int vars;
71
72 // reads the max var id
73 vars = Integer.parseInt(stk.nextToken());
74 assert vars > 0;
75 solver.newVar(vars);
76 // reads the number of clauses
77 expectedNbOfConstr = Integer.parseInt(stk.nextToken());
78 assert expectedNbOfConstr > 0;
79 solver.setExpectedNumberOfClauses(expectedNbOfConstr);
80
81 if ("wcnf".equals(formatString)) {
82 // assume we are in weighted MAXSAT mode
83 int top;
84 if (stk.hasMoreTokens()) {
85 top = Integer.parseInt(stk.nextToken());
86 } else {
87 top = Integer.MAX_VALUE;
88 }
89 ((WeightedMaxSatDecorator)solver).setTopWeight(top);
90 }
91 }
92
93
94 }