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.minisat.restarts;
29
30 import org.sat4j.minisat.core.RestartStrategy;
31 import org.sat4j.minisat.core.SearchParams;
32
33 /**
34 * Minisat original restart strategy.
35 *
36 * @author leberre
37 *
38 */
39 public class MiniSATRestarts implements RestartStrategy {
40
41 /**
42 *
43 */
44 private static final long serialVersionUID = 1L;
45
46 private double nofConflicts;
47
48 private SearchParams params;
49
50 public void init(SearchParams theParams) {
51 this.params = theParams;
52 nofConflicts = theParams.getInitConflictBound();
53 }
54
55 public long nextRestartNumberOfConflict() {
56 return Math.round(nofConflicts);
57 }
58
59 public void onRestart() {
60 nofConflicts *= params.getConflictBoundIncFactor();
61 }
62
63 @Override
64 public String toString() {
65 return "MiniSAT restarts strategy";
66 }
67 }