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;
29
30 import java.math.BigInteger;
31
32 import org.sat4j.specs.ContradictionException;
33 import org.sat4j.specs.IConstr;
34 import org.sat4j.specs.ISolver;
35 import org.sat4j.specs.IVec;
36 import org.sat4j.specs.IVecInt;
37
38 /**
39 * A solver able to deal with pseudo boolean constraints.
40 *
41 * @author daniel
42 *
43 */
44 public interface IPBSolver extends ISolver {
45
46 /**
47 * Create a Pseudo-Boolean constraint of the type "at least n of those
48 * literals must be satisfied"
49 *
50 * @param lits
51 * a set of literals. The vector can be reused since the solver
52 * is not supposed to keep a reference to that vector.
53 * @param coeffs
54 * the coefficients of the literals. The vector can be reused
55 * since the solver is not supposed to keep a reference to that
56 * vector.
57 * @param moreThan
58 * true if it is a constraint >= degree
59 * @param d
60 * the degree of the cardinality constraint
61 * @return a reference to the constraint added in the solver, to use in
62 * removeConstr().
63 * @throws ContradictionException
64 * iff the vector of literals is empty or if the constraint is
65 * falsified after unit propagation
66 * @see #removeConstr(IConstr)
67 */
68 IConstr addPseudoBoolean(IVecInt lits, IVec<BigInteger> coeffs,
69 boolean moreThan, BigInteger d) throws ContradictionException;
70
71
72 public void setListOfVariablesForExplanation(IVecInt listOfVariables);
73
74 public String getExplanation();
75
76 public void setObjectiveFunction(ObjectiveFunction obj);
77 }