|
1 |
| |
|
2 |
| |
|
3 |
| |
|
4 |
| |
|
5 |
| |
|
6 |
| |
|
7 |
| package org.sat4j.opt; |
|
8 |
| |
|
9 |
| import java.math.BigInteger; |
|
10 |
| |
|
11 |
| import org.sat4j.core.Vec; |
|
12 |
| import org.sat4j.core.VecInt; |
|
13 |
| import org.sat4j.specs.ContradictionException; |
|
14 |
| import org.sat4j.specs.IConstr; |
|
15 |
| import org.sat4j.specs.IOptimizationProblem; |
|
16 |
| import org.sat4j.specs.ISolver; |
|
17 |
| import org.sat4j.specs.IVec; |
|
18 |
| import org.sat4j.specs.IVecInt; |
|
19 |
| import org.sat4j.specs.TimeoutException; |
|
20 |
| import org.sat4j.tools.SolverDecorator; |
|
21 |
| |
|
22 |
| public class WeightedMaxSatDecorator extends SolverDecorator implements |
|
23 |
| IOptimizationProblem { |
|
24 |
| |
|
25 |
| |
|
26 |
| |
|
27 |
| |
|
28 |
| private static final long serialVersionUID = 1L; |
|
29 |
| |
|
30 |
| private int nborigvars; |
|
31 |
| |
|
32 |
| private int nbexpectedclauses; |
|
33 |
| |
|
34 |
| private int nbnewvar; |
|
35 |
| |
|
36 |
| private final IVec<BigInteger> coefs = new Vec<BigInteger>(); |
|
37 |
| |
|
38 |
| private int[] prevfullmodel; |
|
39 |
| |
|
40 |
0
| public WeightedMaxSatDecorator(ISolver solver) {
|
|
41 |
0
| super(solver);
|
|
42 |
| } |
|
43 |
| |
|
44 |
0
| @Override
|
|
45 |
| public int[] model() { |
|
46 |
0
| prevfullmodel = super.model();
|
|
47 |
0
| int[] shortmodel = new int[nborigvars];
|
|
48 |
0
| for (int i = 0; i < nborigvars; i++) {
|
|
49 |
0
| shortmodel[i] = prevfullmodel[i];
|
|
50 |
| } |
|
51 |
0
| return shortmodel;
|
|
52 |
| } |
|
53 |
| |
|
54 |
0
| @Override
|
|
55 |
| public int newVar(int howmany) { |
|
56 |
0
| nborigvars = super.newVar(howmany);
|
|
57 |
0
| return nborigvars;
|
|
58 |
| } |
|
59 |
| |
|
60 |
0
| @Override
|
|
61 |
| public void setExpectedNumberOfClauses(int nb) { |
|
62 |
0
| nbexpectedclauses = nb;
|
|
63 |
0
| super.setExpectedNumberOfClauses(nb);
|
|
64 |
0
| super.newVar(nborigvars + nbexpectedclauses);
|
|
65 |
| } |
|
66 |
| |
|
67 |
0
| @Override
|
|
68 |
| public IConstr addClause(IVecInt literals) throws ContradictionException { |
|
69 |
| |
|
70 |
0
| coefs.push(BigInteger.valueOf(literals.get(0)));
|
|
71 |
0
| literals.set(0, nborigvars + ++nbnewvar);
|
|
72 |
0
| return super.addClause(literals);
|
|
73 |
| } |
|
74 |
| |
|
75 |
0
| @Override
|
|
76 |
| public void reset() { |
|
77 |
0
| nbnewvar = 0;
|
|
78 |
0
| coefs.clear();
|
|
79 |
0
| vec.clear();
|
|
80 |
0
| super.reset();
|
|
81 |
| } |
|
82 |
| |
|
83 |
0
| public boolean admitABetterSolution() throws TimeoutException {
|
|
84 |
0
| boolean result = super.isSatisfiable();
|
|
85 |
0
| if (result)
|
|
86 |
0
| prevfullmodel = super.model();
|
|
87 |
0
| return result;
|
|
88 |
| } |
|
89 |
| |
|
90 |
0
| public boolean hasNoObjectiveFunction() {
|
|
91 |
0
| return false;
|
|
92 |
| } |
|
93 |
| |
|
94 |
0
| public boolean nonOptimalMeansSatisfiable() {
|
|
95 |
0
| return false;
|
|
96 |
| } |
|
97 |
| |
|
98 |
| private BigInteger counter; |
|
99 |
| |
|
100 |
0
| public Number calculateObjective() {
|
|
101 |
0
| counter = BigInteger.ZERO;
|
|
102 |
0
| for (int q : prevfullmodel) {
|
|
103 |
0
| if (q > nborigvars) {
|
|
104 |
0
| counter = counter.add(coefs.get(q - nborigvars - 1));
|
|
105 |
| } |
|
106 |
| } |
|
107 |
0
| return counter;
|
|
108 |
| } |
|
109 |
| |
|
110 |
| private final IVecInt vec = new VecInt(); |
|
111 |
| |
|
112 |
0
| public void discard() throws ContradictionException {
|
|
113 |
0
| if (vec.isEmpty()) {
|
|
114 |
0
| for (int i = nborigvars + 1; i <= nVars(); i++) {
|
|
115 |
0
| vec.push(i);
|
|
116 |
| } |
|
117 |
| } |
|
118 |
0
| super.addPseudoBoolean(vec, coefs, false, counter
|
|
119 |
| .subtract(BigInteger.ONE)); |
|
120 |
| } |
|
121 |
| |
|
122 |
| } |
