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| package org.sat4j.reader.csp; |
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| |
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| import org.sat4j.core.VecInt; |
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| import org.sat4j.specs.ContradictionException; |
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| import org.sat4j.specs.ISolver; |
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| import org.sat4j.specs.IVecInt; |
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| |
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| |
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| public class SupportsDirectEncoding implements Relation { |
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| |
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| protected final int[] domains; |
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| |
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| protected int[][] tuples; |
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| |
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| private IVecInt clause; |
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| private int lastmatch; |
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| |
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0
| public SupportsDirectEncoding(int[] domains, int nbtuples) {
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19 |
0
| this.domains = domains;
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| tuples = new int[nbtuples][];
|
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| } |
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| |
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0
| public void addTuple(int index, int[] tuple) {
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| tuples[index] = tuple;
|
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| } |
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| |
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0
| public void toClause(ISolver solver, Var[] vars)
|
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| throws ContradictionException { |
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| |
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0
| clause = new VecInt();
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| int[] tuple = new int[vars.length];
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32 |
0
| lastmatch=-1;
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0
| find(tuple, 0, vars, solver);
|
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| } |
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| |
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| private void find(int[] tuple, int n, Var[] vars, ISolver solver)
|
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| throws ContradictionException { |
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0
| if (n == vars.length) {
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39 |
0
| if (notPresent(tuple)) {
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| clause.clear();
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| for (int j = 0; j < vars.length; j++) {
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| clause.push(-vars[j].translate(tuple[j]));
|
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| } |
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| |
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| solver.addClause(clause);
|
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| } |
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| } else { |
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0
| int[] domain = vars[n].domain();
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| for (int i = 0; i < domain.length; i++) {
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50 |
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| tuple[n] = domain[i];
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| find(tuple, n + 1, vars, solver);
|
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| } |
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| |
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| } |
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| |
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| } |
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| |
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0
| private boolean notPresent(int[] tuple) {
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| |
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| |
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| |
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| int i = lastmatch+1;
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| int j = 0;
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64 |
0
| while (i<tuples.length&&j < tuple.length) {
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65 |
0
| if (tuples[i][j] < tuple[j]) {
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| i++;
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| j = 0;
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| continue;
|
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| } |
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0
| if (tuples[i][j] > tuple[j])
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| return true;
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| j++;
|
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| } |
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0
| if (j==tuple.length) {
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| lastmatch=i;
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| return false;
|
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| } |
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| return true;
|
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| } |
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| |
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0
| public int arity() {
|
82 |
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| return domains.length;
|
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| } |
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| } |