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-rw-r--r--src/jrummikub/ai/fdsolver/constraint/ComparatorConstraint.java39
1 files changed, 23 insertions, 16 deletions
diff --git a/src/jrummikub/ai/fdsolver/constraint/ComparatorConstraint.java b/src/jrummikub/ai/fdsolver/constraint/ComparatorConstraint.java
index ab0edde..019de92 100644
--- a/src/jrummikub/ai/fdsolver/constraint/ComparatorConstraint.java
+++ b/src/jrummikub/ai/fdsolver/constraint/ComparatorConstraint.java
@@ -6,6 +6,7 @@ import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
+import java.util.NoSuchElementException;
import jrummikub.ai.fdsolver.Constraint;
import jrummikub.ai.fdsolver.Propagator;
@@ -17,8 +18,9 @@ public class ComparatorConstraint<T> extends Constraint {
Comparator<T> comparator, reverseComparator;
ComparatorPropagator<T> trueX, trueY, falseX, falseY;
boolean allowEqual;
-
- ComparatorConstraint(final Comparator<T> comparator, boolean allowEqual, Var<T> x, Var<T> y) {
+
+ ComparatorConstraint(final Comparator<T> comparator, boolean allowEqual,
+ Var<T> x, Var<T> y) {
this.x = x;
this.y = y;
this.comparator = comparator;
@@ -31,37 +33,42 @@ public class ComparatorConstraint<T> extends Constraint {
};
trueX = new ComparatorPropagator<T>(comparator, allowEqual, x, y);
trueY = new ComparatorPropagator<T>(reverseComparator, allowEqual, y, x);
- falseX = new ComparatorPropagator<T>(reverseComparator, !allowEqual, x, y);
+ falseX = new ComparatorPropagator<T>(reverseComparator, !allowEqual, x,
+ y);
falseY = new ComparatorPropagator<T>(comparator, !allowEqual, y, x);
}
-
+
@Override
public Collection<Var<?>> getWatchedVars() {
- return Arrays.<Var<?>>asList(x,y);
+ return Arrays.<Var<?>> asList(x, y);
}
@Override
public Collection<Propagator> getPropagators(boolean negate) {
if (negate) {
- return Arrays.<Propagator>asList(falseX,falseY);
+ return Arrays.<Propagator> asList(falseX, falseY);
} else {
- return Arrays.<Propagator>asList(trueX,trueY);
+ return Arrays.<Propagator> asList(trueX, trueY);
}
}
@Override
public Satisfiability getSatisfiability() {
- T maxX = Collections.max(x.getRange(), comparator);
- T minY = Collections.min(y.getRange(), comparator);
- if (comparator.compare(maxX, minY) < (allowEqual ? 1 : 0)) {
- return TAUT;
- }
- T minX = Collections.min(x.getRange(), comparator);
- T maxY = Collections.max(y.getRange(), comparator);
- if (comparator.compare(maxY, minX) < (allowEqual ? 0 : 1)) {
+ try {
+ T maxX = Collections.max(x.getRange(), comparator);
+ T minY = Collections.min(y.getRange(), comparator);
+ if (comparator.compare(maxX, minY) < (allowEqual ? 1 : 0)) {
+ return TAUT;
+ }
+ T minX = Collections.min(x.getRange(), comparator);
+ T maxY = Collections.max(y.getRange(), comparator);
+ if (comparator.compare(maxY, minX) < (allowEqual ? 0 : 1)) {
+ return UNSAT;
+ }
+ return SAT;
+ } catch (NoSuchElementException e) {
return UNSAT;
}
- return SAT;
}
}