summaryrefslogtreecommitdiffstats
path: root/src/jrummikub/ai/fdsolver/constraint/SameConstraint.java
diff options
context:
space:
mode:
Diffstat (limited to 'src/jrummikub/ai/fdsolver/constraint/SameConstraint.java')
-rw-r--r--src/jrummikub/ai/fdsolver/constraint/SameConstraint.java5
1 files changed, 2 insertions, 3 deletions
diff --git a/src/jrummikub/ai/fdsolver/constraint/SameConstraint.java b/src/jrummikub/ai/fdsolver/constraint/SameConstraint.java
index 954b6fa..7fc0025 100644
--- a/src/jrummikub/ai/fdsolver/constraint/SameConstraint.java
+++ b/src/jrummikub/ai/fdsolver/constraint/SameConstraint.java
@@ -2,6 +2,7 @@ package jrummikub.ai.fdsolver.constraint;
import java.util.Arrays;
import java.util.Collection;
+import java.util.Collections;
import java.util.HashSet;
import java.util.Iterator;
@@ -56,9 +57,7 @@ public class SameConstraint<T> extends Constraint {
@Override
public Satisfiability getSatisfiability() {
- HashSet<T> range = new HashSet<T>(x.getRange());
- range.retainAll(y.getRange());
- if (range.isEmpty()) {
+ if (Collections.disjoint(x.getRange(), y.getRange())) {
return Satisfiability.UNSAT;
} else if (x.getRange().size() == 1 && y.getRange().size() == 1) {
return Satisfiability.TAUT;