1 files changed, 1 insertions, 1 deletions
diff --git a/src/jrummikub/ai/fdsolver/constraint/IndexConstraint.java b/src/jrummikub/ai/fdsolver/constraint/IndexConstraint.java
index 999924f..9d80a37 100644
--- a/src/jrummikub/ai/fdsolver/constraint/IndexConstraint.java
+++ b/src/jrummikub/ai/fdsolver/constraint/IndexConstraint.java
@@ -13,7 +13,7 @@ import jrummikub.ai.fdsolver.Propagator;
 import jrummikub.ai.fdsolver.Satisfiability;
 import jrummikub.ai.fdsolver.Var;
 
-public class IndexConstraint<T> implements Constraint {
+public class IndexConstraint<T> extends Constraint {
 	Var<T> target;
 	Var<Integer> index;
 	List<Var<T>> list;