ADD: search up to k in approxKNN

src/mhtree/MHTree.java

@@ -50,7 +50,7 @@ public class MHTree extends Algorithm implements Serializable {
         PriorityQueue<ObjectToNodeDistanceRank> queue = new PriorityQueue<>();
         queue.add(new ObjectToNodeDistanceRank(root, object));
 
-        while (!queue.isEmpty()) {
+        while (!queue.isEmpty() && operation.getAnswerCount() < operation.getK()) {
             Node currentNode = queue.poll().getNode();
 
             if (currentNode.isLeaf())