+ /**
+ * Count the number of leaves in the component tree.
+ * This is the number of hurdles, if makeUnoriented has been called.
+ */
+ size_t countLeaves();
+
+ /**
+ * Number of short branches.
+ * If makeUnoriented has been called and countLeaves is >= 3
+ * then we have a super hurdle if short branches = 0.
+ */
+ size_t shortBranches();
+