Create a binary tree ADT that includes generic traversal methods that take a visitor, as described in Section 5.2. Write functions count and BSTcheck of Section 5.2 as visitors to be used with the generic traversal method.

boolean checkBST (BSTNode root, Integer low, Integer high) { } if (root == null) return true; // Empty subtree Integer rootkey = root. key (); if ((rootkey < low) || (rootkey > high)) return false; // Out of range. if (!checkBST (root. left (), low, rootkey)) return false; // Left side failed return checkBST (root. right (), rootkey, high);