public void delete (E e) {
	
		if (root == null) {
			return;
		}
		else if (root.isLeaf) {
			if (e.compareTo(root.ex) == 0) {
				root = null;
				size = 0;
			}
			return;
		}
		else {
			if (root.left.color == BLACK && root.right.color == BLACK) {//may need help
				root.color = RED;
			}
			root = deleteAt(root, e);
			if (root.color == RED) {//didn't use the help
				root.color = BLACK;
			}
			return;
		}
	}