Hint 2

• If the current node r is null, return false.
• If the current node r stores the targetElement, return true;.
• If the left child of the current node is not null, then invoke the algorithm recursively with parameter equal to the left child of the current node and targetElement. If the recursive call returns true, then which value must be returned by the method? Do not return if the recursive calls returns false (why)?
• Do the same thing with the right child of the current node.
• If the algorithm has not returned a value after the second call, then the method must return which value before it terminates?