The following exercises is a method to be added to the IntTree class from this chapter. Yo...

The following exercises is a method to be added to the IntTree class from this chapter. You may define additional private methods to implement your public method if necessary. Several problem descriptions refer to the following reference binary trees:

Write a method called isFull that returns true if a binary tree is full and false if it is not. A full binary tree is one in which every node has 0 or 2 children. For example, reference trees #1 and #2 are not full, but #3 is full. By definition, the empty tree is considered full.

Reference Tree #1

Reference Tree #2

Reference Tree #3