Using everything you have learned so far with linear data structures and trees, implement an AVL tree. You should use an implementation of a BST as a starting point and then incorporate rotations and balancing. (hint: add a balancing factor and height instance variable to your list node class).
AVLTree() -- Creates a new AVL Tree that is empty. It needs no parameters and returns an empty AVL Tree.
insert(item) -- Adds a new item to the tree in its appropriate spot. It needs the item and returns nothing.
delete(item) -- Removes the specified item from the tree and maintains AVL tree integrity. It needs the item and returns nothing. The tree is modified.
find(item) -- Tests to see if the specified item is in the tree. It needs the item and returns a boolean value.
isEmpty() -- Tests to see whether the AVL Tree is empty. It needs no parameters and returns a boolean value.
size() -- Returns the number of items on the AVL Tree. It needs no parameters and returns an integer.
toString() -- Returns a string of the AVL Tree, and it's contents, formatted as a list of pairs, in-order, top to bottom, left to right. For example: [(null, 55), (55, 49), (55, 76), (49, 1), (49, 53), (76, 56)]
Note: To make it more simple, your tree should not incorporate duplicates.
