Looking for assistance with the in order iterator(using parent node) and the post order iterator (using a stack)

*public* *class* BinaryTree { //Implements a Binary Tree of Strings *private* *class* Node { *private* Node left; *private* String data; *private* Node right; *private* Node _parent_; //reference to the parent node // the parent is null for the root node *private* Node(Node L, String d, Node r, Node p) { left = L; data = d; right = r; parent = p; } } *private* Node root;

*public* BinaryTree() { //create an empty tree }

*public* BinaryTree(String d) { //create a tree with a single node }

*public* BinaryTree(BinaryTree b1, String d, BinaryTree b2) { //merge the trees b1 AND b2 with a common root with data d }

*public* class InorderIterator implements Iterator { //An iterator that returns data in the tree in an in order pattern //the implementation must use the parent pointer and must not use an //additional data structure

public InorderIterator() { } public boolean hasNext() { return true; } public String next() { } public void remove() { } //optional method not implemented }

*public* class PostorderIterator implements Iterator { //An iterator that returns data in the tree in a post order pattern //This implementation must use a stack and must not use the parent pointer //You must use Javas stack class

public PostorderIterator() { } public boolean hasNext() { } public String next() { } public void remove() { //optional method not implemented } }

*public* Iterator _inorder_() { //return a new in order iterator object } *public* Iterator _postorder_() { //return a new post order iterator object } }