public class Tree {

private Node root;

private class Node { private int value;

private Node leftChild;

private Node rightChild;

protected Node(int value) {

this.value = value;

leftChild = null;

rightChild = null;

}

}

public Tree() {

root = null;

}

}

Write a getMax() method that returns the maximum value in the tree (or 0 if the tree is empty). The method should use a recursive helper function to find and return the max.