title: Return nth largest data value in subtree of BST
body: <p>Return the nth largest data value in the subtree rooted at this node. Imagine
  that the data values were stored in a sorted, 0-based array, with duplicate
  values allowed. The return values would be the one stored in the array at
  index n.</p>
  <p>Note that this method must run in O(h) where h = height of the tree.</p>
  <p>@return the nth data value, from a sorted list</p>
  <p>e.g. e.g. bst 7 3 5, 0th is 3, 1st is 5, 2nd is 7</p>
  <pre><code> public class Node
  
  int dataCount; // number of keys with value equal to data stored at this node
  
  int treeSize; // number of keys stored in the subtree rooted at this node int data;
  
  Node left;
  
  Node right; //Get nth largest value of of subtree from the input node. Method to run in o(height)
  
   
  
  int obtain(Node n, int n){
  
  }
  </code></pre>
  <p>Please complete the obtain method in JAVA</p>