JAVA : Recursively complete the removeBelowDepth method using one helper function for a binary tree.

public class MyIntSET {

private Node root;

private static class Node {

public final int key;

public Node left, right;

public Node(int key) { this.key = key; }

}

// remove all subtrees below depth k from the original tree

public void removeBelowDepth(int k) {

// TODO

}