Height of BST

	package bst;
	import static java.lang.Math.max;
	/**
	* Created by panded4
	*/
	public class HeightBST {
	int leftH = 0, rightH = 0;
	private TreeNode head;
	public HeightBST() {
	this.head = createTree();
	}
	public static void main(String[] args) {
	HeightBST heightBST = new HeightBST();
	System.out.println(heightBST.calculateHeight(heightBST.head));
	}
	private TreeNode createTree() {
	TreeNode n1 = new TreeNode(1);
	TreeNode n2 = new TreeNode(2);
	TreeNode n3 = new TreeNode(3);
	TreeNode n4 = new TreeNode(4);
	TreeNode n5 = new TreeNode(5);
	TreeNode n6 = new TreeNode(6);
	TreeNode n7 = new TreeNode(7);
	TreeNode n8 = new TreeNode(8);
	TreeNode n9 = new TreeNode(9);
	n1.left = n2;
	n1.right = n3;
	n2.left = n4;
	n2.right = n5;
	n3.left = n6;
	n3.right = n7;
	n4.left = n8;
	n4.right = n9;
	return n1;
	}
	int calculateHeight(TreeNode head) {
	if (head == null) {
	return 0;
	}
	leftH = calculateHeight(head.left);
	rightH = calculateHeight(head.right);
	return 1 + max(leftH, rightH);
	}
	}

view raw HeightBST.java hosted with ❤ by GitHub