Find Height of a Tree

/**

 * Find Height of a Tree

 *

 * @author:http://javainterviewprograms.blogspot.in/

 *

 */

public class Height_Of_The_Tree {

          public static void main(String[] args) {

                   // Binary search tree

                   Binary_Tree tree = new Binary_Tree();

                   tree.addNode(50);

                   tree.addNode(40);

                   tree.addNode(60);

                   tree.addNode(30);

                   tree.addNode(45);

                   tree.addNode(55);

                   tree.addNode(54);

                   tree.addNode(20);

                   tree.addNode(10);

                   // root.PreOrderTraversal();

                   int height = HeightOfTree(tree.getRoot());

                   System.out.println("Height Of Tree:" + height);

                   // Level Order Traversal Without Stack

                   LevelOrderTraversal(tree.getRoot(), height);

          }

          public static void LevelOrderTraversal(BSTNode root, int height) 
        {

                   for (int i = 1; i <= height; i++) {

                             LevelOrderTraversalUtil(root, i, 1);

                             System.out.println();

                   }

          }

          private static void LevelOrderTraversalUtil(BSTNode root, int level, int i) 
       {

                   if (root == null)

                             return;

                   if (i == level) {

                             System.out.print(root.data + " ");

                             // System.out.print(" data:"+root.data +" "+" level:"+level);

                   }

                   i++;

                   LevelOrderTraversalUtil(root.left, level, i);

                   LevelOrderTraversalUtil(root.right, level, i);

          }

          public static int HeightOfTree(BSTNode root)
        {

                   if (root == null) {

                             return 0;

                   }

                   int letfHeight = HeightOfTree(root.left);

                   int rightHeight = HeightOfTree(root.right);

                   if (letfHeight > rightHeight)

                             return 1 + letfHeight;

                   else

                             return 1 + rightHeight;

          }

}

Output:

Height Of Tree:5

50

40 60

30 45 55

20 54

10