Iterative Method to find Height of Binary Tree

There are two conventions to define the height of a Binary Tree 

1) Number of nodes on the longest path from the root to the deepest node. 
2) Number of edges on the longest path from the root to the deepest node.

Iterative Method to find Height of Binary Tree: https://www.geeksforgeeks.org/iterative-method-to-find-height-of-binary-tree/