Finding max depth of binary tree without recursion

Question

Recursive mechanism to find max depth of depth of binary tree is very straightforward, but how can we do it efficiently without recursion as I have large tree where I would

Answer 1

If you can maintain left and right values at each node, it can be done.

http://leetcode.com/2010/04/maximum-height-of-binary-tree.html.

Possible duplicate: Retrieving a Binary-Tree node's depth non-recursively