Objective: Given a binary tree, write an algorithm to count all the nodes in the tree.

Example:

Approach:

Do postorder traversal.

If the root is null return 0. (base case all well for the recursion)

if the root is not null then make a recursive call to the left child and right child and add the result of these with 1 ( 1 for counting the root) and return.

Code:

Output:

Number of nodes in the given binary tree: 5

__________________________________________________ Top Companies Interview Questions..-

If you find anything incorrect or you feel that there is any better approach to solve the above problem, please write comment.
__________________________________________________