Postorder Traversal in Python

Postorder traversal is a depth-first search (DFS) method where nodes are visited in the order: left subtree, right subtree, and then the root. This traversal ensures child nodes are processed before their parent, making it ideal for applications like tree deletion, expression evaluation, and directory traversal. For example, in a tree with nodes 1, 2, 3, 4, and 5, the postorder traversal sequence is: 4, 5, 2, 3, 1. It can be implemented recursively for simplicity or iteratively using stacks for advanced scenarios.

This traversal method is fundamental in tree-based algorithms and real-world applications such as generating postfix expressions, evaluating hierarchical structures, and ensuring safe tree deletion. Mastering postorder traversal equips you to handle problems where child nodes require priority processing. 

For more details, please go through - Postorder Traversal of Binary Tree