Pre Order Traversal in Python

Preorder traversal is a depth-first search (DFS) method where nodes of a binary tree are visited in the order: root, left subtree, and right subtree. Starting at the root, you recursively traverse the left subtree and then the right subtree. For example, in the tree with nodes 1, 2, 3, 4, and 5, the preorder traversal sequence is: 1, 2, 4, 5, 3. This traversal is ideal for applications where the root must be processed first, such as copying a tree, serializing and deserializing binary trees, and evaluating expression trees. It can be implemented recursively or iteratively using a stack.

Preorder traversal is a fundamental technique for working with binary trees and solving problems involving hierarchical data. It differs from other methods like inorder and postorder traversal by prioritizing the root before subtrees. Whether you're working on tree algorithms, evaluating expressions, or handling hierarchical structures, mastering preorder traversal is essential for efficient problem-solving. 

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