In Preorder Tree Traversal, the order of accessing node is Node -> Left Subtree -> Right Subtree.

Code

1. Recursive Approch – 1

2. Recursive Approch – 2 (Using global variable)

3. Recursive Approch – 3 (Using pass by reference)

4. Iterative Approch – 1 (Using Stack)

5. Iterative Approch – 2 (Without Stack Using Morris Traversal)

To execute Preorder tree traversal Program : https://leetcode.com/problems/binary-tree-preorder-traversal

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