How to remember in-order traversal and pre-order traversal in an easy and unforgettable way?

Binary Tree traversal such as preorder traversal, inorder traversal, postorder traversal, and level order traversal is commonly interviewed by many IT companies.

It confuses me to remember the iterative implementation of pre-order traversal and inorder traversal.

Here are the problems from leetcode.

https://leetcode.com/problems/binary-tree-inorder-traversal/

https://leetcode.com/problems/binary-tree-preorder-traversal/

https://stackoverflow.com/questions/65418500/how-to-remember-in-order-traversal-and-pre-order-traversal-in-an-easy-and-unforg December 23, 2020 at 11:04AM