I’m working on a project where I need to implement different types of tree traversals (in-order, pre-order, post-order) for a binary tree. I understand the basic structure of a binary tree, but I’m struggling with how to write the recursive functions for each traversal method.

Here’s the basic structure of my binary tree:

class Node:
    def __init__(self, key):
        self.left = None
        self.right = None
        self.val = key

root = Node(1)
root.left = Node(2)
root.right = Node(3)
root.left.left = Node(4)
root.left.right = Node(5)

I’ve looked at some online resources, but I’m still confused about how the recursive calls work and how they ensure the correct order.