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OOP & classes

Classes, instances, methods, dataclasses, and object-oriented design in Python.

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OOP & classes easy

Binary Tree Inorder Traversal in Python

Define a TreeNode class and recursively print in-order traversal (left, node, right) of a binary tree.

binary-tree recursion traversal
Python 
class TreeNode:
    def __init__(self, val=0, left=None, right=None):
        self.val = val
        self.left = left
        self.right = right


def inorder_traversal(root):
    return inorder_traversal(root.left) + [root.val] + inorder_traversal(root.right) if root else []


if __name__ == "__main__":
    # Build a…
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