Reverse Binary Tree

EasyPython

Problem

Reverse a binary tree in O(n) time.

Represent each node as [value, left, right], where left and right are child nodes or None. Implement reverse_binary_tree(root) to mirror the tree in place and return root. The solution must visit each node once.

Input and Output

root is a nested node structure or None. Return the same structure after swapping the left and right subtrees of every node.

Constraints

0 <= n <= 10^5, where n is the number of nodes
Each node is represented as [value, left, right]
Node values are integers
The input is a valid binary tree

Function Signature

def reverse_binary_tree(root):

CodePython 3

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