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Reverse a Binary Tree
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Reverse a Binary Tree

EasyPython

Problem

Reverse a binary tree using any language. Represent the tree as nested lists in the form [value, left, right], where an empty child is null; return the same representation after swapping every node's children. Implement def invert_binary_tree(root):, preserving node values and returning null for an empty tree.

Examples: [4, [2, null, null], [7, null, null]] becomes [4, [7, null, null], [2, null, null]]; null remains null. The tree contains at most 500 nodes.

Constraints

  • The tree is represented as [value, left, right].
  • Each child is either null or another nested tree.
  • 0 <= number of nodes <= 500
  • Node values are integers.
  • The transformation must preserve every node value.

Function Signature

def invert_binary_tree(root):
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