Foldable Tree
Detailed guide and Python implementation for the 'Foldable Tree' problem.
Problem Statement
Write a function is_foldable(tree_arr) that takes an array representation of a binary tree tree_arr and checks if the tree is foldable. A tree is foldable if its left and right subtrees are structural mirrors of each other (value does not matter, only structure).
- •0 <= len(tree_arr) <= 1000
Examples
tree_arr = [1, 2, 3, None, 4, 5, None]
True
Left child has right child 4. Right child has left child 5. Structures are symmetric mirrors.
tree_arr = [1, 2, 3, 4, None, 5, None]
False
Need a Hint?
Edge Cases to Watch
- Empty input structures
- Single element inputs
- Large numerical bounds
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