Leetcode 545. Boundary of Binary Tree
Return the boundary of a binary tree: list nodes on the left boundary top-down (excluding leaves), then all leaves left-to-right, then the right boundary bottom-up (excluding leaves), avoiding duplicates. The challenge is to traverse and partition nodes correctly (including edge cases like single-node or skewed trees) while preserving the required order.
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Amazon
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Early October, 2025
Amazon
Mid-level
Mid September, 2025
Meta
Senior
Slight variation where leaves of the binary tree are not included.
Early July, 2025
Meta
Senior
Sum Root to Leaf Numbers for Binary Tree
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