Maximum path sum tree
Given a binary tree as a level-order array `arr` (using `null` for missing children, so JSON null arrives as Python None), find the maximum path sum. A path is any sequence of nodes connected by parent-child edges; it need not pass through the root and must contain at least one node. Node values may be negative. The tree is non-empty. `1 <= node count <= 30000`.
Implement
max_path_sum(arr: list[int]) → intExamples
in
[[1,2,3]]out6What a strong answer looks like
State your approach and its time/space complexity out loud before you optimize. Handle the edge cases (empty input, duplicates, overflow), and say why you chose this over the brute force. Green tests are the floor, not the grade.
0:00 of about 30 min
solution.py
InputExpectedGot
[[1,2,3]]6not run yetsample