Range sum in BST
Given a binary search tree as a level-order list (None marks a missing child; children of None are omitted) and an inclusive value range [lo, hi], return the sum of values of all nodes with value in [lo, hi]. Exploit the BST property to prune subtrees that cannot contain in-range values. An empty tree sums to 0.
Implement
bst_range_sum(level: list, lo: int, hi: int) → intExamples
in
[[10,5,15,3,7,null,18],7,15]out32What 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 15 min
solution.py
InputExpectedGot
[[10,5,15,3,7,null,18],7,15]32not run yetsample