Code RoomSum root to leaf numbers
MediumPrep Room Coding #1328

Sum root to leaf numbers

CodingAlgorithms & data structuresEntry–Mid~15 min

Given a binary tree as a level-order array (null for missing) where every node value is a digit 0-9, each root-to-leaf path spells a number formed by concatenating the digits from root to leaf. Return the sum of all such numbers. If the tree is empty, return 0.

Implement
sum_root_to_leaf(level: list) → int
Examples
in[[1,2,3]]out25
What 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
InputExpectedGot
[[1,2,3]]25not run yetsample