Code Room
CodingMedium
Question
An undirected graph on n nodes (0..n-1) has edges given as [u, v, w] where each weight w is either 0 or 1. Return the minimum-weight path length from s to t, or -1 if t is unreachable. You should achieve O(V + E) rather than a log factor. Constraints: 1 <= n <= 10^4; w in {0, 1}.
Implement
zero_one_bfs(n: int, edges: list[list[int]], s: int, t: int) → intExamples
in
[5,[[0,1,1],[1,2,0],[2,3,1],[3,4,0],[0,4,1],[0,3,1]],0,4]out1What 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.
Learn the concepts
Vibe coding: describe the solution in plain language (or narrate it) and the coach grades your approach. Generating runnable code from your description is coming next.
Run or narrate your approach, then ask the coach.