Code Room
CodingHardcod-g236
Subject Strongly connected componentsLevel Senior–Staff~35 minCommon in Algorithms & data structures interviewsIndustries Software development

Question

You are given a directed graph with n nodes labelled 0..n-1 and a list of directed edges [u, v]. A strongly connected component (SCC) is a maximal set of nodes where every node is reachable from every other node in the set. Return the number of strongly connected components. Constraints: 1 <= n <= 2000, the graph may have self-loops and parallel edges, and there may be isolated nodes.

Implement
count_scc(n: int, edges: list[list[int]]) → int
Examples
in[5,[[0,1],[1,2],[2,0],[1,3],[3,4]]]out3
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.

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.