SCC Count (Kosaraju)

Problem

Count the strongly connected components of a directed graph with n nodes.

Run Kosaraju's algorithm: DFS to get finish order, then DFS on the reversed graph in reverse finish order. edges is a list of [u, v] pairs.

Hint

Components of the reversed graph processed in reverse finish order come out one SCC at a time.

case 1

in: [3,[[0,1],[1,2],[2,0]]]

expected: 1

case 2

in: [4,[[0,1],[1,2],[2,0],[3,0]]]

expected: 2

case 3

in: [3,[[0,1],[1,2]]]

expected: 3

case 4

in: [5,[[0,1],[1,2],[2,0],[3,4],[4,3]]]

expected: 2

case 5

in: [5,[]]

expected: 5

Starter codePython

def count_scc(n, edges):
    # Your code here
    pass

5 test cases · run your code against them in the editor