[UVA][SCC變形] 10510 - Cactus
Problem BCactusInput: standard inputOutput:
standard output
A directed graph is a set V of vertices and a set of E ∈
{V x V} edges. An edge (u,v) is said to be directed
from u to v (the edge (v,u) has the opposite direction). A
directed cycle in a directed graph is...
