Many graph applications look for a minimal way to connect each vertex to
every other vertex.
Examples: bridging gaps, identifying bottlenecks
A graph G = (V, E) is strongly connected if for every pair of
vertices <u,v>, u,v V, there is a path ()
from u to v (u v) and from v to u (v u).
A strongly connected component (SCC) of a graph G = (V, E) is a maximal
set U V such that for every pair <u,v> U,
u v and v u.
Define: The transpose of graph G = (V, E) is the graph