9. Given a directed graph G (V, E), where each vertex has a distinct integer label. For each vertex v, define R(v) to be the set of all vertices w EV for which there is a directed path from u to w in G. Furthermore, for each vertex u V, define MinLabel(e) to be the vertex with the minimum label in the set R(v). Provide an algorithm, running in 0(IVI + IEI) time, that computes MinLabel(e) for all vertices u V