Label v as active // Every vertex is initially unexplored for each outgoing edge, e, that is incident to v in G do if e is unexplored then Let w be the destination vertex for e if w is unexplored and not active then Label e as a discovery edge DirectedDFS (G, w) else if w is active then Label e as a back edge else Label e as a forward/cross edge Label v as explored Algorithm 12.11: A recursive description of the DirectedDFS algorithm for search- ing from a vertex. v.