i1 : G = digraph {{1,2},{2,3},{4,5},{2,5}} o1 = Digraph{1 => set {2} } 2 => set {3, 5} 3 => set {} 4 => set {5} 5 => set {} o1 : Digraph
i2 : reachable(G,{2}) o2 = {5, 2, 3} o2 : List