def test_is_connected(self): v = Vertex('v') w = Vertex('w') e1 = Arc(v, w) e2 = Arc(w,v) dg = DirectedGraph([v, w], [e1,e2]) self.assertEqual(dg.is_strongly_connected(),True) dg.remove_edge(w,v) self.assertEqual(dg.is_strongly_connected(),False)
def test_complete(self): """a two-vertex complete graph is strongly connected.""" v = Vertex('v') w = Vertex('w') dg = DirectedGraph([v,w]) dg.add_all_edges() self.assertTrue(dg.is_strongly_connected())