def test_is_connected_sees_non_connected_graph(self): a, b, c, d = Vertex('a'), Vertex('b'), Vertex('c'), Vertex('d') e = Vertex('e') g = Graph([a, b, c, d, e]) g.add_edge(Edge(a, b)) g.add_edge(Edge(b, c)) g.add_edge(Edge(c, d)) g.add_edge(Edge(d, a)) self.assertFalse(g.is_connected())
def test_is_connected_sees_connected_graph(self): """a graph is connected if there is a path from every node to every other node""" a, b, c, d = Vertex('a'), Vertex('b'), Vertex('c'), Vertex('d') g = Graph([a, b, c, d]) g.add_edge(Edge(a, b)) g.add_edge(Edge(b, c)) g.add_edge(Edge(c, d)) g.add_edge(Edge(d, a)) self.assertTrue(g.is_connected())