def test_1(self):
g = Graph(['A', 'B', 'C', 'D', 'E', 'F'], [(0, 1, 10), (0, 2, 8),
(1, 2, 1), (1, 3, 30),
(1, 4, 6), (2, 4, 20),
(3, 4, 7), (4, 5, 15)])
print(g.floyd())
