[(1, 2), (1, 3), (2, 4), (2, 5), (3, 4), (3, 5), (4, 5)]
[(1, 2), (1, 3), (1, 4), (2, 6), (2, 7), (3, 6), (3, 7), (4, 5), (6, 7)]
[(1, 2), (1, 3), (1, 4), (2, 5), (2, 6), (3, 5), (3, 6), (5, 6)]
[(1, 2), (1, 3), (2, 3), (2, 4), (3, 5), (4, 6), (4, 7), (5, 6), (5, 7), (6, 7)]
[(1, 2), (1, 3), (2, 6), (2, 7), (3, 4), (3, 5), (4, 5), (4, 6), (5, 7), (6, 7)]
[(1, 2), (1, 3), (2, 4), (2, 5), (3, 5), (3, 6), (4, 6), (4, 7), (5, 7), (6, 7)]
[(1, 3), (1, 4), (2, 3), (2, 5), (2, 7), (3, 6), (4, 5), (4, 7), (5, 6), (6, 7)]
