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