[(0 ** []), (1 ** [3]), (5 ** [3, 4, 5, 6, 7])]
[(0 ** ([], 3)), (1 ** ([3], 4)), (2 ** ([3, 4], 5))]
[(1 ** [2]), (2 ** [6, 2]), (4 ** [120, 24, 6, 2])]
[[2, 3, 4], [3, 4], [4], []]
[(1 ** [3]), (3 ** [60, 12, 3])]
['a', 'd', 'c', 'b']
[[1, 2, 3, 4], [5, 6, 7, 8]]
[[1, 5], [2, 6], [3, 7], [4, 8]]
[]
[0, 1, 2]