Yes, bucket sort is simpler and O(n) too. But your examples are too simple: think ((0, val0), (1, val1), ..., (n, valn)) and ((0, val0_1), (0, val0_2), (0, val0

Yes, bucket sort is simpler and O(n) too. But your examples are too simple: think ((0, val0), (1, val1), ..., (n, valn)) and ((0, val0_1), (0, val0_2), (0, val0_3), (1, val1_1), ..., (k, valk_6)) or somesuch.