Python 3

my lists(L) input: list L of non-negative integers. output: a list of lists: for every element x in L create a list containing 1,2,...,x. example: given [1,2,4] return [[1],[1,2],[1,2,3,4]]. example: given [0] return [[]].

>>> my_lists([1,2,4]) [[1], [1, 2], [1, 2, 3, 4]]

>>> my_lists([0,3]) [[]]