99 Elm Problems/Problem 28

Sort a list of lists.28.a) Sort a list of list according to length of sublists28.b) Sort the elements of this list according to their length frequency; i.e., lists with rare lengths are placed first, others with a more frequent length come later.

# # # THIS IS A STUB # # #

Example in Elm:
import Html exposing (text)
import List

f : Int -> Int
-- your implementation goes here

main = text (toString (f 0))