exercise 10

[flip111]

In exercise 10 it's not clear that you need the previous function (from exercise 9) this is not really user friendly. Also imports do not work so you can not use the native pack or group functions from Data.List

pack (x:xs) = let (first,rest) = span (==x) xs
               in (x:first) : pack rest
pack [] = []

encode :: Eq a => [a] -> [(Int, a)]
encode xs = (enc . pack) xs
    where enc = foldr (\x acc -> (length x, head x) : acc) []