This is a collection of exercices I've done from Codewars.com.
List of exercices started but not yet finished, and what's wrong with them. (problems not listed here work as intended)
(6k) Pile of Cubes: Requires some cool algorithm for summing cubes or something. Algorithm I used for the ruby version isn't fast enough in Haskell.
(4k) Bird-mountain - The River: Mistake in how the mountain flooding was implemented. Will fix at some point.
(4k) Count squares in a chess board: Problem is solved but solution runs too slow to meet performance requirements.