linked-list: Move hints to HINTS.md

Author: rbasso

exercises/linked-list/HINTS.md

@@ -0,0 +1,13 @@
+## Hints
+
+To complete this exercise, you need to create the data type `Deque`
+and implement the following functions:
+
+- `mkDeque`
+- `pop`
+- `push`
+- `unshift`
+- `shift`
+
+You will find the type signatures already in place, but it is up to you
+to define the functions.

exercises/linked-list/src/Deque.hs

@@ -1,8 +1,5 @@
 module Deque (Deque, mkDeque, pop, push, shift, unshift) where
 
--- The task is to create the data type `Deque`
--- and implement the functions below.
-
 mkDeque :: IO (Deque a)
 mkDeque = undefined