Writing monadic and tail-recursive code
Prerequisite
You have installed `stack`,
and pulled from Gitlab to get the latest version of the exercises.
Task
1. Open a command-line window and navigate to `CS3016-1819/Exercise02`.
2. Enter `stack test`.
3. The tests fail. Read the test outcomes carefully.
4. Change the Haskell comment on the first line of `src/Ex02.hs` to refer to your own username and name.
5. Your task is to edit `src/Ex02.hs` to modify it so all tests succeed. You should read all of this file carefully before you start work.
6. To submit, simply upload **only** your revised `Ex02.hs` file to Blackboard.
