Adopt user Francky's solution to Problem 44 in Haskell
Solve Problem 45 in Haskell, very slow
Add an alternative solution to Problem 45 in Haskell

Previously O(v), now O(v^(1/2))
Solve Problem 46 in Haskell
Solve Problem 47 in Haskell
Solve Problem 48 in Haskell
Factor out a takeLast function in Problem 48 Haskell
Solve Problem 49 in Haskell