#!/usr/bin/runghc

module Recursion05Reverse where

import Data.List

-- This one is inefficient
reverseMe :: [a] -> [a]
reverseMe [] = []
reverseMe (x : xs) = reverseMe xs ++ [x]

reverseEff :: [a] -> [a] -> [a]
reverseEff [] new = new
reverseEff (x : xs) new = reverseEff xs (x : new)

reverseFoldl :: [a] -> [a]
reverseFoldl = foldl' (\acc x -> x : acc) []

reverseFlip :: [a] -> [a]
reverseFlip = foldl' (flip (:)) []

main :: IO ()
main = do
  putStrLn (reverse "evil")
  putStrLn (reverseMe "taxes")
  putStrLn (reverseEff "backwards" [])
  putStrLn (reverseFoldl "reverse")
  putStrLn (reverseFlip "park")

-- boobytrap