naldoco

{-https://github.com/haskell-esp/ejercicios-beginning-haskell

##### 2-6. MORE MATCHES AND GUARDS

Up to this point we have introduced matching on lists and
tuples, and guards. The following tasks will help you
ensure that you have understood those concepts.

1) Define the famous Ackermann function. Try using guard.

naldoco

{-https://github.com/haskell-esp/ejercicios-beginning-haskell

##### 2-5. THE PERFECT MATCH FOR YOUR TIME MACHINES

1) For statistical purposes, write a function that
   returns the number of clients of each gender.

   * You may need to define an auxiliary data type to hold the results of this function.

naldoco

-- check   "hola"    "---a"    'b'  =  (False, "---a")
check   :: String -> String -> Char -> (Bool,String)
check word display c =
  (c `elem` word, [if x == c
                   then c
                   else y | (x, y) <- zip word display])

mkguess :: String -> String -> Int -> IO ()
mkguess word display n =
  do putStrLn (display ++ "  " ++ take n (repeat '*'))