import Data.Char (toLower)

compare_xos :: String -> Bool
compare_xos = same . foldl kevin (0, 0)
  where
    kevin (x, o) c
      | toLower c == 'x' = (x + 1, o)
      | toLower c == 'o' = (x, o + 1)
      | otherwise        = (x, o)
    same (x, o) = x == o