-- | encode characters into numbers
encChar :: Char -> Integer
encChar c
  | '0' <= c && c <= '9' = fromIntegral $ ord c - ord '0'
encChar :: Char -> Integer
encChar c
  | '0' <= c && c <= '9' = fromIntegral $ ord c - ord '0'
encChar c
  | '0' <= c && c <= '9' = fromIntegral $ ord c - ord '0'