module Main where

import System.IO
import System.Directory
import System.FilePath
import Control.Monad

fsize :: FilePath -> IO Integer
fsize path = withFile path ReadMode hFileSize

strFile :: (FilePath, IO Integer) -> IO [String]
strFile file = do
    let file_path = fst file
    file_size <- snd file
    return [show file_path ++ " " ++ show file_size]

listFiles :: FilePath -> IO [String]
listFiles path = do
    t <- getDirectoryContents path
    let dir = filter(`notElem` [".", ".."]) t
    files <- mapM (\f -> process path f) dir
    return $ concat files


process :: FilePath -> FilePath -> IO [String]
process path f = do
    let full_path = path </> f
    is_dir <- doesDirectoryExist full_path
    if is_dir
        then listFiles full_path
        else strFile (full_path, fsize full_path)

diff :: [String] -> String -> [String] -> String -> [String]
diff f1content f1name f2content f2name = do
    let another_dir = map (\f -> myTrim f f2name) f2content
    [f1 | f1 <- f1content, not $ myTrim f1 f1name `elem` another_dir]
    where
        myTrim s t = drop ((length t) + 4) s

main = do
    first <- getLine
    second <- getLine

    f_files <- process "." first
    s_files <- process "." second

    putStrLn ""
    putStrLn $ "Unique files from " ++ first
    mapM_ putStrLn $ diff f_files first s_files second

    putStrLn ""
    putStrLn $ "Unique files from " ++ second
    mapM_ putStrLn $ diff s_files second f_files first