uedamac:tmp ueda$ cat q1.hs
   main = getContents >>= putStrLn. unwords . f . words
   f [] = []
   f (a:b:c) = [b,a] ++ f c
   uedamac:tmp ueda$ echo {1..10} | ./q1
   2 1 4 3 6 5 8 7 10 9

uedamac:tmp ueda$ cat q2.hs
   main = getContents >>= print . g. (Count 0 0 0 0)
   data Count = Count Int Int Int Int String deriving Show
   g (Count a b c d []) = Count a b c d []
   g (Count a b c d ('ユ':'ニ':'ケ':'ー':'ジ':str)) = g (Count (a+1) b c d str)
   g (Count a b c d ('ユ':'ニ':'ゲ':'ー':'ジ':str)) = g (Count a (b+1) c d str)
   g (Count a b c d ('U':'S':'P':str)) = g (Count a b (c+1) d str)
   g (Count a b c d ('U':'P':'S':str)) = g (Count a b c (d+1) str)
   g (Count a b c d (_:str)) = g (Count a b c d str)
   uedamac:tmp ueda$ echo ユニゲージユニケージユニゲージUSP友の会USP友の会UPS友の会UPS友の会 | ./q2
   Count 1 2 2 2 ""

uedamac:tmp ueda$ cat q3.hs
   main = do a <- readFile "file1"
    b <- readFile "file2"
    c <- readFile "file3"
    d <- readFile "file4"
    g [("file1",a),("file2",b),("file3",c),("file4",d)]
   
   g [] = return ()
   g (a:ds) = f a ds >> g ds
   f a ds = putStrLn $ concat $ map (h a) ds
   h (f1,a) (f2,b) = if a == b then unwords [f1,f2] else []
   uedamac:tmp ueda$ ./q3
   file1 file3
   
   
   

uedamac:tmp ueda$ cat q4.hs
   main = getContents >>= print . f. map (\\x -> read x :: Int) . words
   
   f ns = odd ++ eve
    where odd = filter (\\x -> x `mod` 2 == 0) ns
    eve = filter (\\x -> x `mod` 2 == 1) ns
   uedamac:tmp ueda$ echo 3 8 2 10 1 8 9 | ./q4
   [8,2,10,8,3,1,9]

uedamac:tmp ueda$ cat q5.hs 
   main = getContents >>= putStrLn . unwords . f . filter (\\x -> x == '0' || x == '1')
   f (a:ss) = f' (a:ss) a
   f' [] _ = []
   f' str a = (a:lng) : f' (dropWhile (== a) str) c
    where b = length $ takeWhile (== a) str
    c = if a == '0' then '1' else '0'
    lng = if b == 1 then "" else show b
   
   uedamac:tmp ueda$ echo 000001111111111001010 | ./q5 
   05 110 02 1 0 1 0

uedamac:tmp ueda$ cat q6.hs
   import Data.List.Split
   main = getContents >>= putStrLn . unwords . g . splitWhen (== -1). f . map (\\x -> read x :: Int) . words
   
   f (a:b:[]) = if a+1 == b then [a,b] else [a,-1,b]
   f (a:b:ns) = if a+1 == b then a : f (b:ns) else [a,-1] ++ f (b:ns)
   
   g [] = []
   g (a:as) = h a : g as
   
   h as = if a == b then a else a ++ "-" ++ b
    where a = show $ head as
    b = show $ last as
   uedamac:tmp ueda$ echo 1 2 3 5 6 8 10 11 12 15 | ./q6
   1-3 5-6 8 10-12 15

uedamac:tmp ueda$ cat q7.hs
   import Data.Digest.Pure.MD5
   import qualified Data.ByteString.Lazy.Char8 as B
   main = g $ f [000..999]
   
   g [] = return ()
   g ((n,a):as) = (if t `B.isPrefixOf` aa then print n else return () ) >> g as
    where t = B.pack "250"
    aa = B.pack $ show a
   
   f [] = []
   f (n:ns) 
    | n < 10 = (n,(md5 $ B.pack ("00" ++ (show n)))) : f ns
    | n < 100 = (n,(md5 $ B.pack ("0" ++ (show n)))) : f ns
    | otherwise = (n,(md5 $ B.pack (show n))) : f ns
   uedamac:tmp ueda$ ./q7 
   456

uedamac:tmp ueda$ cat q8.hs
   main = getContents >>= putStrLn . unlines . f. f. f . lines 
   
   f [] = [] 
   f (a:[]) = [] 
   f (a:b:lns) 
    | last a == head b = (a ++ "->" ++ b) : f lns
    | otherwise = f lns
   uedamac:tmp ueda$ gsort -R /usr/share/dict/words | ./q8
   rhombogenic->cattiness->sarkar->rhamnaceous->swishing->geneticism->ministryship->pleonastical