import Char

main = guess 1 10

query ot = do putStr ot
              ans <- getLine
              if (ans == "ano") then return True else return False

guess :: Int -> Int -> IO ()
guess m n = do putStrLn ("Mysli si cele cislo od " ++ show m
		         ++ " do " ++ show n ++ ".")
	       kv m n

kv m n =
  do if m==n then putStrLn ("Je to " ++ show m ++ ".")
             else do o <- query ("Je tve cislo vetsi nez " ++ show k ++ "? ")
                     if o then kv (k+1) n else kv m k
  where k = (m+n) `div` 2