{- /*- * Copyright (c)2006 YAMAMOTO Takashi, * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ -} import System.Environment import System.IO import List import Maybe import qualified Data.Set as Set ff s [] = head $ Set.elems s ff s (y:ys) = if Set.size s == 1 then head $ Set.elems s else if Set.member y s then ff (Set.delete y s) ys else ff s ys do_opt1 npg n q [] = (reverse n, q) do_opt1 npg n q rs@(r:rs2) = if Set.member r q then do_opt1 npg n q rs2 else if Set.size q < npg then do_opt1 npg (r:n) (Set.insert r q) rs2 else let c = ff q rs2 nq = Set.delete c q in do_opt1 npg (r:n) (Set.insert r nq) rs2 do_opt npg rs = fst $ do_opt1 npg [] Set.empty rs do_opt_dbg npg rs = do_opt1 npg [] Set.empty rs main = do xs <- getContents args <- getArgs let ls = lines xs npgs::Int npgs = read $ args !! 0 pgs::[Int] pgs = map read ls mapM_ print $ do_opt npgs pgs