regress/sys/uvm/pdsim/lru.hs

   1 {-
   2 /*      $NetBSD: lru.hs,v 1.1 2006/09/30 09:00:00 yamt Exp $    */
   3
   4 /*-
   5  * Copyright (c)2005 YAMAMOTO Takashi,
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29 -}
  30
  31 import System.Environment
  32 import System.IO
  33 import List
  34 import Maybe
  35
  36 contain x xs = isJust $ find (== x) xs
  37
  38 do_lru1 npg n q qlen [] = (reverse n, q)
  39 do_lru1 npg n q qlen rs@(r:rs2) =
  40         if contain r q then
  41                 let
  42                         nq = delete r q
  43                 in
  44                 do_lru1 npg n (r:nq) qlen rs2
  45         else if qlen < npg then
  46                 do_lru1 npg (r:n) (r:q) (qlen+1) rs2
  47         else
  48                 let
  49                         nq = take (qlen-1) q
  50                 in
  51                 do_lru1 npg (r:n) (r:nq) qlen rs2
  52
  53 do_lru npg rs = fst $ do_lru1 npg [] [] 0 rs
  54
  55 main = do
  56         xs <- getContents
  57         args <- getArgs
  58         let
  59                 ls = lines xs
  60                 npgs::Int
  61                 npgs = read $ args !! 0
  62                 pgs::[Int]
  63                 pgs = map read ls
  64         mapM_ print $ do_lru npgs pgs