src/SimpleStrat.hs

   1 {-
   2  - beginner:     ~ 60%
   3  - intermediate: ~ 30%
   4  - expert:       ~  0.7%
   5  -}
   6 module SimpleStrat (simpleStrat) where
   7
   8 import Mine
   9 import System.Random
  10 import Data.Array
  11 import Control.Monad
  12
  13 simpleStrat :: Strategy
  14 simpleStrat = defaultStrategy {
  15     sName        = "SimpleStrat",
  16     sAuthor      = "Bertram Felgenhauer <int-e@gmx.de>",
  17     sDescription =
  18         "This strategy makes inferences from exposed cells and their immediate \
  19         \neighbourhood, and picks a random cell if no inference can be made.\n\
  20         \It should be equivalent to the PGMS Single Point Strategy.",
  21     sRun  = \s -> getConfig >>= flip worker s
  22 }
  23
  24 worker :: Config -> StdGen -> StrategyM String
  25 worker cfg gen = do
  26     view <- getView
  27     let actions = scan cfg view
  28     if null actions then randomMove cfg view gen >>= worker cfg
  29                     else sequence_ actions >> worker cfg gen
  30
  31 randomMove :: Config -> View -> StdGen -> StrategyM StdGen
  32 randomMove cfg@Config { cSize = Pos sX sY } view gen = let
  33     (x, gen') = randomR (1, sX) gen
  34     (y, gen'') = randomR (1, sY) gen'
  35     p = Pos x y
  36   in
  37     if view ! p == Hidden then move p >> return gen''
  38                           else randomMove cfg view gen''
  39
  40 scan :: Config -> View -> [StrategyM ()]
  41 scan cfg view = concat
  42     [ moves
  43     | (p, Exposed num) <- assocs view,
  44       let ns = neighbours cfg p
  45           ms = [n | n <- ns, view ! n == Marked]
  46           us = [n | n <- ns, view ! n == Hidden]
  47           moves | num == length ms             = [move_ n | n <- us]
  48                 | num == length ms + length us = [mark  n | n <- us]
  49                 | otherwise                    = []]