http://icpc2011.ait.kyushu-u.ac.jp/icpc2011/contest/all.pdf problem G

gistfile1.hs

import Data.SBV
import Data.List.Split
import Control.Applicative
import Control.Monad
import Data.Char

(!!?) :: [SBool] -> Int -> SBool
ls !!? j
  | j < 0 = false
  | j >= length ls = false
  | otherwise = ls !! j

(!!??) :: [[SBool]] -> Int -> [SBool]
ls !!?? j
  | j < 0 = []
  | j >= length ls = []
  | otherwise = ls !! j

main :: IO ()
main = do
  t <- map read . words <$> getLine
  case t of
    [0, 0] -> do
      return ()
    [h, w] -> do
      bd <- replicateM h $ getLine
      go h w bd
      main

go :: Int -> Int -> [[Char]] -> IO ()
go h w bd = do
  let count [] = 0 :: SInteger
      count (x:xs) = (ite x 1 0) + count xs

      mine ass = do
        let dotIsNotMine =
              [ bnot a
              | j <- [0..h-1]
              , i <- [0..w-1]
              , let c = bd !! j !! i
              , let a = ass !! j !! i
              , c == '.'
              ]

            numIsCorrect =
              [ sum
                [ ite a 1 0
                | dj <- [-1 .. 1]
                , di <- [-1 .. 1]
                , let a = ass !!?? (j + dj) !!? (i + di)
                ]
                .== (literal n :: SInteger)
              | j <- [0..h-1]
              , i <- [0..w-1]
              , let c = bd !! j !! i
              , isDigit c
              , let n = read [c] :: Integer
              ]

        bAnd $ dotIsNotMine ++ numIsCorrect

  res <- minimize (Iterative True) count (h * w) (mine . chunksOf w)
  print res