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|
{-# LANGUAGE FlexibleContexts #-}
module Main where
import Control.Lens
import Linear.V2
import Linear.V3
import Data.Matrix
--import Numeric.LinearAlgebra
import System.Random
import Foreign.Storable
data Square = X -- Attacked
| Qu -- Queen
| O -- Open/available
deriving (Show, Eq)
--board = V3 <$> [0..8] <*> [0..8] <*> [0]
--board = [(r,c,X) | r <- [0..8], c <- [0..8] ]
lo8 = [0..8] -- list of 8
initBoard = matrix 8 8 $ \_ -> O
placeQueen (r,c) b = placeQueen' $ markAttacked b
where
placeQueen' b = setElem Qu (r,c) b
markAttacked b = rowAttacked $ colAttacked $ diagAttacked b
fX = (\_ x -> X)
rowAttacked b = mapRow fX r b
colAttacked b = mapCol fX c b
diagAttacked b = let d = diag r c
attack ap ab = setElem X ap ab
attackall [x] = attack x b
attackall (x:xs) = attack x (attackall xs)
in attackall d
-- in last $ map (\p -> setElem X p b) d
-- in last $ scanr (\p -> setElem X p) b
--solve b = placeQueen (nextAvail b) b
nextAvail b = head [(x,y) | x <- [1..8], y <- [1..8], b ! (x,y) == O]
-- solve b = placeQueen n
-- where n = nextAvail b
-- next = placeQueen n
-- solve' =
-- solve b =
-- where solve' b = (\n = placeQueen $ nextAvail b)
solve b = second
where first = placeQueen (nextAvail b) b
second = placeQueen (nextAvail first) first
solve' b = s (nA b) b
where s n b = placeQueen n b
nA b = nextAvail b
--diag r c = [(x,y) | x <- [1..8], y <- [1..8], (abs x-y) == 1 ]
diag r c = let rl = [1..r]
rr = [r..8]
cu = [1..c]
cd = [c..8]
in zip rl cu ++ zip rr cd ++
zip (reverse rl) cd ++ zip (reverse rr) cu
allops a b = [(a, a), (a, b), (b, a), (b, b)]
ops = allops (+1) (subtract 1)
applyop (x,y) (a,b) = (a x,b y)
applyops p = map (applyop p) ops
mapDiag f c b = map (\(x,y) -> setElem f (x,y) b) ds
where ds = diag'' c
mapDiag' f c b = map (on b f) ds
where ds = diag'' c
on b x p = let next bo = set x p bo
in map (next) b
set x p b = setElem x p b
--mapDiag'' f c b = take 10 $ iterate (map (set f) ds) b
-- mapDiag'' f c b = take 10 $ iterate (
-- where ds = diag'' c
-- eachD' p = setElem f p
-- eachD [p] = eachD' p
-- eachD (p:ps) = eachD' p : eachD ps
markX p b = setElem X p b
mapDiag''' f p b = applyfs fs b
where ds = diag'' p
fs = map (\x y -> markX x y) ds
applyfs [x] b = x b
applyfs (x:xs) b = applyfs x (applyfs xs)
onBoard b f = let next n = f n
in next b
--eB = mapDiag''' (\_ -> 1) (5,5) $ matrix 8 8 (\_ -> 0)
diag'' c = apply c
where
min = 1
max = 8
ops a b = [(a, a), (a, b), (b, a), (b, b)]
allops = ops (+1) (subtract 1)
applyop (x,y) (a,b) = (a x,b y)
applyopr (a,b) (x,y) = traverse' (\(d,f) -> (a d, b f)) (x,y)
traverse' f x = takeWhile (within) $ iterate f x
within (x,y) = let within' z = z >= min && z <= max
in within' x && within' y
applyops ops p = map (\x -> applyopr x p) ops
apply x = concat $ applyops allops x
-- opfs ops = map (\(o1,o2) -> (\(x,y) -> (o1 x, o2 y))) ops
-- applyops x = map x opfs
-- ops = map (
--applyops (x,y) = map (($ x), ($ y)) $ allops (+1) (-1)
-- fx a b = map \((oa,ob) -> ((cx,cy) -> (oa cx, ob cy))) $ allops (+1) (-1)
--applyops x = [(((fst f) (fst x)), ((snd f) (snd x))) | f <- allops (+1) (-1)]
-- applyops x = (fst x, snd x)
-- applyops x = map \((p,m) -> (p (fst x), m (snd x))) $ allops (+1) (-1)
-- apply c = map (\(p,m) -> (p (fst c), m (snd c))) $ allops (+1) (-1)
-- apply ops c = [( (fst o) (fst c), (snd o) (snd c) | o <- ops
-- diag (r,c) b =
-- where l = (r-1,c-1)
-- r = (r+1,c+1)
-- lowbound = 1
-- highbound = 8
--initBoard = (8><8) $ repeat O
--firstOpen b = take 1 [(r,c)| r <- [1..8], c <- [1..8], b ! (r,c) == O]
-- firstOpen b = let
-- elem x y = b ! (x, y)
-- in map
-- nextOpen b =
-- solve = let board = initBoard
--avail r c b =
--rowOccupied r b = any (== Q) $ getRow r b
-- diags p = let r = r p
-- l = l p
-- in p : inRange r
-- where inRange x = x >= 1 && x <= 8
-- inRange' (x,y) = inRange (x) && inRange (y)
-- r x = (fst x + 1, snd x + 1)
-- l x = (fst x - 1, snd x - 1)
-- nexts x = diags' x
-- diags' x = [(fst x - 1, snd x -1), (fst x + 1, snd x + 1)]
-- -- down x = (fst x - 1, snd x - 1)
-- -- down (r,c) = let d = (r-1,c-1) in if inRange d then d : down d else
-- -- up (r,c) = let u = (r+1,c+1) in u : up u
--mapDiag r c = undefined
--placeAll = repeat 8 placeQueen
winnable = undefined
nextOpen board = undefined
-- placeQueen r c =
--b = getE
--placeQueen r c b = b ^.
-- rand = do
-- g <- newStdGen
-- print $ take 8 $ (randomRs (0, 8) g)
-- try r c = let next b = placeQueen r c b
-- in next initBoard
-- try' p = let next b = p b
-- in next initBoard
--res = [ try x y | x <- lo8, y <- lo8 ]
main :: IO ()
main = do
putStrLn "Hi"
|
