module paard

import StdEnv, StdFunc

bord :: {{Char}}
bord =
	{{'e', 'p', 's'}
	,{'o', ' ', 't'}
	,{'s', 'r', 'a'}
	}

inbord :: Int Int -> Bool
inbord x y = x >= 0 && y >= 0 && x < size bord && y < size bord.[0]

zetten :: [(Int, Int)]
zetten =
	let m = [(1,2), (-1,2), (1,-2), (-1,-2)]
	in m ++ map (\(x,y)->(y,x)) m

zet :: [(Int, Int)] -> [[(Int, Int)]]
zet [] = []
zet gehad=:[(x, y):_] =
	[ [(x+dx, y+dy):gehad]
	\\(dx,dy)<-zetten
	|  inbord (dx+x) (dy+y)
	&& not (isMember (dx+x,dy+y) gehad)
	]

str :: [(Int, Int)] -> String
str s = {bord.[x].[y]\\(x, y)<-reverse s} +++ "\n"

startposities :: [[(Int,Int)]]
startposities = [[(x,y)]\\x<-[0..2],y<-[0..2]]


($) infixr 0
($) :== id 

Start = map str $ iter ((size bord*size bord.[0]) - 2) (flatten o map zet) startposities