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solution for 068 with generalization to all n-gon

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This commit is contained in:
Yann Esposito 2012-10-23 16:24:17 +02:00
parent e04f1c5737
commit da0350adc4
1 changed files with 20 additions and 24 deletions
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44
068.hs
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@ -29,18 +29,17 @@ import Debug.Trace
-- For testing -- For testing
gonSize = 3 -- gonSize = 3
magic = 9 -- magic = 9
-- gonSize = 5 gonSize = 5
-- magic = 16
data Choice = Choice [Int] data Choice = Choice [Int]
safeIndex s l i = if (length l<i+1) then trace ("ERROR (" ++ s ++ "): " ++ show l ++ "(" ++ show i ++ ")") l!!i else l!!i safeIndex s l i = if (length l<i+1) then trace ("ERROR (" ++ s ++ "): " ++ show l ++ "(" ++ show i ++ ")") l!!i else l!!i
instance Show Choice where instance Show Choice where
show (Choice l)= str ++ show l show (Choice l)= str
where where
n = length l n = length l
nbLines = if n<2*gonSize then (n-1) `div` 2 else gonSize nbLines = if n<2*gonSize then (n-1) `div` 2 else gonSize
@ -65,8 +64,8 @@ instance RAS Choice where
add (Choice l) e = Choice (l++[e]) add (Choice l) e = Choice (l++[e])
loop f (Choice l) = map f l loop f (Choice l) = map f l
testPartialGon :: Choice -> Bool testPartialGon :: Int -> Choice -> Bool
testPartialGon c = testPartialGon magic c =
let let
n = nbChoices c n = nbChoices c
nbLines = if n<2*gonSize then (n-1) `div` 2 else gonSize nbLines = if n<2*gonSize then (n-1) `div` 2 else gonSize
@ -82,31 +81,28 @@ testLine c val n =
in in
(==val) . sum . map (at c) $ line (==val) . sum . map (at c) $ line
allTests :: [Choice] allTests :: [(Int,Choice)]
allTests = testWith (Choice []) (Choice [1..2*gonSize]) allTests = concatMap (\s -> testWith s (Choice []) (Choice [n,n-1..1]) ) [6..3*((gonSize*2)-1)]
where
n=2*gonSize
testWith :: Choice -- choosen testWith :: Int -- Sum to verify
-> Choice -- choosen
-> Choice -- left choices -> Choice -- left choices
-> [Choice] -- successful choices -> [(Int,Choice)] -- successful choices
testWith c lc = testWith magic c lc =
if testPartialGon c if testPartialGon magic c
then if nbChoices lc == 0 then if nbChoices lc == 0
then [c] then [(magic,c)]
else concat $ loop newTest lc else concat $ loop newTest lc
else [] else []
where where
len = nbChoices c len = nbChoices c
newTest x = if len>=3 && (len `rem` 2 == 1) && x<at c 0 newTest x = if len>=3 && (len `rem` 2 == 1) && x<at c 0
then trace (show c ++ " len: " ++ show len ++ " " ++ show x ++ "<" ++ show (at c 0)) [] then []
else testWith (add c x) (remove lc x) else testWith magic (add c x) (remove lc x)
main :: IO () main :: IO ()
main = do main = do
print $ Choice [4,3,2,6,1,5] putStrLn "allTest: "
putStr "testPartialGon $ Choice [4,3,2,6,1,5]: " mapM_ print $ allTests
print $ testPartialGon $ Choice [4,3,2,6,1,5]
putStr "testPartialGon $ Choice [6,2,1,3,5,4]: "
print $ testPartialGon $ Choice [6,2,1,3,5,4]
print $ Choice [6,2,1,3,5,4]
putStr "allTest: "
print $ allTests