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September 2017 Update

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Ingy döt Net 2017-09-23 10:01:46 +02:00
parent bba7bfd280
commit ba8067c3b7
14570 changed files with 153136 additions and 63871 deletions
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26
Task/Topswops/Haskell/topswops-2.hs
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@ -1,11 +1,21 @@
import Data.List
import Control.Arrow
import Control.Monad
import Data.List (permutations, inits)
derangements = filter (and . zipWith (/=) [1..] ). permutations
topswop = ((uncurry (++). first reverse).). splitAt
topswopIter = takeWhile((/=1).head). iterate (topswop =<< head)
swops = map (length. topswopIter). derangements
import Control.Arrow (first)
derangements :: [Int] -> [[Int]]
derangements = (filter . (and .) . zipWith (/=)) <*> permutations
topswop :: Int -> [a] -> [a]
topswop = ((uncurry (++) . first reverse) .) . splitAt
topswopIter :: [Int] -> [[Int]]
topswopIter = takeWhile ((/= 1) . head) . iterate (topswop =<< head)
swops :: [Int] -> [Int]
swops = fmap (length . topswopIter) . derangements
topSwops :: [Int] -> [(Int, Int)]
topSwops = zip [1..]. map (maximum. (0:). swops). tail. inits
topSwops = zip [1 ..] . fmap (maximum . (0 :) . swops) . tail . inits
main :: IO ()
main = mapM_ print $ take 10 $ topSwops [1 ..]