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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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12
Task/Happy-numbers/Haskell/happy-numbers-1.hs
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@ -3,9 +3,11 @@ import Data.Set (member, insert, empty)
isHappy :: Integer -> Bool
isHappy = p empty
where p _ 1 = True
p s n | n `member` s = False
| otherwise = p (insert n s) (f n)
f = sum . map ((^2) . toInteger . digitToInt) . show
where
p _ 1 = True
p s n
| n `member` s = False
| otherwise = p (insert n s) (f n)
f = sum . (((^ 2) . toInteger . digitToInt) <$>) . show
main = mapM_ print $ take 8 $ filter isHappy [1..]
main = mapM_ print $ take 8 $ filter isHappy [1 ..]

22
Task/Happy-numbers/Haskell/happy-numbers-2.hs
View file

@ -1,10 +1,18 @@
import Data.Array
happy x = if xx <= 150 then seen!xx else happy xx where
xx = dsum x
seen :: Array Int Bool
seen = listArray (1,150) $ True:False:False:False:(map happy [5..150])
dsum n | n < 10 = n * n
| otherwise = let (q,r) = n `divMod` 10 in r*r + dsum q
happy x =
if xx <= 150
then seen ! xx
else happy xx
where
xx = dsum x
seen :: Array Int Bool
seen =
listArray (1, 150) $ True : False : False : False : (happy <$> [5 .. 150])
dsum n
| n < 10 = n * n
| otherwise =
let (q, r) = n `divMod` 10
in r * r + dsum q
main = print $ sum $ take 10000 $ filter happy [1..]
main = print $ sum $ take 10000 $ filter happy [1 ..]