RosettaCodeData/Task/Hamming-numbers/Haskell/hamming-numbers-2.hs
2023-07-01 13:44:08 -04:00

14 lines
427 B
Haskell

hammings :: () -> [Integer]
hammings() = 1 : foldr u [] [2,3,5] where
u n s = -- fix (merge s . map (n*) . (1:))
r where
r = merge s (map (n*) (1:r))
merge [] b = b
merge a@(x:xs) b@(y:ys) | x < y = x : merge xs b
| otherwise = y : merge a ys
main :: IO ()
main = do
print $ take 20 (hammings ())
print $ (hammings ()) !! 1690
print $ (hammings ()) !! (1000000-1)