Talk:Hailstone sequence: Difference between revisions
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(A better Haskell version.) |
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<br>No mention was given to explain the reason of the deletion of those two examples. -- [[User:Gerard Schildberger|Gerard Schildberger]] ([[User talk:Gerard Schildberger|talk]]) 20:43, 5 November 2013 (UTC) |
<br>No mention was given to explain the reason of the deletion of those two examples. -- [[User:Gerard Schildberger|Gerard Schildberger]] ([[User talk:Gerard Schildberger|talk]]) 20:43, 5 November 2013 (UTC) |
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==Haskell== |
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The Haskell version is 18 lines long. This version is 12 lines long and prints all of the chain for n = 27: |
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import Data.List |
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import Data.Ord(comparing) |
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main = do putStrLn $ "Collatz sequence for 27: " ++ ((show.hailstone) 27) ++ "\n" |
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putStrLn $ "The number " ++ (show longestChain) |
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++" has the longest hailstone sequence for any number less then 100000." |
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hailstone n |
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| n == 1 = [1] |
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| even n = n:(hailstone (n `div` 2)) |
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| otherwise = n:(hailstone (3*n+1)) |
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longestChain = fst $ maximumBy (comparing snd) $ map ((\x -> (x,(length.hailstone) x))) [1..100000] |
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Should this be used instead? [[User:Mathlover2|Mathlover2]] ([[User talk:Mathlover2|talk]]) 16:31, 24 February 2015 (UTC) |
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