Sieve of Eratosthenes: Difference between revisions
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Not a robot (talk | contribs) (Add Draco) |
(→Tree-merging incremental sieve: no primed names please -- the highlighting is horrendous with those) |
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_U ((x:xs):t) = x : (merge xs . _U . pairs) t -- tree-shaped folding big union |
_U ((x:xs):t) = x : (merge xs . _U . pairs) t -- tree-shaped folding big union |
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pairs (xs:ys:t) = merge xs ys : pairs t |
pairs (xs:ys:t) = merge xs ys : pairs t |
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merge xs@(x: |
merge xs@(x:xt) ys@(y:yt) | x < y = x : merge xt ys |
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| y < x = y : merge xs yt |
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| otherwise = x : merge xt yt</lang> |
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Works with odds only, the simplest kind of wheel. Here's the [http://ideone.com/qpnqe test entry] on Ideone.com, and a [http://ideone.com/p0e81 comparison with more versions]. |
Works with odds only, the simplest kind of wheel. Here's the [http://ideone.com/qpnqe test entry] on Ideone.com, and a [http://ideone.com/p0e81 comparison with more versions]. |
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