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Algorithm writing tips?
#20
Stereo Wrote:Something I thought about later... sqrt is not cheap (iirc it uses Newton's method to approximate?).

primesList.get(i) <= Math.sqrt(n)
Use
primeslist.get(i)**2 <= n

Huh... not sure why I didn't think about this earlier. The sqrt method uses an iterative equation, that's for sure. One such method: sqrt(2) = 1 + 1/(2 + 1/(2 + 1/(2 + ... ))) = 1.414213...

The total operation time was reduced about 20%. Not bad.
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Messages In This Thread
Algorithm writing tips? - by KajitiSouls - 2009-01-11, 10:40 PM
Algorithm writing tips? - by Stereo - 2009-01-11, 10:58 PM
Algorithm writing tips? - by KajitiSouls - 2009-01-11, 11:36 PM
Algorithm writing tips? - by Nikkey - 2009-01-12, 09:58 AM
Algorithm writing tips? - by Stereo - 2009-01-12, 11:52 AM
Algorithm writing tips? - by KajitiSouls - 2009-01-12, 03:53 PM
Algorithm writing tips? - by Nikkey - 2009-01-12, 04:19 PM
Algorithm writing tips? - by Stereo - 2009-01-12, 04:50 PM
Algorithm writing tips? - by KajitiSouls - 2009-01-12, 05:25 PM
Algorithm writing tips? - by Nikkey - 2009-01-12, 05:59 PM
Algorithm writing tips? - by GummyBear - 2009-01-12, 08:13 PM
Algorithm writing tips? - by KajitiSouls - 2009-01-12, 10:26 PM
Algorithm writing tips? - by Nikkey - 2009-01-13, 10:28 AM
Algorithm writing tips? - by GummyBear - 2009-01-13, 11:41 PM
Algorithm writing tips? - by Stereo - 2009-01-15, 10:38 AM
Algorithm writing tips? - by Nikkey - 2009-01-15, 11:02 AM
Algorithm writing tips? - by Kiley - 2009-01-16, 02:37 AM
Algorithm writing tips? - by KajitiSouls - 2009-01-18, 01:48 AM
Algorithm writing tips? - by Stereo - 2009-01-18, 04:46 PM
Algorithm writing tips? - by KajitiSouls - 2009-01-18, 05:37 PM
Algorithm writing tips? - by Nikkey - 2009-01-18, 06:26 PM
Algorithm writing tips? - by Stereo - 2009-01-18, 08:02 PM
Algorithm writing tips? - by KajitiSouls - 2009-01-18, 08:29 PM
Algorithm writing tips? - by Stereo - 2009-01-18, 10:45 PM
Algorithm writing tips? - by Nikkey - 2009-01-19, 02:10 AM

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