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From: Vir Campestris <vir.campestris@invalid.invalid>
Newsgroups: comp.lang.c++
Subject: Re: OT: Re: Sieve of Erastosthenes optimized to the max
Date: Mon, 19 Aug 2024 21:23:22 +0100
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On 16/08/2024 18:35, Bonita Montero wrote:
<snip>
> But basically I don't think it is a good idea to skip numbers exept
> multiples of two. With the three you save a sixth of memory, with
> the five you save a 15-th and at the end you get about 20% less
> storage (1 / (2 * 3) + 1 / (2 * 3 * 5) + 1 / (2 * 3 * 5 * 7) ...)
> for a lot of computation. That's the point where I dropped this
> idea and I think this extra computation is higher than the time
> for the saved memory loads.
> 
It's not just storage you save, it's also computation.

That program I published up-thread is almost as fast as yours - within 
10% of the elapsed time - while only using a single core. The amount of 
CPU used is much lower.

Andy