Re: Beating C++ std::gcd

[hermann@stamm-wilbrandt.de]

Interesting.

I did let it run and stopped execution after output of the a(37) 
coordinate line after 6.5h runtime on AMD 9950X CPU.

I did want to look at it, and recently gemini did good jobs for me for 
similar tasks with python scripts and matplotlib.

This time I asked for HTML page with JavaScript and SVG:
https://share.gemini.google/HWG4yAgIxW74

Impressive what beautiful result a 544 character prompt instruction plus 
the computed log data returned:
https://stamm-wilbrandt.de/A295344.gp.html

Now it is a pleasure to step through the different circle radius 
solutions, there is a movie mode as well.

Regards,

Hermann.

On 2026-08-09 05:48, Ruud H.G. van Tol wrote:
> On 2026-08-08 13:51, Ruud H.G. van Tol wrote:
> > In a project I'm working on, I measured that about 25% of its runtime 
> > was spent in gcd.
> > The program runs with 10 threads, on a MacBook M1 Max.
> >
> > On my clang, std::gcd came out as the best suited implementation.
> > Then I started looking for more speed, and tried a lookup table for 
> > smaller values.
> > And that made it 20% faster!
> >   gcd(a, b); 0 <= a <= 511; 0 <= b <= 1023.
>
> It is used in this project:
>
> https://oeis.org/A295344/a295344.gp.txt (GP code)
> https://oeis.org/A295344/a295344_1.cpp.txt (C++ code)
> https://oeis.org/A295344/a295344_7.txt (example of output)
>
> -- Ruud