N-Queens results on Casio calculators

[John Keith]

(08-28-2024 08:19 PM)Hlib Wrote:  ...
Just for comparison, on modern laptop PC:
t(15)~10_minutes, t(20)~40_days.

...

In my opinion, the second version of the program (complete 10-queens benchmark) is very well suited for testing modern fast calculators. It checks not only the speed of calculations, but also manipulations with a large array of data.

As you have shown, this simple algorithm is impractical for n queens where n is greater than 12 or 14. Modern algorithms such as simulated annealing and its variants, or Knuth's Algorithm X, can find solutions for n in the thousands very quickly. See many references on Wikipedia. I would suggest that one of the modern algorithms might be more suited to testing modern calculators because they do more than just moving stuff around in memory.