Re^9: Algorithm RFC: fast (pseudo-)random shuffle with no repetition

karl@h3002993:~/src/perl$ time ./pmute.pl
1 2 1 2 1 2 1 2 1 2 1 2 1 2 1

real    0m0,064s
user    0m0,044s
sys     0m0,005s
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Re^10: Algorithm RFC: fast (pseudo-)random shuffle with no repetition by LanX (Saint) on Sep 24, 2023 at 19:09 UTC
The 15 came from the OP, But as I said > If this doesn't convince you that try-and-error isn't a good idea, try adding even more 1s and 2s. for instance `((1)x 51, (2) x 50)` ==> `((101!) / (51!)) / (50!) = 1.99804427433e+29` Cheers Rolf _{(addicted to the Perl Programming Language :) see Wikisyntax for the Monastery}	[reply] [d/l] [select]
Re^11: Algorithm RFC: fast (pseudo-)random shuffle with no repetition by karlgoethebier (Abbot) on Sep 24, 2023 at 20:26 UTC
There is nothing I have to be convinced of. It was clear that with this method at some point end is. With ((1)x 9, (2) x 8) the red area begins on the relatively weak machine on which I tried this via IPad/SSH: 0m0,003s in the best and 0m41,493s in the worst case so far. With ((1)x 51, (2) x 50) that's completely hopeless there. With the OP's example (15), the result was actually quite acceptable - unlike ~~what he expected~~ predicted by him. ŤThe Crux of the Biscuit is the Apostropheť	[reply]