From: Bill Walton <bill.walton@...>
Date: 2008-07-20T22:17:59+09:00
Subject: Re: The next number that is not in an array

Hi David,

David A. Black wrote:

> So like this?
>
> irb(main):020:0> a = [2,3,4,8,12,13,15]
> => [2, 3, 4, 8, 12, 13, 15]
> irb(main):021:0> ([*a[0]..20] - a).shift
> => 5
>
> It's a cool idea,

Thanks.

> though I would find it somewhat hard to see what's
> going on at a glance than some of the others.

Yeah.  I wasn't sure of the overall context.  If the reserved numbers list
was static and there was a need to call the get_next method more than once,
I thought getting and saving the array difference (as a separate step before
the shift) could pay dividends later that might make it a reasonable choice.

> > Second question has to do with comments Robert Dober made like '10 times
> > slower' and '50 times faster'.  I'm assuming there's some benchmarking
> > capability I need to learn more about.  Could somebody point me?  Also,
is
> > this capability available in IRB?
>
> Have you used the Benchmark module? It's the usual tool for getting
> comparisons of different snippets that do the same thing as each
> other.

I haven't used it, but will definitely check it out.  Thanks for the
pointer.

Best regards.
Bill