From: "David A. Black" <dblack@...>
Date: 2008-07-17T08:51:26+09:00
Subject: Re: The next number that is not in an array

Hi --

On Thu, 17 Jul 2008, Tim Conner wrote:

> I want to increment the current value of a variable to the next number
> that does not appear in an array of restricted numbers.
> e.g.
> restricted_numbers = [2,3,4,5,8,10,15,29]
>
> if the variable is currently storing 11 then I want to increment it to
> 12,
> however if the variable is currently storing 1 then I want to increment
> it to 6.
>
> How is this done in ruby?

Here's a pretty terse way -- maybe too terse, and rather
side-effect-ish, but kind of interesting:

   true while restricted_numbers.include?(n+=1)

This (and I think the other versions) keeps incrementing off the end
of the array, so you'd have to add something to make that not happen.


David

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