[kw-pm] UNS: picking a random list element, the hard way

[Abram Hindle]

We golfed about this problem a while back.

See the first challenge:

http://kw.pm.org/wiki/index.cgi?GolfChallenge

abram

On 02/25/2011 10:52 AM, Robert P. J. Day wrote:
> 
>   for your entertainment value, here's an optional exercise i'm going
> to give out in next week's perl class.  it's not so much a perl
> question as it is an algorithmic analysis question that's actually
> quite simple to code once you figure it out.
> 
>   JOB: pick a random element from a list, such that each element in
> the list is equally likely to be selected.
> 
>   sounds trivial, yes?  except here's the extra condition.  you're
> given the list elements only *one at a time*.  you're not allowed to
> store them, and you have no idea how many are coming.  and yet, you
> still need to pick a random element out of that list.
> 
>   thoughts?
> 
> rday
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