Re: find words not in an array

From: Jürgen Exner (jurgenex_at_hotmail.com)
Date: 03/28/05 

Date: Mon, 28 Mar 2005 06:18:17 GMT

r wrote:
> if I have 2 arrays, @wordlist and @testlist, how can I create a third
> array that contains the words from @testlist that are not common to
> @wordlist?
> I thought I might use grep but can't figure it out.

No, grep isn't quite the right tool. For questions like that a hash is
usually the datastructure of choice.
In this particular case you may want to start with the "perldoc -q
intersection". This FAQ computes the symmetric difference, so you will have
to modify the answer slightly.
Or you simply grab the proper set module from CPAN.

jue

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