Re: CArray, CStringArray, CMap, ...

From:
"Jonathan Wood" <jwood@softcircuits.com>
Newsgroups:
microsoft.public.vc.mfc
Date:
Thu, 9 Apr 2009 14:04:03 -0600
Message-ID:
<#RXrZ5UuJHA.3520@TK2MSFTNGP04.phx.gbl>
"Tom Serface" <tom@camaswood.com> wrote in message
news:80B6C567-A7EC-4E0F-8497-F176CCC7055E@microsoft.com...

I think there is some trade off depending on how often you want to search.
For example, if I seldom search, but add a bunch of items all at once
sorting just takes up a bunch of time when each item is added. In that
case I'd likely use a map instead with a hash. I've also found I can
search through like 100K items in a CObArray in a second or so ... so an
occasional search is not really that objectionable. However, if the
program is constantly searching then a better mechanism is needed of
course.


Hashes always seem like a pain to me in that it's not always easy to get a
good hash key, and data tends to use a lot of extra memory to have enough
slots for a good hash key (although this can be mitigated somewhat).

A good sorted array will perform a look up when inserting an item rather
than resorting the entire list and I've found that to be a good approach for
many applications.

Of course, it's always a trade off depending on your particular
requirements.

--
Jonathan Wood
SoftCircuits Programming
http://www.softcircuits.com
http://www.softcircuits.com/blog/

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