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From: wengland@stephsf.stephsf.com (Bill England)
Newsgroups: comp.lang.perl
Subject: The best way to search an array ?
Keywords: detab
Message-ID: <443@stephsf.stephsf.com>
Date: 26 Nov 90 01:55:08 GMT
Organization: Stephen Software Systems, Inc., Tacoma WA
Lines: 50


  What is the best method for discovering if a string is in
  a given set of strings?  For example say you want to verify
  that the string 'WA' is a valid two char state abreviation?

  I can think of at least four methods ...

  Method      Description

    1       Search a string that contains all two letter state names;
            Here you would prefix and suffix the state var and
            then search the string.  Something like ;
			...
			$state = '~AK~AL~AR~AZ~CA~CO~...';
			$search_string = '~'.$prove_state.'~';
            if( /$search_string/ eq $state) { ... }

    2       Build an associative array %state so that you have;
            $state{'AK'}="Alaska";
            $state{'AL'}="Alabama";
            $state{'AR'}="Arkansas";
            $state{'AZ'}="Arizona";
            $state{'CA'}="California";
            ...
            Then test for the existance of $state{$prove_state}.
            ( Has disadvantage of extra bagage if you don't need the
              states full name.   )

    3       Build a simple array and then search with a foreach
                @state = ('AK','AL','AR','AZ','CA', ...);
                foreach $st(@state){
                    last if $st eq $prove_state;
                }

    4       The same as 3 above but, use a binary search instead of
            a linear search.



   Which of the above would be the best to use in perl? 

   Is there a better way ???

 +--------
 |  Bill England
 |  wengland@stephsf.COM
 |
  * *      H -> He +24Mev
 * * * ... Oooo, we're having so much fun making itty bitty suns *
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