I've got a situation where there are a hundred items, either true or false.

I've got the old list of which ones are true or false, and I've edited it using a web form, probably removing some from the "true" list and adding others to it.

Having submitted the form, what's the best way to reset the list correctly?

I did it like this:

I made a hash of 100 entries all set to zero, then did a foreach on the list of old items, and set the right values to 1.

Then I made a hash of 100 entries all set to zero and did a foreach loop on the list of new items, setting the right values to 1.

Then I went through the hash keys like this: 

foreach $entry(@a){
 if ($oldhash{$entry}==1 && $newhash{$entry}==0){
     #  push it into an array of deletions to be made
 } elsif($newhash{$entry}==1 && $oldhash{$entry}==0){
      # ditto array of additions to be made
 }
}

[download]

I've been staring at this code for a while and I can't figure out if that's a dumb way to do it or not, but it feels kind of dumb.

Is there a smarter way?
--

Edit: chipmunk 2002-02-24

In reply to comparing two hashes by Cody Pendant

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