You've already got a pointer to the QA section.

Another solution (that I didn't see mentioned there) is to transfer elements of one array into a hash, and use that.

Such a method uses more memory space but is faster (unless you use so much memory you start swapping :-)

The code would look somewhat like this:

map($a1{$_}=1,@a1); # create %a with elements from @a1
@a2=grep(!defined($a1{$_}),@a2); # returns those elements of @a2 that 
+don't 
                        # have a hash element in %a1 therefore they 
                        # do not exist in @a1.

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In reply to Re: How do I compare two arrays? by matija
in thread How do I compare two arrays? by luoina

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