...so that I can then compare this new array with a third array and repeat the process

To determine what elements are common to a set of arrays you should use hashes, since that is the mechanism best suited to checking if values have previously been encountered.

$h{$_}++ for (@array1,@array2);

@common_elements = grep {$h{$_} > 1} keys %h;

print "@common_elements";

[download]

With a little imagination you could make this generic to operate on N arrays, not just two.

In reply to Re: comparing arrays by EdwardG
in thread comparing arrays by Becky

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