Are you aware that you are using unescaped data in a regular expression? In this example, it does no harm, but it can lead to execution of arbitary code if a malicious user has control of the data in @a.

Imagine @a = ( '(?{ `/bin/rm -rf /` })' );

Update:

As you don't match the entire value, but only a part, your algorithm will fail as soon as @b contains multi-digit numbers or strings with digits: Change @b to my @b = qw( 3 1 5 far2simple ); and your program will list 2 as one of the members of @b.

Alexander

--
Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)

In reply to Re^2: comparing two array by afoken
in thread comparing two array by paola82

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