As trammell pointed out index() returns 0 if the sought for string is the beginning. Try this: 
@Array1 = qw{XXX FFF ZZZ AAA BBB QQQ LLL JKK III CCC DDD DCD};
@Array2 = ("XXX BBB AAA CCC DDD EEE", "FFF NNN JKK III LLL QQQ");


foreach(@Array1)
{
        $string1 = $_;
        foreach(@Array2)
        {
                my $string2 = $_;
                my $result = index($string2, $string1);
                print $string1, ($result >= 0 ? " IS    " : " IS NOT",
+ " found in "), $string2, "\n";
        }
}

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In reply to Re^2: Substring comparison by flaviodesousa
in thread Substring comparison by schtinkfist893

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