Hello, I have a program which is unable to read data (protein fasta seq.). Please make me error free so that I could run the program

use strict;
use warnings;
my $pp = qr/(?: (\w) (?1) \g{-1} | \w? )/ix;

local $/ = '';

while (<DATA>) {
    chomp;
    my ($header, @lines) = split "\n";
    my $data = join '', @lines;

    print "$header\n$data\n";

    while ($data =~ /(?=($pp))/g) {
        print "$-[0] - $1\n" if length($1) > 2;
    }
}

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In reply to Perl program for finding palindromes from protein fasta file by Rajkishore

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