Hi, I am trying to print the values of hfr_genes.txt only if it is present in gene_list.txt but the code is not working and i get the error 'use of uninitialized value in array'. pls help me. thanks. 
#!/usr/bin/perl
use 5.010;
use strict;
use warnings;
open GL,'gene_list.txt';
open HFR,'HFR_genes.txt';
use List::MoreUtils qw(first_index indexes);
my @gl=<GL>;
my @hfr=<HFR>;
chomp @gl;
chomp @hfr;
my $a;
for($a=0;$a<=scalar(@hfr);$a++)
{
my @matching_indices=indexes {$hfr[$a]}@gl;
my @matching_values=@gl[@matching_indices];    
print "$matching_indices[$a]";
}

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In reply to use of uninitialized value in array by rocketperl

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