Hi Monks.i have a error that i dont understand what is it? please help me.

#!/usr/bin/perl -w
use strict;
my @AoA;     

open (IN,'<result');
while(<IN>){
my @chunks = split;
    push @AoA, [ @chunks[1..$#chunks]];
}

my %neighbours;
for my $domain (@AoA) {
    for my $idx (0 .. $#$domain) {
        my @near = grep {$_ >= 0 && $_ <= $#$domain} $idx - 1, $idx + 
+1;
        push @{$neighbours{$domain->[$idx]}}, map {$domain->[$_]} @nea
+r;
    }
}


open (DOMAINLIST,'<domainlist') or die "cannot open 'domainlist'becuas
+e:$!";

   chomp(my @domain=<DOMAINLIST>);
    for my $domain(@domain){
    my @array=@{$neighbours{$domain}};
    
    @array=removeduplicates(@array);
    my $number=scalar @array;
     print "Domain $domain.......$number\n";
}

sub removeduplicates{
my @array=@_;
my %seen;
$seen{$_}++ for @array;
my @unique = keys %seen;
return @unique;
}

[download]
the error is :cant use an undefined value as an ARRAY reference in line 24.

In reply to array references by Anonymous Monk

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