Well, line 24 is:

my @array=@{$neighbours{$domain}};

As @{...} is an array dereference, it would appear that $neighbours{$domain} is undefined. I can't tell more without seeing your input (and desired output), but you could at least bandage this with something like: 

    for my $domain(@domain){
    next unless exists $neighbours{$domain};
    my @array=@{$neighbours{$domain}};

[download]

Of course, this explicitly skips any element of @domain where %neighbours is uninitialized, which may be problematic for your case. You might also consider something like: 

    for my $domain(@domain){
    my @array=exists $neighbours{$domain} ? @{$neighbours{$domain}} : 
+();

[download]

where this second option silently swallows domain misses. See perlreftut for more on references.

In reply to Re: array references by kennethk
in thread array references by Anonymous Monk

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