The idiomatic way of eliminating duplicates creates an hash of counts as a byproduct. 

my %counts;
my @uniqueIPs = grep !$counts{$_}++, @ipAddresses;

for my $ip (sort @uniqueIPs) {
   print("$ip ($counts{$ip})\n");
}

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In reply to Re: Counting unique instances from Array Sort by ikegami
in thread Counting unique instances from Array Sort by ewhitt

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