We can use some of the standard functions loaded by "Socket" module to handle ip addresses:

use Socket;
use strict;
use warnings;

my %stat;
my @addr = qw(10.0.0.1
              10.0.0.2
              10.0.0.3
              192.168.1.5
              192.168.1.6
              192.168.10.3
              192.168.10.4
              192.168.10.5);
$stat{inet_ntoa(substr(inet_aton($_), 0, 3) . "\0")} ++ foreach (@addr
+);
print "$_ has $stat{$_} nodes\n" foreach (keys %stat);

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In reply to Re: Summarizing an array of IP's by pg
in thread Summarizing an array of IP's by carric

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