Normalise/demormalise:

use strict;
use warnings;

my @ips = qw(123.156.89.12 12.245.67.1 12.45.67.180 12.145.66.20);

@ips = map {sprintf "%d.%d.%d.%d", split /\./} sort
    map {sprintf "%03d.%03d.%03d.%03d", split /\./} @ips;

print join "\n", @ips;

[download]

Prints:

12.45.67.180
12.145.66.20
12.245.67.1
123.156.89.12

[download]
DWIM is Perl's answer to Gödel

In reply to Re: How to sort IP addresses by GrandFather
in thread How to sort IP addresses by Anonymous Monk

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