#!/usr/bin/perl -w
use strict;

my $grp = qr/\[\d+-\d+\]/;

for (<DATA>) {
    print if /\d+\.\d+\.$grp\.(\d+|$grp)/;
}


__DATA__
123.145.[146-149].2
135.168.[10-115].[0-125]
135.168.12.[0-125]

##</code><code>##

#!/usr/bin/perl -w
use strict;

my $grp = qr/^123\.145\.(\d+)\.(\d+)$(??{ $1 >= 146 && $1 <= 148 ? '' : 1})/;

for (<DATA>) {
    print if /$grp/;
}


__DATA__
123.145.130.3
123.145.146.3
123.145.147.3
123.145.148.3
123.145.149.3