btw, the compare function is suppose to return 1, 0, +1, not just 0 and 1, so I expect your sort has some amount of randomness to it.
Maybe you want something like:
sub intermix {
my $a_prime = join('.', reverse(split(/\./, $a)));
my $b_prime = join('.', reverse(split(/\./, $b)));
$a_prime cmp $b_prime
}
my @list = ('10.1.1.1', '10.1.1.2', '10.2.2.1', '10.2.2.2');
@list = sort intermix @list;
use Data::Dumper;
print Dumper(@list);
__END__
output
======
$VAR1 = '10.1.1.1';
$VAR2 = '10.2.2.1';
$VAR3 = '10.1.1.2';
$VAR4 = '10.2.2.2';
Almost the same, but more efficient:
sub intermix {
my $a_prime = reverse($a);
my $b_prime = reverse($b);
$a_prime cmp $b_prime
}
my @list = ('10.1.1.1', '10.1.1.2', '10.2.2.1', '10.2.2.2');
@list = sort intermix @list;
use Data::Dumper;
print Dumper(@list);
__END__
output
======
$VAR1 = '10.1.1.1';
$VAR2 = '10.2.2.1';
$VAR3 = '10.1.1.2';
$VAR4 = '10.2.2.2';
This is the same thing as the last, but probably more efficient, especially for longer lists:
my @list = ('10.1.1.1', '10.1.1.2', '10.2.2.1', '10.2.2.2');
@list = map { $_>[0] }
sort { $a>[1] cmp $b>[1] }
map { [ $_, ''.reverse($_) ] }
@list;
use Data::Dumper;
print Dumper(@list);
__END__
output
======
$VAR1 = '10.1.1.1';
$VAR2 = '10.2.2.1';
$VAR3 = '10.1.1.2';
$VAR4 = '10.2.2.2';
Note: Given addresses of the form 'a.b.c.d', the above snippets only work well if there is there is a common 'd' of for every 'a.b.c' in the list.
