use strict;
use Data::Dumper;

my $con = qr/[b-df-hj-np-tv-xz]/;
my $vow = qr/[aeiouy]/;

my $ncon = qr/[^b-df-hj-np-tv-xz]/;
my $nvow = qr/[^aeiouy]/;

my $x = 'battlestar galactica';
my $y = 'silly ahab';

($x,$y) = map{swap($_)}($x,$y);

print Dumper([$x,$y]);

sub swap {
    my $x = shift;
    if($x =~ /(${con})(${ncon}*?\b)(${ncon}*?)(${con})/){
        $x = $`.$4.$2.$3.$1.$';
    } $x
}