sub do_the_sort {
  my @aa = split /\//, $a;
  my @bb = split /\//, $b;
  for ( 0 .. $#aa ) {
    return 1 unless defined $bb[$_];
    my $zz = $aa[$_] <=> $bb[$_];
    return $zz if $zz;
  }
  -1;
}

my @y = sort do_the_sort @x;