sub arrarycomp {
  my ($x, $y) = @_;
  my $arrmin = $#$x;
  $arrmin = $#$y if $#$y < $arrmin;
  my $result;
  for (0 .. $arrmin) {
    if ($result = $$x[$_] cmp $$y[$_]) {
      return $result;
    }
  }
  return $#$x - $#$y;
}

@out = sort {arrarycomp($a, $b)} @in;