@aa = @bb = (1) x $nn;

##</code><code>##

  push @ready, "@aa\n";
  ...
  push @ready, "@aa\n";
  ...
  push @ready, "@bb\n";

##</code><code>##

  for (my $kk = $nn; $kk > 0; --$kk) {
    ...
  }