$distance = 25;

for $i (0..$#data) {
  my $quick_reject_routine = 
      make_quick_reject($data[$i]->[1], $data[$i]->[2], $distance);
  my $quick_accept_routine =
      make_quick_accept($data[$i]->[1], $data[$i]->[2], $distance);
  for $record (grep(! $quick_reject_routine->($_->[1],$_->[2]), 
                    @data[$i+1..$#data])) {
    if ($quick_accept_routine->($record->[1],$record->[2])
        or
        long_acceptance_routine($record, $data[$i], $distance) {
      # write it to some file or other
    }
  }
}