while (@data = $sth->fetchrow_array()) {

      if ($data[1] ne $tempstate) {
         undef (@cities);
         push (@cities, $data[0]);
         $states{$data[1]} = [ @cities ];
         $tempstate = $data[1];
         $tempcity = $data[0];
         
      } elsif ($data[0] ne $tempcity) {   
         push (@cities, $data[0]);
         $states{$tempstate} =  [ @cities ];      
         $tempcity = $data[0];
      }
  
 }