sub slow_match {
  my($hash_ref_1,$hash_ref_2) = @_;

  while ( my($pattern,$high_lvl_id) = each(%hash1) ) {
    my $match = qr/\b$pattern\b/;
    while ( my($text_id,$text) = each(%hash2) ) {
      if ($text =~ $match) {
         $$hash_ref_1{$text_id} .= ':'.$high_lvl_id;
         foreach my $part (split(/\s/,$pattern)) {
            $$hash_ref_2{$text_id} -> {$part} = 0;
         }
       }
     }
   }
}