sub thread
{
print '<ul>';
for my $node (sort {$b <=> $a} keys %created){ # for all nodes
# if doesn't have a parent and isn't a user
if((!$parent{$node}) && ($nodetype{$node} ne 'user')){
  if($created{$node}=~/^(....)(..)(..)(..)(..)(..)$/){
     $created{$node} = "$4:$5:$6 $2/$3"
     }
  print qq~$types{$nodetype{$node}} ($created{$node})<br>
  $content{$node}
  by $whom{$author{$node}}<br>~;

  my$d = 0;
  for my $p1 (sort {$a <=> $b} keys %parent){ # re
    if( ($parent{$p1} == $node) ){
       unless($d > 0){ print '<ul>'}
       print qq~$content{$p1} 
       by $whom{$author{$p1}}<br>~;
       $d++;
       
      my$e = 0;
      for my $p2 (sort {$a <=> $b} keys %parent){ # re(2)
        if( ($parent{$p2} == $p1) ){
           unless($e > 0){ print '<ul>'}
           print qq~$content{$p2} 
           by $whom{$author{$p2}}<br>~;
           $e++;
             
           my$f = 0;
           for my $p3 (sort {$a <=> $b} keys %parent){ # re(3)
             if( ($parent{$p3} == $p2) ){
                unless($f > 0){ print '<ul>'}
                print qq~$content{$p3} 
                by $whom{$author{$p3}}<br>~;
                $f++;
                        }
                     }
                  if($f > 0){ print '</ul>'}
                  }
               }
            if($e > 0){ print '</ul>'}
            }
         }
      if($d > 0){ print '</ul>'}
      }
   }
print '</ul>';
}