use CGI qw(:standard);

my $numb;
print header();

if ($numb = trim(param('numb'))) {
   print start_form();
   print hidden(-name=>"hidden$_") 
      for map { sprintf("%04d",$_) } (0..$numb);
   print submit('stumbit'), end_form();
}
elsif (param('stumbit')) {
   print ul(map {li($_)} grep /^hidden/, param());
   print start_form(), submit('try again'), end_form();
}
else {
   print "Enter number of hidden fields to create: ",
      start_form(), textfield('numb'), 
      submit('go'), end_form();
}

sub trim {
   my $it = shift;
   $it =~ s/^\s*//o;
   $it =~ s/\s*$//o;
   return $it;
}
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jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)