my %topfive;
  for my $c (keys %code) {
      my %user;
      for my $row (@{$code{$c}}) {
         # Note: this assumes that the userid field
         # is unique to each user.
         $user{$$row{userid}}{count}++;
         $user{$$row{userid}}{name} = $$row{username};
      }
      $topfive{$c} = [(sort {
        $$b[2] <=> $$a[2]
      } map {
        [$_, $user{$_}{name}, $user{$_}{count}]
      } keys %user)[0 .. 4]];     
  }