my @mystack;
my $i = 1;
tree_children('0');
sub tree_children {
  my $r = shift;
  # push(@mystack,$obj{$r}) unless $r eq '0';
  if ($children{$r}) {
    for (@{ $children{$r} }) {
      push(@mystack,[$_,$obj{$_}]);
      $i++;
      tree_children($_);
      $i--;
    }
  }
}