Hello folks, Can one of you Monkish gentlemen help me with this? I am stuck with a recursion issue here. Basically i am trying to print out a spreadsheet of parents and children of this structure:

A1

A1 B1

A1 B1 C1

A1 B1 C1 D1

A1 B1 C2

A1 B1 C3

A1 B1 C4 D2

A1 B2

A1 B2 C5 D3

Here B1 is child of A1 and C1 is child of B1. B1 has many children C1,C2,C3 C4. My program succeeds till line 4. The moment the last child doesn't have a grand child under it, it stops. How could I make it go back and keep on printing out till the end? Here is my actual code snippet: $top calls the first asset A1 which is parent of B1,B2 etc. 
my @line;
foreach (my $top = $top_sth->fetchrow_hashref)
  {
  $line[0]= $top->{guid};
  push @line,$top->{title};
  $exchange->stdxls_write($exchange->stdxls_row(), \@line);
  print STDERR "Level1 ".$top->{title}."\n";

  child_levels($top->{asset_id},@line);
  }
$workbook->close();

sub child_levels
{
  my ($asset_id,@line) = @_;

  my $child_sth = $dbh->prepare('
    SELECT asset_id
      ,title
      ,seq
      ,guid
      ,parent_id
    FROM asset
    WHERE parent_id = ?
    ORDER BY seq
  ') or die $dbh->errstr;

  $child_sth->execute($asset_id) or die $child_sth->errstr;
  foreach (my $child = $child_sth->fetchrow_hashref)
    {
    $line[0]= $child->{guid};
    push @line,$child->{title};
    $exchange->stdxls_write($exchange->stdxls_row(), \@line);
    child_levels($child->{asset_id},@line);
    }

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In reply to Recursive program by newtoperl101

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