/* Prints the structure of |node|,
   which is |level| levels from the top of the tree. */
static void
print_tree_structure (const struct bst_node *node, int level)
{
  /* You can set the maximum level as high as you like.
     Most of the time, you'll want to debug code using small trees,
     so that a large |level| indicates a ``loop'', which is a bug. */
  if (level > 16)
    {
      printf ("[...]");
      return;
    }

  if (node == NULL)
    return;

  printf ("%d", *(int *) node->bst_data);
  if (node->bst_link[0] != NULL || node->bst_link[1] != NULL)
    {
      putchar ('(');

      print_tree_structure (node->bst_link[0], level + 1);
      if (node->bst_link[1] != NULL)
        {
          putchar (',');
          print_tree_structure (node->bst_link[1], level + 1);
        }

      putchar (')');
    }
}

/* Prints the entire structure of |tree| with the given |title|. */
void
print_whole_tree (const struct bst_table *tree, const char *title)
{
  printf ("%s: ", title);
  print_tree_structure (tree->bst_root, 0);
  putchar ('\n');
}