endorder
(*action)(root, endorder, level);
if (order == endorder || order == leaf) {
if (order == endorder || order == leaf) {
if (order == endorder || order == leaf) {
if (order == endorder || order == leaf) {
if (order == endorder || order == leaf) {
if (order == endorder || order == leaf) {
(*action)(root, endorder, level, cookie);