1. Printing a search tree in order
When is root printed?
After left subtree, before right subtree.
void Visit(Node * t) {
if (t != 0)
Visit(t->left);
cout << t->info << endl;
Visit(t->right); }
Inorder traversal
“llama”
“tiger”
“monkey”
“jaguar”
“elephant”
“giraffe”
“pig”
“hippo”
“leopard”

2. Tree traversals Different traversals useful in different contexts
Inorder prints search tree in order
Visit left-subtree, process root, visit right-subtree
Preorder useful for reading/writing trees
Process root, visit left-subtree, visit right-subtree
Postorder useful for destroying trees
Visit left-subtree, visit right-subtree, process root
“llama”
“tiger”
“monkey”
“jaguar”
“elephant”
“giraffe”

3. Printing a tree in pre order
When is root printed?
before left subtree, before right subtree.
void PreVisit(Node * t) {
if (t != 0)
cout << t->info << endl;
PreVisit(t->left);
PreVisit(t->right); }
preorder traversal
“llama”
“tiger”
“monkey”
“jaguar”
“elephant”
“giraffe”
“pig”
“hippo”
“leopard”

4. How high is stack of calls (non-null t)?
void PreVisit(Node * t) {
if (t != 0) {
cout << t->info << endl;
PreVisit(t->left);
PreVisit(t->right); }
void PreVisit(Node * t) {
if (t != 0) {
cout << t->info << endl;
PreVisit(t->left);
PreVisit(t->right); }
void PreVisit(Node * t) {
if (t != 0) {
cout << t->info << endl;
PreVisit(t->left);
PreVisit(t->right); }
void PreVisit(Node * t) {
if (t != 0) {
cout << t->info << endl;
PreVisit(t->left);
PreVisit(t->right); }
PreVisit(root)
“jaguar”
“elephant”
“giraffe”
“hippo”
“leopard”
void PreVisit(Node * t) {
if (t != 0) {
cout << t->info << endl;
PreVisit(t->left);
PreVisit(t->right); }

5. Printing a tree in post order
When is root printed?
after left subtree, after right subtree.
void PostVisit(Node * t) {
if (t != 0)
PostVisit(t->left);
PostVisit(t->right);
cout << t->info << endl; }
preorder traversal
“llama”
“tiger”
“monkey”
“jaguar”
“elephant”
“giraffe”
“pig”
“hippo”
“leopard”