1. 10.3 Tree Transversal

2. Pre/post fix notation and order See handout. a.bc.d e f g h i j k

3. Preorder transversal- root first, then left to right a.bc.d e f g h i j k

4. Inorder transversal- left tree, then root, then rest of trees- left to right a bc d e f g h i j k

5. Postorder transversal- left to right, then root last a.bc.d e f g h i j k

6. Infix, prefix, and postfix See handout Infix order is ambiguous – so parentheses are required Prefix and postfix are not– so parentheses are unnecessary Prefix- “Polish notation” – Read from R to L – Operations are on the L Postfix – Read from L to R – Operations are on the R

7. Example– transverse in 3 ways, and evaluate each notation +  * 32 5 2 Preorder- prefix Inorder-infix Postorder-postfix

8. Example- prefix Evaluate a prefix expression + - * 2 3 5 /  2 3 4

9. Ex- postfix 7 2 3 * - 4  9 3 / +

10. Example– transverse in 3 ways, and evaluate each notation +  * 52 3 4 Preorder- prefix Inorder-infix Postorder-postfix -  *

11. Find the value of each prefix expression (R to L,operations on the L) - * 2 / 8 4 3  - * 3 3 * 4 2 5

12. Find the value of each prefix expression (R to L,operations on the L) + -  3 2  2 3 / 6 – 4 2 * + 3 + 3  3 + 3 3 3

13. Find the value of each postfix expression (L to R, operations on R) 5 2 1 - - 3 1 4 + + *

14. Find the value of each postfix expression (L to R, operations on R) 9 3 / 5 + 7 2 - * 3 2 * 2  5 3 – 8 4 / * -