1. Topic 11
Heaps and Tries

2. Announcements Grading Homework 5 solutions will be up today
Homework 3 to be graded by today
Homework 4 to be graded tomorrow/Thursday
Homework 5 solutions will be up today
Test in 1.5 weeks
Online students: make sure you can take the test on Thursday/Friday.
Participation
Schedule

3. Homework 5 solutions

6. Heaps
Priority Queues
Definition:

7. Heap Property

8. Representation/Implementation

9. Array attributes

10. Example representation

11. Calculating Parent/Child

12. Heap Operations: Insertion

15. Pseudocode

16. Heap Operations: delete-max/min

19. Announcements Mid-semester Survey (soon) Practice quizzes to be posted
Participation questions?

20. Heap Operations: build-heap

23. Example

26. Pseudocode

27. Heap Sort

28. Basic Idea

29. Example

30. Pseudocode

31. Stability
Original
Sorted

32. Tries

33. Definition
Definition:

34. Adding fixed-length keys

41. Alphabet Trie (alphabet from English alphabet)

45. Analysis (compressed tries)
Search
Insertion
# nodes s

46. Uses
Sort?
Search?

47. Announcements Participation due Past quizzes and survey are up
No more programs
Test is next week
Online students: take midterm the same time as midterm 1
Heap sort best case – O(nlogn)

48. Participation (problem 1)

49. Participation (problem 2)

52. Searching for Suffixes

53. Example