1. INTRODUCTION TO DATA STRUCTURES AND ALGORITHMS Marcus Frean School of Engineering and Computer Science, Victoria University of Wellington COMP 103 2014-T2 Welcome

2. 2 PEOPLE  Co-ordinator: Marcus Frean [Co227, 463-5674] Office hours: 9-11am Fridays  Lecturer: Marcus Frean  Senior Tutor: Zarinah Amin [Co343, 463-5936]  Email: firstname.lastname@ecs.vuw.ac.nzfirstname.lastname@ecs.vuw.ac.nz  Course URL: http://ecs.victoria.ac.nz/Courses/COMP103_2014T2  Class Rep:YOUR NAME HERE? 2

3. 3 ADMINISTRATION  Prerequisite:  You need to have passed COMP102 with a B- or better, or passed COMP112.  If you did not meet this, you can take 102/112 again (COMP102 is offered both trimesters, but not over the summer) 3

4. 4 HELPING YOU SUCCEED 4

5. 5 LECTURES Mon-Tue-Thur in MCLT103  Slides  printouts provided in class  also on course webpage  I’m looking into video – should be fine  Goals:  Provide a framework for your learning  Provide explanations/demonstrations  SLIDES NOTES TEXTBOOK 5

6. 6 TUTORIALS  Taken by a successful former student of 103  Starting next week  various locations  What happens:  Quick quiz  work with peers to understand the tricky bits  The tutor will set topical problems – you will work out answers, get feedback, discuss with the tutor and each other...  Our aim: help you to understand both lectures and assignments better 6

7. 7 ASSIGNMENTS  Critical for your learning!  10 Assignments, total 20%  out: Mondays (in lecture)  due: 3pm on Monday of the following week (submitted electronically)  Solutions will be available in the Monday lecture too.  Late assignments can’t be marked. 7

8. 8 ASSIGNMENTS Some THEMES for the assignments:  Graphical editors: painting, diagrams, family trees..  Processing files of TEXT DATA: analysing data files, stories, web pages etc.  Simulations: programs that implement bits of REAL world  Do it yourself – no pairing up  You can work in the ECS labs at all sorts of hours of day and night  Register on a lab computer to obtain a user login (if you haven’t already got one from 102/112) 8

9. 9 HELP DESK  Intended for small groups, of about 1...  One-on-one help with assignment work.  Close to the labs but not in them: print out your code, highlight what you want to discuss.  Where and When: to be announced 9

10. 10 TEXT BOOK  JAVA FOUNDATIONS: Introduction to Program Design & Data Structures - by Lewis, DePasquale and Chase - 2 nd or 3 rd edition is best  SAME textbook as comp 102/112  COMPLEMENTS lectures and assignments (but we do not always follow the text closely) 10

11. 11 WEB RESOURCES  FORUM:  Post questions  Collaborate and help each other  Course staff monitor and answer when appropriate  NO posting chunks of ANSWERS to assignments!  all the lecture notes and assignments  videos (soon)  links to Java reference material  tips on getting Java and BlueJ working at home  previous tests and exams 11

12. 12 ASSESSMENT  10 Assignments[20%]  Mid-term test[20%] 45 mins, Thurs 21 st August  Tutorials – get there![2%]  Final Exam [58%] 2 hours, in exam period Mandatory Requirements:  Submit reasonable attempt for at least 7 out of 10 Assignments (all submitted assignments may be used for borderline cases and aegrotats)  At least ‘C-’ grade overall to PASS  (and at least a D in the exam) 12

13. 13 PLAGIARISM UNACCEPTABLE  We want you to LEARN, TALK to each other, learn TOGETHER, and HELP each other, but PLAGIARISM is UNACCEPTABLE!  Got help from anybody other than lecturer or tutor ? STATE IT ON THE ASSIGNMENT!  Copied bits of code from anywhere other than lecture slides or textbook ? STATE IT ON THE ASSIGNMENT! 13

14. 14 SAFETY in the LABS  Computer Labs are the most dangerous labs in the university  More people are injured at computer labs than in any other science lab!  Your computer at home is probably even more dangerous! AAAAAaaaaargh! OOS is rampant and debilitating  Read the POSTERS in the lab  See student health quickly if you get problems 14

15. 15 QUICK RECAP  What was in comp 102/112?  Classes, Objects, Fields, Methods  Conditionals, Loops (if, if...else, for, while, do..while)  Using variables, reading input, writing, drawing  Algorithm design  Using GUI’s (Graphical User Interface)  Arrays, and using ArrayList Revise these concepts to get a head-start! 15

16. 16 Some Basic Terms  Algorithm: step-by-step process to solve a problem (pseudocode: part code, part English)  Program: actual implementation of an algorithm in a programming language  Data Structure: the way data is structured or organized (example: Array)  Collection: an object that serves as a repository for other objects (like a “container”) 16

17. COLLECTIONS  Big chunks of real life involve what we could call Collections, and this is reflected in programs written to help real life:  Collections of books, music, photos, clothes,...  Organized in a way to ease access and use items  Some STANDARD types of Collections we use in our programs:  List, Set, Bag, Stack, Queue, Trees, Map 17

18. 18 Varieties of collection  Different structures  No structure – just a collection of values  Linear structure of values – order matters  Hierarchical structures  Different constraints for accessing elements  get, put, remove anywhere  get, put, remove only at the ends, or only at top (and so on). 18

19. WHAT CAN YOU EXPECT...  Using and understanding the current Java Collections Library  Creating your own Collections  How to add, remove, search, sort,... efficiently So this is what 103 is about:  The fundamental data structures of computer science  The crucial algorithms on those structures  Especially the efficiency of those algorithms 19

20. 20 Course Overview – Part 1 Programming with Linear collections  Different Kinds of collections:  Lists, Sets, Bags, Maps, Stacks, Queues, Priority Queues  Implementing, using, sorting, and searching these Linear collections... 20

21. 21 Course Overview – Part 2 Programming with Hierarchical collections  Building, traversing Tree-structured collections  Re-implementing linear collections  with binary search trees  with partially ordered trees  with hash tables 21

22. 22 RECURRING THEMES  Good Design Choosing appropriate implementations How do you get it right first time ?  Efficiency How fast is it ? How much memory does it take ? Analysis and benchmarking 22