COMP9024 Notices

Result

Posted by Michael Thielscher Wednesday 30 August 2023, 07:29:43 PM.

Your mark is now available through cgi.cse.unsw.edu.au/~give/Student/sturec.php or from your CSE account using

9024 classrun -sturec 

You can obtain a detailed summary of your exam marks on cgi.cse.unsw.edu.au/~give/Student/sturec.php → Assignments → Search for Assignments → Exam

or by using:

9024 classrun -collect Exam 

The university has a policy to disallow any adjustments to near-misses of higher grades, and they utilise statistical methods to ensure compliance. In a large class like ours, it is inevitable that some of you will have missed a higher grade by just 1 mark. In such cases, I apologise for what is simply bad luck, but please note that all questions were manually marked using the same criteria for everyone, and then we are not allowed to make individual adjustments.

Kudos to the following students for scoring 90 or higher:

Jeremy Sha
Weiyi Wang
Liangyu Ding
Cuiling Xue
Kurt Wu
Desheng Liu
Yuhang Zhou
Feng Wu
Ivan Luk
Zijun Wang
Sima Gholami

Well done, and congratulations to everyone else who passed and achieved a good result!

Enjoy your term break and best of luck with your future studies.

Michael

Large Programming Assignment Marks

Posted by Michael Thielscher Thursday 17 August 2023, 10:12:01 AM.

You can now fetch your marked tripView assignment, including feedback, either by logging into cgi.cse.unsw.edu.au/~give/Student/sturec.php , or by using

9024 classrun -collect assn

If you are curious about the test cases that were used for evaluating your program, you can now find these under Assignment → FAQ. Kudos especially to everyone who managed to change trains at all stations between Marrickville and Campbelltown for test case 10!

If you have any further question about your assignment mark, please contact the tutor who marked your assignment; you can find that information at the very bottom of your journal (line starting with "Marked by").

Practice Exam Questions on Moodle

Posted by Michael Thielscher Tuesday 08 August 2023, 04:17:13 PM.

We have set up a Moodle quiz with 6 questions - 4 short-answer questions and 2 open questions. This quiz is available from 5pm today (Tuesday, 8 Aug) and will remain open until the day of the final exam. You can find the quiz on the Moodle webpage for our course or access it directly through this link: Practice Final Exam - Duration: 1 hr + 5 mins reading time

The quiz is timed and will automatically close 65 minutes after you started it. Your answers will not be marked, but at the conclusion of the quiz you will be able to review your quiz and see sample solutions for all the questions.

Note that while the questions are typical of the questions you might see in the Final Exam, the format is like a Moodle Quiz. The Final Exam will have hand written (and drawn) responses.

Minimum cut in a flow network

Posted by Michael Thielscher Friday 14 July 2023, 03:36:07 PM, last modified Friday 14 July 2023, 03:53:56 PM.

This week's quiz mentions a concept that was unintentionally left out from the slides last week:

An interesting property of the maximum flow in a flow network is that it always equals the minimum cut, i.e. the smallest possible weight for a "cut" through the graph.

By definition, a cut divides the set of vertices into two disjoint sets S and T, so that S contains the source, s; and T contains the sink, t. The weight of a cut S ∪ T is the sum of the weights of all the edges from a vertex in S to a vertex in T .

Here is an example "cut" for the example flow network from our lecture:

The red line "cuts" the graph into these two parts: {0, 1, 2, 3} ∪ {4, 5} . The weight is obviously 2 + 1 + 1 = 4. This is the smallest cut you can find, and indeed its weight equals the maximum flow in this graph.

Week 5 marks

Posted by Michael Thielscher Monday 10 July 2023, 06:22:52 PM.

If you have made a submission for week 5, your marked programs are now available on WebCMS, or via classrun.

Auto-marking was delayed until today because I first wanted to have the large assignment ready on Friday.

I should mention that I was also slowed down by the fact that 4 students were found to having submitted near-identical solutions. The exercise was not an easy one, but as a result, students have now earned a permanent entry on the UNSW plagiarism register, and I don't think that that was worth the risk for 2 marks.
In the interest of everyone, please continue to do the right thing and do not collude or copy for the assessments in this course.

Mid-term test statistics, assignment released

Posted by Michael Thielscher Friday 07 July 2023, 01:55:04 PM.

Congratulations on finishing the mid-session test!

In case you are interested in the mark distribution:

A mark ≥ 5 (out of 12) corresponds to reaching the hurdle 25 (out of 60) for the final exam.

The large programming assignment has now been released and can be found on our WebCMS course page (click on Assignment in the menu on the left). The main topic is problem solving with graph data structures and graph search. Since the assignment gives you a lot of freedom to develop your own approach to the problem, readability of your program will be very important. Please make sure to adhere to the principles of structured programming and use good commenting.

The assignment is due on Monday 31 July at 5pm. Before you start programming, pay heed to the following advice from the Tao of Programming (Book 3):

Thus spake the Master Programmer:
"When a program is being tested, it is too late to make design changes."

Have fun,
Michael

Web server up and running again

Posted by Michael Thielscher Wednesday 05 July 2023, 11:43:14 AM.

The web server for the lecture slides & problem sets, which was down for a few hours this morning, is back, so that you can now access all the material including the sample solutions for last week's problem set through WebCMS again.

Let me take this opportunity to remind you of the mid-session test later today, starting at 6:30pm . For easy access, here is a direct link to the test on Moodle:

Mid-Session Test - Wednesday July 5

Problem Set 5, Exercise 5

Posted by Michael Thielscher Friday 30 June 2023, 10:07:02 AM.

Exercise 5 was missing a precise instruction of how to print the edges in the resulting MST. As a consequence, your output may not have matched the dryrun format even though your tree is perfectly correct.

For this reason we have simplified the specification to only asking you to output the sum of the edge weights in the resulting minimum spanning tree.

If you have already tested and submitted a solution to Exercise 5, please adjust your program accordingly and resubmit. Please note also that the exercise requires the use of the given Set ADT and the WGraph ADT from the lecture to implement Prim's algorithm.

In-person help lab on Thursdays

Posted by Michael Thielscher Thursday 22 June 2023, 05:14:49 PM.

Just a reminder that the in-person help lab on Thursdays has been moved to the Piano CSE Computer Lab (room LG18 in building K14 ).

Week 1 submission results

Posted by Michael Thielscher Friday 09 June 2023, 11:20:22 AM.

If you have made a test submission for week 1, then you can now collect your marked submission from WebCMS3 (→ Collect Submission), or from a CSE computer using the command

classrun -collect week1

You will see what test cases were used and how your program handled these.

Keep in mind that this was just a "mock" assessment and does not count towards your mark for the weekly assessment component.

Some common errors that I noticed, and hints on how to avoid them:

• Programs did not compile without error when the options -Wall -Werror were used. A common error was, "unused variable". It is generally considered bad programming practice to declare variables that are not used. The auto-tester is very strict in that it refuses to compile programs with even a single warning like this or any other.
  Solution: Always ensure that your programs compile on a CSE machine with all the options -Wall -Werror -std=c11 as required. A good way to check this is dryrun .
• Programs failed to compile because of an incorrect use of header/implementation files. If your program includes a line of the form #include " filename. c " , then this is probably wrong. Only header files should be loaded into a client program. A good way to check this is dryrun .
• If you did submit but cannot find your marked assignment, then this means that your submission was empty, that is, you submitted empty files or no files at all. I recommend to always double check that all the files you want to submit have been successfully submitted, and that they are not empty (i.e. the file size is > 0).

Checking your submissions

Posted by Michael Thielscher Tuesday 06 June 2023, 10:06:51 AM.

It is always a good idea to check whether your files have been submitted correctly. You can do so on WebCMS by clicking on the problem set under Upcoming Due Dates (top right), then click on "Check Submission" here:

Ensure that all the files you intended to submit are shown and that none of these files are empty (= 0 bytes).

Help Labs

Posted by Michael Thielscher Thursday 01 June 2023, 02:18:32 PM.

A reminder that if you need help with

• setting yourself up to develop, compile and run C programs;
• debugging your solutions to the programming exercises from the current problem set;
• testing your programs with dryrun and submitting them via give

then please drop into one (or more) of the weekly help labs, either

• in person every Thursday, starting today: Quad 1042 – bring your own laptop, or borrow one from the station on the ground floor at K17; or
• online on Fridays 3pm-4pm through the link to "OnLine Help Sessions" on Moodle ; or
• online on Mondays 12noon-1pm through the link to "OnLine Help Sessions" on Moodle

to meet one of our friendly lab demonstrators who are happy to assist and answer any questions you may have.

Lecture on Wednesday, 31 May

Posted by Michael Thielscher Wednesday 31 May 2023, 02:36:06 PM.

A quick note to let everyone know that tonight's lecture will happen despite the university-wide strike.

Welcome to COMP9024: Data Structures and Algorithms

Posted by Michael Thielscher Thursday 25 May 2023, 02:05:44 PM.

Dear COMP9024 Student,

Welcome to this year's course.

This is a reminder that our course will begin next week on Tuesday (30 May) from 6-8pm in Ainsworth G03 (Building K-J17).

Meanwhile check out the course webpage webcms3.cse.unsw.edu.au/COMP9024/23T2/ . Have a look at the "Course Outline" to learn more about the contents of the course, the assessments and recommended textbooks.

See you on Tuesday,
Michael