Friday, November 23, 2007

Chess Fixes

It has come to our attention that there were a few minor errors in and I have fixed them and and updated the stubs, which you can use to update your code as desired. Also, I fixed up the section on the timers, which was a bit out of date. Sorry if this caused major confusion. Also, if you have questions about anything in the assignment, please check the bboard--Owen and I have been making an effort to clarify things there if they are asked.

Tuesday, November 20, 2007

Office Hours

My office hours tomorrow will be in WeH 3406 on the off chance that anyone wants to come for them.

No Office Hours Tuesday, Friday

Anthony will not be holding office hours this Tuesday due to the holiday. Also, my Friday office hours are canceled for the same reason. Happy Thanksgiving!

11/27 Anthony Office Hour canceled

Anthony's office hour tuesday (11/27) will be canceled due to break.

Monday, November 19, 2007

Quiz 4

Quiz 4 will be given during recitation next week (28th Nov). Don't forget to review your material for it! Happy holidays!

Saturday, November 17, 2007

Chess Server Account Signup

The chess server account sign-up page is now up and running. You will need to enter your andrew id, a handle for your chess server account, and a password for your chess server account. This password should not be the password you use for anything else. Your server handle will be shown when you play games, on the ranking site (yet to be activated), and when people see who is online. You should receive a confirmation email (on andrew) after your account has been created. If you have any problems with account creation, email me or Will.

Wednesday, November 14, 2007

Chess Fixed

The chess assignment should now be completely fixed. If you have any problems with FrontDesk, please email me. I made significant revisions to the assignment from last semester and obviously my testing was not sufficient the first time around. If you already started the assignment you may want to download the stubs again. Sorry for the inconvenience. Hope you have fun completely destroying the bot I wrote when taking the course as revenge!

The State of Chess

I incorrectly deployed the chess assignment to FrontDesk. We are working to correct the problem, and it will be fixed tonight. I will make another post to the portal when everything is fixed. There will be no changes to the code you need to implement (some files just need to get moved around and compiled correctly).

Exam Correction

For the compression question part c) on the exam: "For a given input, X = x1, x2, x3, ...xn, there is exactly one Huffman tree which will produce a maximal compression ratio." The official answer we graded by was "sometimes" The one instance where there is exactly one tree for the maximum compression ratio is for an empty file (only 1 such tree exists). Since we wrote "x1, x2, x3, ...xn", it is not clear that the length of the file could be 0. So if you wrote "sometimes" or "never" you should receive full credit. If you need a score correction for THIS part of the question, please contact YOUR TA for a score change.

Monday, November 12, 2007

Office Hours Pushed Back

Sorry I forgot to post this earlier, but I needed to change my office hours today and hold them from 6pm - 7pm. Sorry for the late notice!

Friday, November 09, 2007

Midterm 2 Grades Released

We have released the grades for the second midterm on FrontDesk. Both the mean and median on this exam were 64.5% (with a standard deviation of 14.0%). You can pick up your exam from Prof. Scherlis's office starting Monday. We will be devoting a portion of next recitation to going over the midterm, so pick it up before going for your recitation.

Wednesday, November 07, 2007

Additional DP and Code Analysis Questions

At the review session students requested additional practice problems on Code Analysis and Dynamic Programming. So here they are: Questions: Solutions: If you have not done so already, check out the practice midterm and the recitation material from today. Both of these have more problems on Code Analysis and DP. You can access the recitation material from the "Lectures" tab on the portal.

Recitation 9: DFA / DP

Handout: Solutions: Slides:

Compression Theory Solutions

Since your compression lab will not be graded and returned until after the midterm, here is a temporary link to the theory question solutions:

Saturday, November 03, 2007

Recitation 8: Dynamic Programming

Slides: PDF:

Suggested schedule

We have found that a small but significant number of students are having trouble meeting the deadline for the assignments, so we sat down and figured out a suggested timeline for doing the project. If you are very much behind the schedule we propose, we feel that you might run out of time towards the deadline.
  • General Graph - done by the weekend
  • Union-Find - done by Wednesday
  • Dijkstra - done by Friday evening/Saturday morning
  • Kruskal - done by Monday
  • Theory + last-minute fixups, additional comments, etc - done before the deadline on Tuesday
Good luck with the assignment!

Friday, November 02, 2007

Midterm Review

The midterm review will be on Wednesday, Nov 7, 6:30-8pm in Wean 7500. Please pose questions to the discussion board in advance of the review so that the TAs know what to cover.

Partner assignments

There were a number of people who wanted partners for the last assignment, but couldn't find one. If you do not have a partner for the current assignment, and would like one, please post a request on the discussion board. Be sure that you work together; do not simply split up the work. Also, whenever you find that you are having trouble with an assignment you should talk to one of the TAs or the professors about it immediately. There is little we can do if you come to us the day an assignment is due.

Thursday, November 01, 2007

Exam Nov 8

The second midterm will be on Nov 8th. It is in-class and cumulative. Do not bring cell phones, PDAs, computers, or any other such device. Bring your student ID. You may bring a single 8.5"x11" page of notes (both sides). We will be announcing a review session shortly. Please check the portal for the announcement. We will also post an exam from a previous semester so that you have a sense of what to expect. Here is a sample midterm and its solution set.

Lecture 20: Dynamic Programming 2

Lecture 20, Dynamic Programming 2