CS106B: Programming Abstractions

Announcements

December 15^th, 2012

Congratulation on making through autumn quarter and for emerging victorious!

The final exams have been graded, and will be available for pickup once school is back in session. I've posted the answer key right here so you can inspect my answers and get the skinny on how the class did as a whole.

You should received feedback on all of your assignments by Sunday evening at midnight. I'll be computing final grades on Tuesday, and promise to post them by Tuesday evening.

Enjoy the holiday vacation, and I'll see a bunch of you in CS107 next quarter. Woohoo!

December 5^th, 2012

Apologies for the delay! Here are the notes from Monday's overview session for Pathfinder. Let Jerry or me know if you have any questions! - Dawson

December 1^st, 2012

Happy weekend, everyone.
A student who'd already read through the Assignment 7 handout pointed out a reference to a section problem that I didn't use in CS106B this quarter. The problem is a good one, however, because it provides a small example that leverages the functionality of the TokenScanner class. You need to use the TokenScanner class from the CS106 library set for Assignment 7, so I want you to have access to the problem, the starter files (it was a lab problem), and my solution. I've bundled all of these materials into a little zip file for you and placed it right here.

Also, note that I'm currently working on arranging an Assignment 7 Overview Session for this coming Monday. I'll send out a formal announcement over the course of the weekend once I've secured someone to teach it. :)

Thanks, stay dry, and have a great weekend.

November 25^th, 2012

Hi everyone. I hope you all had a great break! I had a few students ask me to upload the slides I used last Friday for the optional lecture (about STL iterators and algorithms). I've annotated the slides, which you can access here. Feel free to email me if you have any questions! -Dawson

November 16^th, 2012

Hey there, everyone. Sophia Westwood taught this past Wednesday's assignment overview session, and she and Will Monroe put together a terrific handout summarizing everything she covered. Download it at your convenience.

November 8^th, 2012

Brett Wines taught the Assignment 5 Overview session yesterday, and he typed up these notes for those of you who weren't able to make it.

November 6^th, 2012

There is a remnant comment in Assignment 5's pqueue.h file that mentions we extract the lowest priority element instead of the highest one. Ignore that. The goal of the data structure is to order strings behind the scenes just enough so that extractMin returns the alphabetically smallest string currently being stored.

We'll be holding an Assignment 5 overview session tomorrow, from 4:15 until 5:05 p.m. in 420-040. So, if you're hankering for some info on how to get started on the PQueue assignment, then stick around after lecture. For those who can't stay, we'll provide a one-page-or-so summary of what gets said so you can at least get the same information.

I need to move my office hours tomorrow (Wednesday). I normally hold office hours from 10:15 a.m. until noon, but I have an unmovable meeting at 10:30 a.m. for about 45 minutes. I'm going to shift my office hours forward 1:15 until 2:45 p.m. tomorrow, just this week. I also need to truncate my Friday hours to end at 11:30 a.m., as I have a meeting in San Jose at 12:30 p.m. (Sorry, it's one of those weeks where I need to leave my office more than I'm used to.)

Also, if you know you're planning to take CS107 next quarter, I humbly request that you sign up via Axess as soon as you can. We're trying to allocate TA's for next quarter, and our initial TA allocations are based on a combination of last year's numbers and the current enrollment figures. An instructor's worst nightmare is not having enough staff to support the students, so please make sure we get the staff we need by letting us know if you'll be part of the class. (I'm not trying to game the system or anything, as I'll eventually get the right number of TAs. I just don't want to scramble over Christmas break to try and find TA's after everyone's already been assigned. Doing that is the opposite of fun.)

November 5^th, 2012

Hey there, CS106B rock stars. The midterms have been graded, and two thirds of you pull a 90 percent or better. In my 16 years of teaching here, I've never had such a high midterm average in any CS106 course. Truth be told, I recognize the exam was on the easier side, but it wasn't that easy, so the majority of you should be very, very happy with yourself for mastering the CS106B material we've covered thus far.

We'll be giving the exams back after lecture today. All exams not retrieved today will be available for pickup from Jerry's Gates 192 office during his office hours. If you want to check out the midterm solution, go right ahead.

Great job, everyone. I'm very happy for all of you.

October 24^th, 2012

Today, I'll be finishing up algorithm analysis and Chapter 10 to the extent I feel I need to cover it before moving on. You'll be getting a short assignment this Friday—in my opinion the least intense of the quarter—to help ground you in all things sorting and algorithm analysis. In addition to reading through Chapter 10, you download Keith Schwarz's awesome lecture slides, which I cannibalized for the purposes of my own lecture. You'll need to download an open-source, free-of-charge software product called Open Office in order to view them, but it's a relatively painless download, and you'll be happy you can more patiently step through the slides and the animations.

Note that I've posted a practice exam and a companion solution set. The real exam is next Tuesday evening, and the practice exam contains a bunch of problems I've given on exams in the past. The practice exam is really about 75% longer than the exam I expect to give you, but I wanted to give you as many additional practice problems as possible. The exam covers all things recursion, recursive backtracking, and memoization, but it does not cover algorithm analysis, searching, or sorting.

Thanks, and see you all in a few minutes.

October 23^rd, 2012

One of your fellow CS106B students surfaced a collection of YouTube videos that mix Hungarian folk dance and sorting algorithms. The videos are absolutely brilliant—at least in concept if not execution—and are worth 10 minutes of your time. Check them out right here.

The mergesort and quicksort dances are inspired. They make me want to give up lecturing and take up algorithmic choreography.

October 20^th, 2012

Students working on Assignment 3's Boggle assignment on the PC may have run into issues with fonts. A new starter project has been uploaded with a fix in place. You can manually fix the issue by going into gboggle.cpp and replacing all appearances of the font "Helvetica" with the font "Arial".

October 18^th, 2012

Will Monroe led yesterday's Assignment 3 Overview session, and typed up these notes for those who couldn't make it (and even those who could.) Go ahead and read through them if you're concerned about getting started on Assignment 3 and needs some pointers.

October 11^th, 2012

Keith Schwarz uncovered an interesting video illustrating a continuous version of the Game of Life. It relies on a related set of rules, but with floating point instead of integer values. Check out the video right here.

October 11^th, 2012

Hey there, CS106Bers. A few students have come up with their own grammar files (one to generate mock news articles, another to generate Presidential candidate speeches, and a third to generate NYC subway directions, courtesy of Robbie Ostrow, Steven Vogel, and Matthais Nehlson). You can grab them and drop each of them into your grammars folder to play with them if you'd like. You can get the new grammar files by clicking right here.

Enjoy! And see everyone tomorrow at the crack of 3:15 p.m.

October 10^th, 2012

A student pointed out that the bond.g grammar file doesn't include a final blank line like it should. Most implementations won't cough on it, but if you're doing aggresstive error checking, the formatting issue might mess things up. The best thing to do is to just go in and manually add the one final blank line yourself, since it's too minor a concern to recommend a fresh download of the entire starter project again.

Each quarter I distribute a small number of optional programming problems, and I'm just this second posting the first one right here! The problem takes the form of a contest, where I accept solutions from everyone, but reward the first three of you to submit efficient, working solutions with dinner out and about in Palo Alto at some point later in the quarter. The entire problem statement should be clear from the document itself. The primary difference between the optional contest problem and the regular assignment questions is that you must solve these all by yourself without the help of any other people.

This is a problem I wrote for the Regional ACM Programming Contest three years ago, and it was reasonably challenging but not impossible, and a good number of the top teams submitted working solutions. That means that many of you are more than outfitted to tackle this, knowing you have a good amount of time to submit something.

Good luck! [I'll be distributing another problem like this--one requiring recursion and caching--in about a week, so if you don't like this problem, then don't worry, because there are more to come.]

September 29^th, 2012

Will Monroe taught yesterday's Assignment 1 overview session, and was nice enough to type up these notes for those who wanted to come but couldn't.

Big thanks to Will for pulling together the overview session on such short notice.

September 26^th, 2012

Hey there, CS106Bers. Announcement time!

Your first assignment goes out today, and is formally due a week from Friday. The assignment is best tackled in short bursts, and because we want you to start early and work patiently and thoughtfully over the course of the 9 days you have, we're encouraging (though not actually requiring) you to submit a partial solution a week from today. Note that the assignment is due at 3:00 p.m., so that you have a good 15 minutes to make your way over to the awesomeness that is CS106B lecture at 3:15 p.m.

Finally, if you have the energy and the interest, check out this little flyer. Stanford is holding a little programming contest this Saturday, and while the actual purpose is to select the teams we send to a regional programming contest, the local contest itself is fun, and you get to meet a lot of fellow CS enthusiasts who enjoy a nerdy programming problem or two (or ten). If you have any questions about the contest this Saturday, then by all means get in touch with me.

September 6^th, 2012

Welcome to CS106B, everyone! I'm looking forward to an awesome quarter of coding together. I have lots of new ideas on how to upgrade the syllabus and the manner in which we all get things done.

Class begins on Monday, September 24^th and meets at 3:15 p.m. in 420-040 every Monday, Wednesday, and Friday.

Everyone needs to visit http://cs198.stanford.edu/section sometime between Thursday, September 27^th at 5:00 p.m. and Sunday, September 30^th at 5:00 p.m. to state which discussion section times work best. Come Sunday evening, we'll distribute everyone across the discussion section times as optimally as possible and email everyone his or her section assignment. For those familiar with our CS106A course, note that our discussion section format is different, and that attendance is required. As opposed to CS106A discussion sections, where most if not all code is written by the section leader on the whiteboard or blackboard, our discussion sections are a mix of traditional recitation and laboratory.

CS106B Resources

Handouts

Assignments