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[MUSIC PLAYING] [MUSIC ARMIN VAN BUUREN, "THIS IS WHAT  IT FEELS LIKE"] 

[MUSIC - M4SONIC, "WEAPON 2.0"] 

[CLAPPING] 

STEVE BALLMER: Woo! This is CS50. 

[APPLAUSE] 

DAVID MALAN: This is CS50. And this is the start, and end, of Week 12 for the very last time. You'll recall from Week 0 that we promised this, that what ultimately matters in this course is not so much where you end up relative to your classmates, but where you, in Week 12, end up relative to yourself in Week 0. 

Well, we are here now in Week 12, and you might look back fondly, or remarkadly, at just how far you've come when this was the worst of your problems, some weeks ago. But consider how far you've come since then. Particularly, if among those with no prior experience, just weeks later, were you implementing a fairly sophisticated data structure like this hash table here, or even this TRI here. 

Just a few weeks later, and just a week ago, were you implementing this, a mash-up of multiple APIs uisng asynchronus JavaScript calls and HTTP requests behind the scene. Ultimately, creating an entire web app from something that began with just a few hash marks. Now, indeed you might recall that 78% of you had no prior experience, and we proposed that you might be feeling a little lonely at the beginning, but realize that you are now very much among friends and supporters here. 

Now, it's a tradition in CS50 to not only start the semester, but also end the semester with a bit of cake. Indeed the team has been downstairs cutting it up, and sampling the cake, but that awaits in just a little bit of time. But I thought I'd pick up where we left off and get some closure today. 

You may recall this here website, I thought the only good thing I could do is write these kind folks upon having endorsed them so in class just a couple of weeks ago. And I will say to their credit, I got back this reply from ediblearrangments.com. Good morning, Mr. Malan. We have inquired with our IT department regarding your concern. They advise that as of next week, there will be a website patch applied. We appreciate the feedback. And indeed-- 

[APPLAUSE] DAVID MALAN: And indeed if you go to editablearrangments.com now, click login, you are indeed sent to the HTTPS version of the site. 

[APPLAUSE] 

So there you have it, CS50 here making a difference, one website at a time. So now, the final project is, of course, all that awaits now. And realize that there's any number of ingredients that you can weave into this project of yours. 

Indeed what many students do, if tackling a web based final project, will take p set 7's distribution code, CS50 Finance, and then will rip out parts of it that are of interest, or germane to their final project, like the look up function, which is surely very specific to Yahoo Finance. And they'll add in their own code, and build atop the login mechanism that we provide you with. And so that is absolutely a great place to get started. 

Especially if over break, and shortly thereafter, you're just not really sure where to begin to create something that hasn't already been handed to you at least in part. p set 8.2, if you want to do something with AJAX, or you want to write a script that imports a really big data set into a database, use p set 8 as a model in which you can build your own code, ultimately. But realize, too, that there's even fancier ways to get started. 

A very popular framework, that we're fans of, is called Laravel. This is a PHP framework that essentially adds to PHP a number of features that are already commonplace in the world of Ruby and Python, other programming languages that have built into them, or on top of them, additional frameworks. And so Laravel will take p set 7's framework, essentially, and give you a whole lot more tools for your tool kit. So if curious, and if you'd like to not only apply lessons learned, but tackle some new lessons for your final project, check out this and similar types of frameworks online. 

How about hosting your website? You can certainly put your final project, if doing something web based, on your CS50 appliance, and most students do. But if you'd like to actually take the worldwide web out for a spin and put your code out there, realize that it's pretty straightforward these days to buy a domain name for a few dollars, to set up your domain name's DNS settings for the IP address stuff. And then actually push your code to some remote server so that someone can visit you at something.com, or whatever domain name you happen to buy. 

Stay tuned to CS50's home page in the days to come, where we'll post some instructions for doing exactly that. If you'd like to follow some guidance, or if you'd like to venture out on your own, there's so many popular frameworks and systems out there. Many of which are free, or super cheap, or at least free for students. AWS, or Amazon Web Services, is one. In fact, that's where CS50 runs most of its own servers in the so-called cloud, using virtual machines, servers that aren't really physical. 

They're the illusion of physical servers, but that we, and you, could have complete control over. And we just had a seminar, in fact, a couple weeks ago on that. Parse.com is a super popular back-end tool that you can use to actually host a database. If you don't want to figure out, or stand up your own MySQL database, there's this and other related services that let you focus on the part of your app that you really like, the front-end or the user interface, or the features, and then outsource to someone else, often for free. Certainly for student scale prototypes, any back-end services like email or databases that you might need. 

Now, for authentication, a super common FAQ in CS50 is, how do you authenticate users? Not with their own user names and passwords, but with like Harvard IDs and PINS. Well, realize CS50 has a service called CS50 ID, via which you can do exactly that. And then those of you tackling, say, mobile projects, where you're kind of conflicted if you want to do an iPhone app, a Windows Phone app, an Android app, or any number of other devices out there, realize that there are actually tools that allow you to write your app, in typically JavaScript, or some similar language. And then deploy it to multiple platforms like iOS and Android and the like, phonegap being one, Titanium another. 

So if you're sort of conflicted, and realize that there's a bit of a learning curve to learning just one of these languages, realize you can take your own new found familiarity with JavaScript out for a spin, and apply it there. And there's so much more that you can find on your own, or by consulting your TFs. Now, what about life after CS50? Just so that this is said, at least once, you're not going to be handed problem set specifications and distribution code in perpetuity, but realize that you don't need the CS50 appliance to continue coding on Mac OS. 

It's a wonderful, useful environment in that it's pre-configured to be representative of a nice Linux system. But you can certainly use any number of freely available tools these days to write code on your own Mac without the overhead of an appliance, or on your own Windows computer, or if you're running Linux, a number of tools exist there as well. So that's just a whirlwind tour that you might want to curl up with at some point. But for now, let's take a look ahead and what remains. 

In particular among the course's historical events is the CS50 hackathon. An epic all nighter, at which you'll arrive around 7:00 PM, set up shop with your laptop, and project, and friends. And dive into final projects in an environment that looks a little like this upon arrival. You'll check in here, you'll then get down to work, you'll help out a classmate. 

You'll indulge in first dinner around 9:00 PM, second dinner around 1:00 AM. And then for those still standing at the end of the night, we'll take you to IHOP. But along the way there will be a photo booth, not like this, and indeed actual CS50 shuttles on our way to IHOP. 

Now, the CS50 fair, for students in the class, this is your opportunity to exhibit proudly your final projects. Not only to others, but typically 2,000 plus attendees from across campus, students, faculty, folks who see the balloons along Oxford Street and come on in. So realize that what awaits there are glimpses of maybe each other's projects here, where you'll bring your laptop. We'll set up tall tables on which you put your laptop, hop on the Wi-Fi, and demo your projects to passers by. 

Meanwhile, there will be music, and popcorn, and candy, and more. So that you'll have ample opportunities to mingle. We'll have friends of ours from industry, recruiters from any number of these companies here there just to chat up students about life after college, or internships during college, and the like. You'll see, too, that there's a raffle to incentivize not only you to strike up these chats with friends, but also to invite your own friends, or convince your own friends to come see your project. 

You can sweeten the deal by these little cards that will be handed out. Each of them will have placeholders for little Smiley face stickers. You guys as the students will be given Smiley face stickers. And for anyone who ventures up to you and says, hey, what did you do? Or asks you for a demo of your project, you hand them a sticker. They put it on their card. And that qualifies them for any number of fabulous prizes, including those pictured here, which are then raffled off at the end of the event. That's it for CS50. And along the way, there will be ample popcorn, and stress balls, and candy, and even last year the Harvard band, who was not expected, but was in attendance. 

There will be a photo booth there as well, and massive numbers of balloons like these ones here. So many so, that invariably the staff try to pull this trick at the end of the night, never quite works. But for you, if you'd like to invite your friends to this event-- 

SAM CLARK: Now, as we come over to the next stop on the tour. You'll notice a distinct-- 

[LAUGHTER] 

File on in. You'll notice a distinct departure from the Gothic architecture that we saw on the rest of the tour of Yale's campus. Now, here we are at Sanders Theater. Sanders Theater is really a cultural and academic hub here at Harvard. Commencement was held here until 1922. It's modeled after the Sheldonian Theater in Oxford, England, as a matter of fact. And it serves as a location for many cultural events, and big academic events here. 

Many A cappella groups perform in Sanders, the Crocodillos perform here frequently, they're sort of like the Wippenpoofs 2.0, almost. As well as the largest class actually at Harvard, CS50, is taught here. Who on the tour is interested in computer science? Anyone interested? Terrific. Well, if you happen to matriculate at Yale, you'll really, really want to be taking CS50. 

[LAUGHTER] 

[APPLAUSE] 

You won't actually be able to take it physically within Sanders Theater, however, CS50 will be live streamed over to you in New Haven. As well as you'll have an entire support staff, support network of staff there to take CS50, to learn all about computer science. So this is Sanders Theater. It's not Gothic, but it's great. Does anyone have any questions before we move on to the next stop? Yeah. 

AUDIENCE: Is that David Malan? 

[LAUGHTER] 

SAM CLARK: Oh, my God it is! Let's take a selfie. Selfie! Take a selfie! Right here, right here. Here, someone hold it up. Someone hold it up. How are you, David? 

DAVID MALAN: Hello, DA 

SAM CLARK: I'm doing well. I got to flip it around. And duck face, David. 

[LAUGHTER] 

Yeah, he likes that. Terrific. Terrific. Well, we'll move on to the next stop. Our next stop is the Harvard stadium, where we've had great luck in the last 13 years. 

[LAUGHTER] 

[APPLAUSE] 

DAVID MALAN: So the rumors are indeed true. For the first time in history, students at Harvard and Yale alike will be able to take a course called CS50 this coming Fall in 2015. We will put asie the rivalry for nearly 100 years, and ultimately, in Fall 2015, actual Yale students will be able to take CS50 for the first time. The lectures will indeed be streamed from here, your successors in this audience, to New Haven, where students will be able to engage in person, or as some of you have so optimized, online live, or on demand after. 

But we will be standing up a local support structure, complete with teaching fellows, course assistants will be leading sections, and office hours. CS50 Puzzle Day will be held in Cambridge, and we will invite our Yale friends to Cambridge for CS50 Puzzle Day, as well as the CS50 hackathon. And then at semester's end, there will be an epic display in both Cambridge and in New Haven of CS50 students from Harvard, and Yale alike on display in those respective towns. 

And indeed if you have any friends who go to Yale, we do need some TFs and CSs so do send them to this URL here. But we will in the meantime, be sending one of CS50's own best teaching fellows, Jason Hirschhorn, who's about to graduate, having just finished his thesis on the intersection of computer science and education. Jason will be working full time at Yale, and will be on the ground there helping us to stand this up and bring these two universities together via CS50. 

[APPLAUSE] 

Now, along with CS50's production team, I had an opportunity to hop in the car with this guy and take a look at what awaits us in New Haven. 

[VIDEO PLAYBACK] 

[MUSIC - "MOVIN' RIGHT ALONG"] 

-Movin' right along in search of good times and good news with good friends who can't lose. 

-This could become a habit. 

-Opportunity knocks once let's reach out and grab it. 

-Yeah! 

-Together we'll nab it. 

-We'll hitchhike, bus, or yellow cab it. 

-Cab it? 

-Movin' right along, footloose and fancy free. 

-Getting there is half the fun come share it with me. 

-Movin' right along. 

-We'll learn to share the load. 

-We don't need a map to keep this show on the road. 

-Hey, Fozzy, I want you to turn left if you come to a fork in the road. 

-Yes, Sir. Turn left at the fork in the road. Kermit? 

-I don't believe that. Movin' right along, we've found a life on the highway. 

-And your way is my way. 

-So trust my navigation. 

-Movie stars with flashy cars, and life with the top down. 

-We're storming the big town. -Yeah. Storm is right. Should it be snowing? 

-No, I don't think so. 

-Movin' right along. 

-Footloose and fancy free. 

-Be ready for the big time 

-Is it ready for me? 

-Movin' right along. Movin' right along. Movin' right along. Movin' right along. -Maybe you better pull over. -Yes, Sir. Oh, look at that. 

[END PLAYBACK] 

DAVID MALAN: We'll see Yale in 2015. 

[APPLAUSE] 

So now some thank yous. Suffice it to say there's an entire family, both in front of and behind the camera, in this class that makes everything work ultimately. And I'd like to acknowledge a few, and then the entire staff by way first of Colton, whose EDM has permeated the start of lectures for some number of weeks now. As well as the entire production team, who's been making everything look so beautiful this year. Dan in Chile, and Andrew, and Cheng, and Colton, and Ramon, and Barry in back, and Kenny and everyone who's been involved behind these cameras, making everything possible. To Gabriel, as well, our head teaching fellow. 

[APPLAUSE] 

If you didn't already know, Gabriel actually found CS50 by way of the production team's videos. Indeed growing up in Brazil a few years back, he discovered that all of CS50's material was online, and he dropped me a kind note asking if he might be able to translate it to Portuguese for his classmates. And indeed he did, ultimately, lecturing to some 50 students, his classmates, in high school. Followed by 150 students the next year, and wonderfully his dad was in fact filming the whole thing so you can find Gabe's lectures of CS50 in Brazil online as well. 

And now Davon here, Davon here has been running the course, and has been making everything run so smoothly, and without him we could not manage the team that we now have. And then of course, Rob Bowden. 

[APPLAUSE] 

Rob's now been with the course some five years, having approached me sophomore year with an interest in getting involved in the class. And then became assistant head TF, and then Head TF, and then Preceptor. And now, believe it or not, the very distinguished role of Member of Technical Staff, which in the computer world actually carries with it some weight. And so that understatement is actually meant to be of the highest regard to Rob. 

Allison, of course, who's been leading our official sections on camera once a week, and making sure there's a resource available online for students who are unable to tune-in in person. And then, of course, a TF, who I think has been at every single office hours this year, including these here, these here, those here as well. And indeed [? Zamila, ?] who has walked everyone through the course's problem sets, and without whom, we could not expect, I dare say, so much. 

And then lastly, Cheng here, who is known for much more than these elephants, which have been appearing at most every lecture. Indeed Cheng recently got together with CS50's production team to put together this thank you for the entire team, by way of a little segment we call, Cheng On The Street. 

[VIDEO PLAYBACK] 

[MUSIC PLAYING] 

-This is Cheng with Cheng on the Street. And today, I'm here at CS50's Quiz One Grading Party, where the staff members of CS50 have gathered to grade quiz one. I wouldn't really consider it a party, but you get the idea. I'll be asking them some questions about their experiences this semester, and maybe a few technical questions, then we'll solve them. 

-I don't think I'm ready for this. 

-It's OK. 

-OK. -How many bits are in a byte? 

-4, 8. 

-What does PHP stand for? 

-PHP? Hypertext protocol. 

-Is it a protocol, though? -I don't know. Is it? 

-Eh, eh. Buzzer. 

-I know that P stands for PHP. 

-So where does it stop? 

-It never stops. 

-It has to stop at somewhere. -No, it doesn't. -Acronyms simplify to a word. -No, mm-mm. [? Recouragin? ?] -This is a serious question. [LAUGHTER] What comes next in this sequence of numbers? 2, 4, 8, 16, 32, 955. 

-I thought you were going to say 64, but OK. -What's the next number in the sequence? -CS50. -That's not even a number. -I have no clue. -None of you are right. Please, go back to grading. What's 2 to the power of 64? -Oh, jeez. I should know this. 

-I don't know. -OK. 

[LAUGHTER] 

-How many stress balls does it take to fill Sanders Theater? 

-Too many. 

-You can never have too many stress balls. 

-Am I right? What's the correct answer? -There is no correct answer. -I'm sure there is. -It depends on the size of the stress ball. Do you know who Rob Bowden is? 

-Yes. He has better hair this year than he did previous years. So it was a little difficult recognizing him, but I managed it. 

-Is he the buff guy? 

-Yeah. -OK. Yeah, I like him. 

-Now that you mention that, I have a question for you. 

-All right. 

-What's Rob Bowden's bench press? 

-IT max. 

-What is his max bench press? -You. 

-Thank you so much to CS50's TFs, CAs, producers, designers, researchers, and everyone else who's been involved both in front of and behind the camera here in CS50. We surely could not do this without you, and we cannot wait to welcome new members to the staff. -Everyone at this table, can we get a hug? 

-Thank you. 

-Thank you very much, staff. Thank you for becoming staff. This concludes our interview. Thank you for being on staff this year. 

-Thank you so much. 

-Thank you. 

-No, no, thank you. 

-Did I do a good job or what? 

-You did wonderfully. This was Cheng, with Cheng on the Street, and this was CS50 2014. 

-What did we talk about? We just had this conversation. This is not a toy. 

[MUSIC PLAYING] 

[END PLAYBACK] 

[APPLAUSE] 

DAVID MALAN: So CS50 is indeed now recruiting for TFs, course assistants, producers, designers, and any number of other roles that enable this to go on behind the scenes. And now, for something a little special. As you know, Colton has introduced his EDM to the class, but today he got the band together and CS50, before we bring some students up on stage, I give you Colton, Gabe, and Taylor. 

[MUSIC PLAYING] 

COLTON: Feel my way through the darkness. Guided by a beating heart. I can't tell where the journey will end. But I know where to start. 

Try to tell me I'm too young to understand. Say I'm caught up in a dream. Life will pass me by if I don't open up my eyes. That's fine by me. 

So wake me up when it's all over. When I'm wiser and I'm older. All this time I was finding myself and I didn't know I was lost. So wake me up when it's all over. When I'm wiser and I'm older. All this time I was finding myself and I didn't know I was lost. 

I tried carrying the weight of the world. But I only got two hands. Hope I get the chance to travel the world. I don't have any plans. Wish that I could stay forever this young. Not afraid to close my eyes. Life's a game made for everyone and love is a prize. 

So wake me up when it's all over. When I'm wiser and I'm older. All this time I was finding myself and I didn't know I was lost. Everybody! So wake me up when it's all over. When I'm wiser and I'm older. All this time I was finding myself and I didn't know I was lost. Didn't know I was lost. Didn't know I was lost. 

[APPLAUSE] 

DAVID MALAN: Coming this year to the CS50 Fair, live music as well. So now, our last opportunity for a bit of audience participation. For this we need six students and three staff. Let's see here, OK, you're practically jumping out of your chair. Come on up. 

OK. How about you two together over here, come on up. And how about you two and you one, come on up. Let's grow the teams a bit. OK. Right there. Come on. Yeah. You, come on down. That's going to be hard. 

OK. OK. Fine, come on down. See you in a few minutes. All right, so come on over here. We're going to get two more chairs and let's do Nick, and Alison, and this Yale student over here, and Rob Bowden, come on up. Meanwhile, if Cheng could join me on stage. 

If you guys would like to form two student teams, and one staff team. And Cheng, if you could distribute these chairs here, I'll get the board ready. This is incredibly awkward. OK. Make your way to a chair there. 

Come on over. Come on down. And I think the Yale student will be playing for the staff team. Excellent. We should have enough chairs, hopefully. If not, we'll grab another. Where do we need it? Over here, come on over. All right. 

CHENG GONG: Do we need more staff? 

DAVID MALAN: No, no. It's going to be two student teams and one Harvard/Yale staff team. All right, so we do have this tradition of playing Jeopardy, or really, our own version of Jeopardy where we just ask questions and expect answers. But the questions we're going to ask were not written by us, they were written by you. You may recall a rather long form for Problem Set A. 

[LAUGHTER] 

I have to admit, most of them didn't make it into quiz one. We got maybe 500 questions asking, what is HTML? What is HTTP? What is CSS? So they weren't exactly the most challenging of questions, but we went through hundreds and hundreds of questions to sample the following. 

So Cheng here has kindly offered to run the board. We'll go ahead here and call this Team One, Team Two, and Team Three. And let's say that Team Three has won the toss, so you guys are going to glance to your left or above you, pick a week, and pick a dollar amount. 

We will then ask the question, and Cheng will award you, or deduct from you the requisite points. Team Three, what would you like? I'm hearing a lot of Week 0 here. 

[LAUGHTER] STUDENT 1: Can we pick any? DAVID MALAN: Any category, any amount. STUDENT 2: Week 0, 500. DAVID MALAN: You're putting more thought into choosing the question than I wrote into selecting them All right, so what did you say? OK. And then the first hand that goes up will be considered the one who has buzzed in. What is the difference between global and local variables? I saw Team Two. STUDENT 3: Global-- do we just speak into the microphone? Global is for the entire scope of the program, whereas local is just defined within an isolated part. DAVID MALAN: Let's take a look. We're going to hold you to the answer that your classmates gave. If you click on the text, SCOPE in all caps. 

[LAUGHTER] DAVID MALAN: I think we're going to have to take this literally. So we're not going to give those points. We're going to expect exactly what your classmates gave. So unfortunately, we're at minus 500, but you're still in control. But you're still in control-- now you're in control-- well, no. You're still in control. 

STUDENT 2: OK. DAVID MALAN: You're still in control. Yeah, let's go for 500 again. OK. Week 1, 500, Cheng. What are the data types and their sizes? 

[LAUGHTER] 

DAVID MALAN: Oh, I saw a hand over here first. Rob Bowden. 

ROB BOWDEN: A char is 1 byte, a short is two bytes, an int is 4 bytes, a long is 4 bytes, a long long is 8 bytes, a char star is 4 bytes, an int star is 4 bytes, a long long star is 4 bytes. DAVID MALAN: Cheng, what is the correct answer? ROB BOWDEN: Oh, float and double. DAVID MALAN: You left out the part of the reference sheet, but I think we should give it to him for 500. ROB BOWDEN: Yeah. STUDENT: This is biased! ROB BOWDEN: What are you talking about? 

DAVID MALAN: It's OK the points went-- that's right, Team One. I am not a good judge, apparently. All right, we're going to move on. You guys have control. Yale student. We'll do Week 4 for 500 points. I think I saw Team Three. STUDENT 1: You free the memory. DAVID MALAN: You free the memory? Free it. We'll give it to you. All right, Team's One and Three are tied, Team Three has control. What category would you like? 

STUDENT 2: Week Two, 500. 

[DAILY DOUBLE ALARM] 

DAVID MALAN: Amazing. STUDENT 2: Everything? DAVID MALAN: You get to choose your amount. STUDENT 1: Why not? STUDENT 3: Yes. STUDENT 4: All in. STUDENT 2: 500. DAVID MALAN: 500? STUDENT 2: Yes. DAVID MALAN: 500, Daily Double. STUDENT 3: No, you can't. DAVID MALAN: Cheng? No! 

[CHEERING] 

DAVID MALAN: 500 and control of the board. We have-- 

ROB BOWDEN: So a double was a yes or no question? 

[LAUGHTER] 

DAVID MALAN: We have time for one or two more questions in Single Jeopardy. OK. Team Three. Week 0, for 100. What team are you on? STUDENT 5: I'm Two. DAVID MALAN: OK. Team Two. 

STUDENT 5: You use the Say block in MIT Scratch to say, hello, world. 

[LAUGHTER] 

DAVID MALAN: Minus 100. All right, one more question in Single Jeopardy. You guys are still in control. 

STUDENT 2: Week 3, 100. 

DAVID MALAN: Week Three, 100. What is the-- ROB BOWDEN: Team Three. DAVID MALAN: Team Three? OK. We're going with Team Three. STUDENT 3: The best case scenario, or run time? Because the best case scenario is it's in order. 

DAVID MALAN: Let's see what the correct answer is. 

[LAUGHTER] 

DAVID MALAN: All right. Let's move on to Double Jeopardy. 

ALEX TREBEK (RECORDING): This is Jeopardy. 

DAVID MALAN: Double Jeopardy, in this Double Jeopardy we have the categories of Week 5, 6, 7, 8, and 9. 

STUDENT 3: Where did our points go? Where did our points go? 

DAVID MALAN: We are going to manually adjust. There we go. Team Two had 2,000? OK. All right, so now we tossed the coin again and we're giving control to Team Two. Go ahead and choose your category and amount. 

STUDENT 2: We'll go Week 6, 1,000. 

DAVID MALAN: Week 6, 1,000. How does the stack grow? Team Two. 

STUDENT 5: You add a new function into Scope. 

DAVID MALAN: Add a new function to Scope. It grows up. 

[LAUGHTER] 

DAVID MALAN: All right, but you're still in control. 

STUDENT 5: All right, someone else pick. 

STUDENT 6: I'll pick. DAVID MALAN: It is all relative. Even though we tend to draw the stack as growing up, you'll recall that the addresses actually grow in a different direction. But just needed to make Rob happy there. All right, Team Two. 

STUDENT 4: Week 8, 1,000. 

DAVID MALAN: Week 8 for 1,000. True or false, is HTML a programming language? Is there another judge who can decide? 

ROB BOWDEN: It was all me. 

DAVID MALAN: All right, Rob has called. 

ROB BOWDEN: It is not, so false. DAVID MALAN: Rob says false, and the answer is no. [LAUGHTER] CHENG GONG: Wait, wait, wait. Wait, wait, wait. 

DAVID MALAN: All right, Yale student? STUDENT 2: It was a poorly written question, it said true or false, and then it was a question. I object. DAVID MALAN: Noted. We have time for one more Double Jeopardy question. Team Two. 

STUDENT 6: Week 9, 1,000. 

DAVID MALAN: Week 9 for 1,000. What's the difference between ID and class? Team Three? Team Three. 

STUDENT 3: You can apply ID to only one type of thing in HTML, but you can apply class too many different things. 

[APPLAUSE] DAVID MALAN: OK. We'll give it to you. So if we proceed to Final Jeopardy, I think, Team Three just wins, right? So let's do one more question. One more question, Double Jeopardy. 

So at least we can pull-- that's not going to help. It might help Team One. All right, who's in control? Not me, apparently. OK. You guys. Yes, you just got it right. 

STUDENT 2: Week 9, 200. 

DAVID MALAN: Well played, Week 9, 200. What symbol do all PHP-- 

STUDENT 2: Rob. 

DAVID MALAN: Rob? ROB BOWDEN: Cash tag. [LAUGHTER] DAVID MALAN: All right, let's proceed. Let's proceed to Final Jeopardy. Let's have everyone come up with an answer, and we'll have you write it on this slip of paper as we play some music. And then we'll pretend like this was going according to plan. 

All right, so Final Jeopardy category is Week 12. You all have to decide-- I didn't bring pens, no. Pens, please. Thank you. All right, OK. No more pens, please. OK. So Team One is at 0, Team Two is at 0, and Team Three is at 2. You can wager up to $2,000. So let's go ahead and make your wager. Wagers down. And now Cheng is going to reveal the question, then play some music until we adjourn. 

[JEOPARDY THEME PLAYING] 

DAVID MALAN: All right, let us begin here with Team Three. You wagered $1,000 and answered? 

STUDENT 1: 955. 

DAVID MALAN: 955. Team Two here wagered. STUDENT 7: $2,000. DAVID MALAN: $2,000 and your answer was? STUDENT 6: 955. DAVID MALAN: Team Three wagered $2,000, and your answer was? ROB BOWDEN: 955. DAVID MALAN: 955, which is correct. Which means our winner today, I think, is still just Team Three, right? Team Three takes the game! 

[APPLAUSE] 

DAVID MALAN: That then, is it for CS50. Thank you so much for CS50's team. Thank you so much! Thank you so much to our friends on Harvard time. This was CS50. 

[APPLAUSE] 

[MUSIC PLAYING] 

DAVEN FARNHAM: And now Deep Thoughts, by Daven Farnham. How am I supposed to figure out MySQL, if I can't even figure out my present? 

[CHUCKLING]