0:00:11.519,0:00:14.778
This presentation is delivered by the Stanford Center for Professional

0:00:14.778,0:00:21.778
Development.

0:00:22.609,0:00:25.029
So welcome to CS106A.

0:00:25.028,0:00:28.419
If you don't think you should be in CS106A, you think you should be somewhere

0:00:28.419,0:00:30.679
different, now is probably a good time

0:00:30.678,0:00:33.838
to go, not that I would discourage anyone from taking this class. I think we'll have a lovely

0:00:33.838,0:00:34.988
time in here.

0:00:34.988,0:00:39.759
But this class is CS106A or E70A, so if you're,

0:00:39.759,0:00:43.058
like, "Wait. I thought I was in E70A," you're fine. They're the same class; it's the

0:00:43.058,0:00:45.280
same thing. No worries,

0:00:45.280,0:00:48.689
okay? There's four handouts. They're in the back. If you haven't already gotten the handouts because you came in and

0:00:48.689,0:00:51.669
you sat down, don't worry. You can pick them up on the way out. They're

0:00:51.670,0:00:54.300
the same handouts. They'll still be there.

0:00:54.299,0:00:55.939
So

0:00:55.939,0:00:59.519
just a quick introduction. That's what the first four handouts actually give you.

0:00:59.520,0:01:02.680
They give you a little bit of an introduction to the class, what we're gonna cover, some

0:01:02.679,0:01:05.629
logistics for the class and some other stuff. I'm gonna go over all

0:01:05.629,0:01:10.379
that today so we can sort of get a good idea for where we're at, okay? So just a quick show

0:01:10.379,0:01:13.920
of hands before we get into a bunch of things in the class.

0:01:13.920,0:01:17.820
This is kind of an intro-programming course; well, it is. I shouldn't say it's kind of an

0:01:17.819,0:01:19.978
intro-programming course. It is an intro-programming course. And

0:01:19.978,0:01:23.739
it's always good to get an idea as to how much familiarity you may have

0:01:23.739,0:01:25.058
beforehand, okay?

0:01:25.058,0:01:27.239
So just quick show of hands.

0:01:27.239,0:01:31.329
How many people can recognize a computer that's on?

0:01:31.329,0:01:35.829
Good, good. That's the prerequisite for this class. So if you're worried about

0:01:35.829,0:01:38.450
how much previous experience you've had

0:01:38.450,0:01:42.420
or your friend who, like, worked their way through high school by programming for Google or

0:01:42.420,0:01:43.159
whatever,

0:01:43.159,0:01:46.460
don't worry about it because all you need to know in here is basically

0:01:46.459,0:01:50.048
either how to turn a computer on or to recognize a computer that's on if you

0:01:50.049,0:01:53.090
were to walk up to it and it were already to be on, all right?

0:01:53.090,0:01:56.728
So but a little bit more seriously, how many people have actually used a computer

0:01:56.728,0:01:59.049
for anything?

0:01:59.049,0:02:02.420
All right. I would expect most of you. So now, we begin to bump it up

0:02:02.420,0:02:05.409
a notch. How many people have used it for word processing?

0:02:05.409,0:02:09.568
Okay. Most folks. How many people have done web browsing?

0:02:09.568,0:02:13.318
Yeah, I won't ask you what you look at, all right? It's just I don't wanna know.

0:02:13.318,0:02:17.198
How many people have actually created a web page? Okay.

0:02:17.199,0:02:22.629
Fair number. How many people have done any kind of programming before?

0:02:22.628,0:02:23.709
Fair number.

0:02:23.709,0:02:28.618
All right. How about how many folks have done actually programmed in Java before?

0:02:28.618,0:02:34.188
All right. A few folks. How about another language, C, C++,

0:02:34.188,0:02:35.049
BASIC,

0:02:35.049,0:02:37.680
anyone program in BASIC? Yeah,

0:02:37.680,0:02:41.159
oh, I love - that was the first language I learned, and it was kind of

0:02:41.158,0:02:44.900
like the warm and fuzzy, and I felt good. There was actually people who argued that if you learn

0:02:44.900,0:02:48.489
BASIC as your first language, you're brain damaged, then you're just beyond help. But if

0:02:48.489,0:02:49.150
that's the case, we're all

0:02:49.150,0:02:52.120
in the boat together because I'm probably brain damaged as well. The truth is I

0:02:52.120,0:02:54.618
probably am, but that's a whole different story.

0:02:54.618,0:02:57.929
All right. So one thing you should know kind of up front is actually this course

0:02:57.929,0:03:01.489
is gonna be provided eventually somewhere down the line as part of

0:03:01.489,0:03:03.789
Stanford School of Engineering Free Course Initiative,

0:03:03.789,0:03:07.120
which means not only are we recording this course to broadcast to a bunch

0:03:07.120,0:03:09.990
of companies and industry who are watching this course, but we're eventually

0:03:09.990,0:03:12.099
gonna provide it free to the world.

0:03:12.098,0:03:13.979
So how does that impact your life?

0:03:13.979,0:03:16.888
And on the average day, it doesn't at all.

0:03:16.889,0:03:19.749
The only way it does impact your life is just so you should know, the lawyers told me to

0:03:19.748,0:03:20.840
tell you that your

0:03:20.840,0:03:24.250
voice, should you ask a question, may actually be recorded as part of the

0:03:24.250,0:03:25.308
video.

0:03:25.308,0:03:29.079
As a result, your voice may end up going out to thousands of people or millions

0:03:29.079,0:03:30.550
of people in the world.

0:03:30.550,0:03:33.020
If you have an issue with that, come talk to me.

0:03:33.020,0:03:37.000
If you don't, everything is just fine, all right? Don't worry. We're not gonna put your picture up

0:03:37.000,0:03:39.748
or anything like that. You might wanna be on the video, like, "Hey,

0:03:39.748,0:03:40.609
ma, I'm on

0:03:40.609,0:03:43.889
TV." We decided that we're just gonna not show anyone actually on the video,

0:03:43.889,0:03:46.129
but your voice may actually get recorded, okay?

0:03:46.128,0:03:49.828
Now, along those lines, you may also notice there are some microphones in the room.

0:03:49.829,0:03:52.709
So when you wanna ask a question, please make sure to use the microphone

0:03:52.709,0:03:56.209
because that's not only good for people in here to be able to hear your question,

0:03:56.209,0:03:59.579
it's also good for all the folks that this is getting broadcast to because not

0:03:59.579,0:04:02.289
only are we gonna broadcast to the world, but there's actually some folks who are sort

0:04:02.288,0:04:05.578
of watching this live now in various companies in Silicon Valley.

0:04:05.579,0:04:08.389
So it's real important that you actually use the microphone, so just remember that. And

0:04:08.389,0:04:11.130
every once in a while, I might get on your case and be, like, "Please use the microphone."

0:04:11.129,0:04:14.599
I'm not trying to be argumentative or anything. I just wanna make sure we

0:04:14.599,0:04:16.488
pick up all the audio, all

0:04:16.488,0:04:19.560
right? So with that said, a little bit of an introduction. That's kind of a way of background.

0:04:19.560,0:04:22.550
I didn't give you any sort of introduction. So just to introduce myself, my name's

0:04:22.550,0:04:25.379
Mehran Sahami. I'm the professor for the class.

0:04:25.379,0:04:28.228
Don't call my Professor Sahami, way too formal.

0:04:28.228,0:04:31.899
Don't call me Mr. Sahami. That, I think of my dad.

0:04:31.899,0:04:35.098
And don't call me Mrs. Sahami, or we're gonna have issues, all right?

0:04:35.098,0:04:36.219
So just call me

0:04:36.220,0:04:40.520
Mehran. We'll get along. It's just fine, all right? It's to keep things a little bit more

0:04:40.519,0:04:43.490
informal, but that way it's a little bit easier to discuss stuff as you go along.

0:04:43.490,0:04:46.949
There is also a head TA for the class, Ben Newman, who's standing up there. Get to know

0:04:46.949,0:04:47.980
Ben.

0:04:47.980,0:04:51.700
He has all the real power in this class. I'm just kind of the monkey that gets up here and

0:04:51.699,0:04:54.159
gives the lectures. But Ben really is the one who's got all the

0:04:54.160,0:04:55.189
power.

0:04:55.189,0:04:57.829
Along with the head TA for the class, we have a large section leading staff. So

0:04:57.829,0:05:03.519
the section leaders here, could you stand up if you're here? They're kind

0:05:03.519,0:05:06.408
of all over the place, some over here, some over there, and some over there. As

0:05:06.408,0:05:09.889
you can see, there's a pretty large number of folks. And this isn't even all of them.

0:05:09.889,0:05:12.759
We sort of have more - we just can't stuff them all into the room -

0:05:12.759,0:05:16.800
who are section leaders for the class, and these folks are all here to make sure

0:05:16.800,0:05:20.189
that everyone in this class has as good an experience as possible when

0:05:20.189,0:05:22.889
we're sort of going through the class. And the best way to reach all of us is

0:05:22.889,0:05:26.300
email. So on Handout No. 1, you get my email and Ben's email.

0:05:26.300,0:05:30.090
We'll tell you how to sign up for section. That's how you'll meet your section leader and get your section

0:05:30.089,0:05:33.810
leader's email. That will all be coming soon. But email really is kind of a happy form of

0:05:33.810,0:05:35.250
communication to

0:05:35.250,0:05:37.059
get a hold of us, okay?

0:05:37.059,0:05:40.460
So with that said, I wanna tell you a little bit about this class and kind of

0:05:40.459,0:05:43.478
what we're gonna do in here and what you should expect and make sure that

0:05:43.478,0:05:43.930


0:05:43.930,0:05:47.519
you don't feel scared off by this class, okay? Because it really is meant to sort of be an

0:05:47.519,0:05:48.750
interesting time.

0:05:48.750,0:05:52.579
But one question that comes up is why is this class called Programming

0:05:52.579,0:05:53.219
Methodology,

0:05:53.220,0:05:56.259
right? Why don't we just call this class, like,

0:05:56.259,0:05:57.679
Programming with Java?

0:05:57.678,0:06:00.768
And the real reason for that is that programming methodology is about good

0:06:00.769,0:06:03.759
software engineering principles. It's about something that's much larger than

0:06:03.759,0:06:07.139
just programming. So some people, like, they'll go and get a book somewhere and they'll

0:06:07.139,0:06:09.859
think they learned how to program by just reading the book. And they're,

0:06:09.858,0:06:12.688
like, "Oh, I know how to program. Isn't that great?" And it's, like,

0:06:12.689,0:06:15.729
yeah, you might know the mechanics of the language, but the mechanics of the

0:06:15.728,0:06:18.829
language are nothing compared to understanding the software engineering

0:06:18.829,0:06:19.658
principles

0:06:19.658,0:06:23.060
that go into actually developing a software system. And that's what you're gonna

0:06:23.060,0:06:26.189
learn about in this class. You're gonna learn a lot of those principles. But in order

0:06:26.189,0:06:27.010
to be able to use

0:06:27.009,0:06:30.620
those principles and apply them, you also need to have the language to program in,

0:06:30.620,0:06:33.850
and that language that we're gonna use in this class is Java. So the way I like to

0:06:33.850,0:06:36.930
think about it and the way I tell a lot of people is writing a good program or

0:06:36.930,0:06:40.310
learning how to program is like learning to be a good

0:06:40.310,0:06:41.649
essay writer. And you're, like, "Oh, but part

0:06:41.649,0:06:45.519
of the reason I'm taking this class, Mehran, is that I don't like writing essays." That's fine.

0:06:45.519,0:06:49.028
It's okay. Trust me. I didn't like writing essays either. But

0:06:49.028,0:06:52.389
the whole point is that when you write an essay, it's not a formulated kind of

0:06:52.389,0:06:55.538
thing. You're, like, "Well, what about five-paragraph essays?" Yeah, just block that from

0:06:55.538,0:06:59.818
your mind. That was a bad time, right? That was just, like, '70s education at work.

0:06:59.819,0:07:02.968
It's not a formulated kind of thing. There's an art to writing an essay,

0:07:02.968,0:07:05.959
right? In order to write an essay, you need to know a language. You need to know English or German or

0:07:05.959,0:07:08.079
Hindi or whatever language you wanna use,

0:07:08.079,0:07:10.659
but then you use that language to write an essay.

0:07:10.660,0:07:13.710
Just knowing the language doesn't make you a good essay writer though. Being

0:07:13.709,0:07:16.498
a good essay writer makes you a good essay writer.

0:07:16.499,0:07:19.709
So that's the same difference in programming and software engineering. Knowing the

0:07:19.709,0:07:23.228
language, in order to be a good programmer, like a good essayist,

0:07:23.228,0:07:26.829
you need to know a language to write your programs in, whether that be Java or C or

0:07:26.829,0:07:29.609
C++ or whatever. Here we're gonna use Java.

0:07:29.610,0:07:33.229
But just knowing the language doesn't make you a good software engineer and

0:07:33.228,0:07:36.478
doesn't make you understand what the principles are of writing good software,

0:07:36.478,0:07:39.558
which is what you're also gonna get in this class in addition to the language, and that's kind of

0:07:39.559,0:07:41.719
a key thing to stress.

0:07:41.718,0:07:44.759
So if you're sort of worried, if you were kind of looking around and you saw a bunch of people raising

0:07:44.759,0:07:46.160
their hands when I asked, "Do

0:07:46.160,0:07:49.080
you have any previous programming experience?" and some folks raised their

0:07:49.079,0:07:53.079
hands, and you got a little worried and you're like, "Oh, am I gonna be in some sense at

0:07:53.079,0:07:56.659
a disadvantage because I haven't done any programming before?" The answer, plain and

0:07:56.660,0:07:58.409
simple, is no, okay? You're

0:07:58.408,0:08:00.819
gonna learn everything you need to learn from the first principle because as a

0:08:00.819,0:08:01.900
matter of fact,

0:08:01.899,0:08:05.579
in some cases you might be in slightly better shape. That's not necessarily to say

0:08:05.579,0:08:07.680
that that's the way it will be. But

0:08:07.680,0:08:11.228
how many people are Star Wars fans? Just wondering. Anyone? I'm

0:08:11.228,0:08:14.308
talking about the old-school, original, like, three movies. Those were so good, and

0:08:14.309,0:08:17.949
we're not - no George R. Binks here, all right?

0:08:17.949,0:08:22.090
So if you remember - and sort of I'm a big Star Wars fan, and that's just a whole

0:08:22.089,0:08:22.919
separate point.

0:08:22.920,0:08:26.460
But in the second movie, Yoda actually said something which I thought was quite

0:08:26.459,0:08:27.979
profound, which is he says

0:08:27.980,0:08:31.030
sometimes you have to unlearn what you have learned.

0:08:31.029,0:08:34.448
And one of the things we actually find is that some people who are self-taught programmers,

0:08:34.450,0:08:36.909
some of them are just fine, and some of them are very good.

0:08:36.909,0:08:39.828
But some of them have picked up some really bad habits along the way, and it's

0:08:39.830,0:08:41.460
like being a bad essay writer.

0:08:41.460,0:08:45.070
And to go from being a bad essay writer to a good essay writer, in some cases, can

0:08:45.070,0:08:46.280
actually be harder

0:08:46.279,0:08:49.350
than from not being an essay writer to being a good essay writer because you

0:08:49.350,0:08:51.339
have to unlearn the bad habits.

0:08:51.339,0:08:54.450
So if you're worried about, "Oh, I've had no previous experience,"

0:08:54.450,0:08:57.460
don't worry. You're okay, blank slate, you're just fine. And now if you're thinking,

0:08:57.460,0:09:00.940
"Oh, I have some previous experience. Do I have bad habits?" Don't worry. You'll be

0:09:00.940,0:09:04.880
fine, too, okay? So it's all gonna work out.

0:09:04.879,0:09:07.720
So the next question that kind of comes up - hopefully that helps put some of your fears

0:09:07.720,0:09:08.300
aside.

0:09:08.299,0:09:12.120
Another one of the things is that we really strive to make everyone successful in this

0:09:12.120,0:09:13.669
class, okay? At some other schools,

0:09:13.669,0:09:16.698
people wanna do computer science or they wanna do an

0:09:16.698,0:09:19.438
engineering major or whatever. And you come into the first day of class, and they say,

0:09:19.438,0:09:23.088
"Oh, only one third of you are actually gonna make it through this program. And

0:09:23.089,0:09:25.800
look to the person to your left and look to the person to your right, and only one

0:09:25.799,0:09:28.370
of you will make it through." And you're, like, "Oh,

0:09:28.370,0:09:29.948
man, that's real nice."

0:09:29.948,0:09:33.438
It's not like that here. As a matter of fact, we want all of you to be extremely

0:09:33.438,0:09:37.248
successful in this class, which is why we have a huge course staff, which is why over years

0:09:37.249,0:09:40.379
and years we've refined how we do a lot of the teaching in this class

0:09:40.379,0:09:43.730
to make sure you have the best possible experience and to make sure that everyone

0:09:43.730,0:09:44.990
gets through.

0:09:44.990,0:09:48.779
And the important thing about that is that you're not competing against anyone

0:09:48.779,0:09:51.339
except yourself in this class. It's not like we're gonna have a curve and

0:09:51.340,0:09:54.350
we're gonna say, "Oh, we have a certain number of "F"s and a certain number of

0:09:54.350,0:09:56.129
"D"s and a certain number of "C"s."

0:09:56.129,0:09:59.120
All we really have going into it is an expectation that when you get out of

0:09:59.120,0:10:01.500
here, there's a set of stuff we want you to know.

0:10:01.500,0:10:03.220
And if you know that stuff well,

0:10:03.220,0:10:04.170
you get an "A."

0:10:04.169,0:10:06.679
And if everyone knows that stuff well,

0:10:06.679,0:10:07.799
everyone gets an "A."

0:10:07.799,0:10:11.019
And I got no problems with that. Registrar might have a problem with that, but that's okay.

0:10:11.019,0:10:12.720
You don't need to worry about that.

0:10:12.720,0:10:14.990
So you don't need to think about, oh,

0:10:14.990,0:10:18.379
is someone else doing better than you or whatever. And we'll talk about

0:10:18.379,0:10:21.340
issues of collaboration in just a little bit. All you need to think about is

0:10:21.340,0:10:24.670
learning the stuff yourself as well as you possibly can, and you'll be just fine

0:10:24.669,0:10:26.729
and you'll get a good grade, okay?

0:10:26.730,0:10:28.909
So that's really all we ask,

0:10:28.909,0:10:29.909
which is not

0:10:29.909,0:10:33.379
a trivial amount, right? It requires you to really understand the material.

0:10:33.379,0:10:36.340
So another question that comes up is are you in the right place, right? This

0:10:36.340,0:10:39.070
isn't the only introductory programming class at Stanford. And so I wanna spend a

0:10:39.070,0:10:41.890
little bit of time making sure you actually are in the right place

0:10:41.889,0:10:44.519
by going over some of the different options. So right

0:10:44.519,0:10:47.399
now, as you know, you're in CS106A.

0:10:47.399,0:10:50.480
And CS106A, we're sort of happy over here,

0:10:50.480,0:10:51.050
right? As

0:10:51.049,0:10:54.870
a matter of fact, we're not only happy, we're happy and we're also a little bit loopy,

0:10:54.870,0:10:56.919
right?

0:10:56.919,0:11:00.039
There is no previous programming experience required, as I mentioned, right? All you

0:11:00.039,0:11:04.230
need to know is basically if you can get to a computer and know how to

0:11:04.230,0:11:06.710
figure out that it's on, you're in good shape.

0:11:06.710,0:11:10.850
But what 106A does is it's a real rigorous class. You learn programming in

0:11:10.850,0:11:14.330
here, and you learn it in a way that makes you ready to be an engineer if you so

0:11:14.330,0:11:15.829
choose to be an engineer.

0:11:15.828,0:11:18.218
That's not to say you're all gonna be engineers. I would love for all of you to

0:11:18.219,0:11:21.309
be computer science majors, but statistics in the past show only about

0:11:21.308,0:11:24.278
6 percent of you will be computer science majors. That's not because we

0:11:24.278,0:11:25.958
turn anyone off to computer science;

0:11:25.958,0:11:29.169
it's because we make programming accessible to so many people

0:11:29.169,0:11:32.099
that you don't have to be a computer science or a Double E or even an

0:11:32.100,0:11:34.960
engineering major to do extremely well in the class. And we actually have sort

0:11:34.960,0:11:38.730
of a significant percentage of the entire campus undergraduate student body

0:11:38.730,0:11:42.360
at Stanford actually goes through this class and does well, okay?

0:11:42.360,0:11:45.778
So don't worry if you're, like, "Oh, but I'm not really a CS person." I hope

0:11:45.778,0:11:49.409
we'll turn you into one by the end of the class. No, it's okay. But

0:11:49.409,0:11:53.360
you'll be prepared if that's what you wanna do. So this leads into a whole

0:11:53.360,0:11:54.449
engineering sequence

0:11:54.448,0:11:58.799
that can go on to other engineering majors or the computer science majors.

0:11:58.799,0:12:02.019
If you're, like, "Huh, I'm not sure if that's really what I wanna do. As a matter of fact,

0:12:02.019,0:12:04.600
I'm so sure that's not what I wanna do,

0:12:04.600,0:12:07.300
I only wanna get the general educational requirement out of the way, and

0:12:07.299,0:12:11.049
I'm positive there is nothing else I wanna do. Really, no matter how much I like

0:12:11.049,0:12:15.089
it, like, there is no way you're gonna drag me into anything that would involve

0:12:15.090,0:12:17.040
anything remotely techie."

0:12:17.039,0:12:21.879
They're the class CS105. And this is happy,

0:12:21.879,0:12:22.489
yeah,

0:12:22.489,0:12:25.990
this is kind of, oh, we're happy in our little happy world.

0:12:25.990,0:12:30.500
And I don't wanna say it's holding hands and singing, "Kumbaya," because that's not what it is. It's a real

0:12:30.500,0:12:34.120
class.

0:12:34.120,0:12:38.060
But it's meant to be a general educational requirement, right? It

0:12:38.059,0:12:41.989
doesn't lead into the 106s. It's meant to be its own self-contained class.

0:12:41.990,0:12:45.459
You do some Java script in there. You do a little bit of what computers are about.

0:12:45.458,0:12:48.539
Computers in society is a good time. We all hold hands. We're all happy. I don't

0:12:48.539,0:12:50.839
teach the class, so I don't actually hold hands.

0:12:50.840,0:12:54.430
But it's a fun time, okay? It just doesn't lead to anything else. So think of this as

0:12:54.429,0:12:57.959
kind of a terminal class, right? So it's sort of like, well, we'll hook you up to the

0:12:57.960,0:12:59.570
IV drip. And

0:12:59.570,0:13:02.390
you're, like, "Well, 106A, you told me I don't need any previous background.

0:13:02.389,0:13:03.100
Well,

0:13:03.100,0:13:07.589
hey, Mehran, I got lots of background. I got so much background, it hurts. I got AP

0:13:07.589,0:13:09.749
background, I got working through school doing software engineering

0:13:09.749,0:13:10.680
background.

0:13:10.679,0:13:12.759
I'm not sure I should be here."

0:13:12.759,0:13:16.710
That could be the case. We have another class called CS106X, and as

0:13:16.710,0:13:21.560
the "X" kind of implies, it's sort of the extreme games version of the class. No, it

0:13:21.559,0:13:23.888
stands for accelerated, right, because

0:13:23.889,0:13:28.580
"A" was already taken, so we had to come up with something else.

0:13:28.580,0:13:33.250
So the way CS106X works is it really is a very fast-paced class. It's

0:13:33.250,0:13:35.649
meant for people who've got previous AP exam

0:13:35.649,0:13:37.659
credit, like, got a 4 or 5 on the AP,

0:13:37.659,0:13:41.110
or have had significant and prior programming experience before.

0:13:41.110,0:13:44.460
If you're not sure which one of these classes is for you, you can come talk to me

0:13:44.460,0:13:47.530
afterwards, or I'd also encourage you, you could go to pick up the syllabus for

0:13:47.529,0:13:50.399
CS106X and compare it to CS106A.

0:13:50.399,0:13:55.458
This class is all in C++. And if you're thinking, "Hey, Mehran, I'm doing 106A. I wanna learn

0:13:55.458,0:13:59.278
Java and C++," don't worry. You'll eventually, if you so choose, take a

0:13:59.278,0:14:03.048
class called CS106B, which is where this class sort of leads to, which

0:14:03.048,0:14:03.909
is

0:14:03.909,0:14:07.199
C++ and all of the other stuff you would have learned in this accelerated

0:14:07.200,0:14:08.060
class,

0:14:08.059,0:14:11.459
okay? So you still certainly have that course path. So don't let anyone make you think -

0:14:11.460,0:14:14.850
I know a lot of times, and especially for Stanford students, you come in here and you're, like, "Well,

0:14:14.850,0:14:17.800
every class I took in high school was like an honors or an AP class,

0:14:17.799,0:14:20.969
or if it wasn't an honors or an AP class, like, I had to tie half my brain

0:14:20.970,0:14:23.460
before my head because I'm just that hardcore."

0:14:23.460,0:14:25.560
And so everyone just wants to, like, do

0:14:25.559,0:14:29.659
the most hardcore thing they can, right? And what I'm here to tell you is that

0:14:29.659,0:14:32.350
you shouldn't necessarily think about it that way. You should think about it as where

0:14:32.350,0:14:34.649
you feel most comfortable.

0:14:34.649,0:14:38.459
Some number of years ago, let's just say greater than 10, maybe 15, I was

0:14:38.460,0:14:40.530
sitting where you're sitting right now,

0:14:40.529,0:14:40.809
literally.

0:14:40.809,0:14:44.859
I was in CS106A in Terman Auditorium as a freshman,

0:14:44.860,0:14:49.279
okay? It was perfectly fine. It worked out. I went to grad school, did the faculty

0:14:49.279,0:14:53.549
thing. It's just fine. It will open your doors to CS. You're not at any kind of

0:14:53.549,0:14:56.539
disadvantage by starting here. So know where you've been, literally. Like, that seat

0:14:56.539,0:14:58.439
right there was where I was

0:14:58.440,0:15:00.280
most of the time.

0:15:00.279,0:15:03.259
So just something to keep in mind in terms of the different options that are actually

0:15:03.259,0:15:04.319
available to you.

0:15:04.320,0:15:07.670
Now, with that said, let's just assume for the rest of this lecture that this is the

0:15:07.669,0:15:11.029
right place for you. And if it's not, well, afterwards we can kind of talk about it,

0:15:11.029,0:15:13.970
or if you really are convinced now that it's not the right place, you can feel free and try

0:15:13.970,0:15:14.980
to

0:15:14.980,0:15:17.649
scramble over 20 of your classmates and actually leave the room, which is

0:15:17.649,0:15:20.069
probably impossible. All right.

0:15:20.070,0:15:23.150
So a few other things you should know, some mechanics. So Handout No. 1, should

0:15:23.149,0:15:25.269
you wanna follow along at home,

0:15:25.269,0:15:27.429
is the class web page.

0:15:27.429,0:15:32.039
And so all the stuff that we think of as course materials, including online

0:15:32.039,0:15:34.990
copies of the handouts, things that you'll need to do for the assignments, announcements

0:15:34.990,0:15:36.220
related to the class

0:15:36.220,0:15:37.990
are all on the class web page,

0:15:37.990,0:15:44.990
which is

0:15:46.750,0:15:48.840
www.stanford.edu/class/cs106a.

0:15:48.840,0:15:52.230
And because that's just kind of a whole bunch to remember, we make your life easy

0:15:52.230,0:15:56.950
and so there is an equivalent form of the URL, which is just

0:15:56.950,0:16:00.860
cs106a.stanford.edu, which is the easy thing to remember. You put that in, it'll take

0:16:00.860,0:16:03.039
you to the class web page, okay?

0:16:03.039,0:16:05.730
And you should check that regularly because all the

0:16:05.730,0:16:09.058
announcements and handouts - we'll give out hard copies of all the handouts in class, but

0:16:09.058,0:16:11.688
should you happen to miss class for whatever reason, you wanna go print

0:16:11.688,0:16:14.808
whatever copies of the handouts we're actually giving out, you can find them all on

0:16:14.808,0:16:16.439
the web page, okay?

0:16:16.440,0:16:20.440
Now, there's this funky thing about units. So you may have noticed that this class is for three

0:16:20.440,0:16:23.800
to five units, and that kind of brings up the natural question, "Should I take it for three

0:16:23.799,0:16:25.329
or five units?"

0:16:25.330,0:16:29.300
If you're an undergrad, you take it for five units, end of story. That's life in the city.

0:16:29.299,0:16:30.609
Congratulations. Five units.

0:16:30.610,0:16:34.279
If you're a graduate student, you can have the option of taking it for three

0:16:34.279,0:16:38.129
units if you want, if you're gonna run into some unit cap.

0:16:38.129,0:16:41.360
It doesn't change the amount of work you have to do.

0:16:41.360,0:16:42.818
Welcome to graduate school.

0:16:42.818,0:16:44.509
Same work, fewer units.

0:16:44.509,0:16:47.639
So that's just the way life is. If you have a unit cap and you're a grad student, in

0:16:47.639,0:16:50.919
three units you can take it if you want. You can take it for five if you want as well. If you're an

0:16:50.919,0:16:53.240
undergrad, you take it for five, all right?

0:16:53.240,0:16:55.938
So why is it five units? And you might think, "Hey,

0:16:55.938,0:16:59.428
this class only meets three times a week. How come it's five units?" Well, it actually

0:16:59.428,0:17:02.578
has a fourth meeting every week, which is your section, and that's something you

0:17:02.578,0:17:04.279
should sign up for.

0:17:04.279,0:17:06.509
So how you actually sign up for your section

0:17:06.509,0:17:10.618
is sections are at a bunch of different times. You don't sign up for them in

0:17:10.618,0:17:13.118
Axess, even though they're all kind of listed in the time schedule. That's not where

0:17:13.118,0:17:16.068
you sign up for them. In Axess, you just sign up for the class.

0:17:16.068,0:17:20.898
How you sign up for a section is you go to a website, cs198.stanford.edu/section

0:17:20.900,0:17:22.000


0:17:22.000,0:17:24.920


0:17:24.920,0:17:30.519
and this will give us a list of preferences for

0:17:30.519,0:17:33.730
section times that you wanna sign up for, and there's some matching process that goes on.

0:17:33.730,0:17:37.450
It takes all your preferences into consideration with the whole system, and

0:17:37.450,0:17:39.190
eventually you get an email

0:17:39.190,0:17:42.460
by sometime early next week that tells you what section you're in. And section's 50

0:17:42.460,0:17:45.659
minutes, once a week. It's required to go to. It's actually gonna be part of your class

0:17:45.659,0:17:48.640
participation grade, which we'll talk about in just a bit, okay?

0:17:48.640,0:17:52.920
When do these sign-ups happen? They happen between 5:00 p.m. this Thursday

0:17:52.920,0:17:56.130
is when they go up. So if you try to go there now, you can't sign up. Remember 5:00

0:17:56.130,0:17:59.150
p.m. Thursday. So they're up, and then they're down

0:17:59.150,0:18:03.980
at 5:00 p.m. on Sunday, okay? So

0:18:03.980,0:18:06.769
make sure you sign up probably this weekend. If you're planning on being out of

0:18:06.769,0:18:09.990
town this weekend, you wanna sign up before you go. Sign up early, but don't

0:18:09.990,0:18:13.529
sign up often because you only need one section, okay?

0:18:13.529,0:18:17.119
If you're an SCPD student - every once in a while you'll hear me refer to SCPD

0:18:17.119,0:18:20.119
students. That stands for Stanford Center for Professional Development.

0:18:20.119,0:18:23.109
They are the folks in industry who actually take this class

0:18:23.109,0:18:26.389
via broadcast. If you're an SCPD student, you're automatically enrolled for a section,

0:18:26.390,0:18:30.259
so you don't actually need to do this, and your section will meet at - so for SCPD

0:18:30.259,0:18:33.929
- and if you're wondering what an SCPD student is, you're not one, okay?

0:18:33.929,0:18:40.259
So SCPD section meets Friday from 1:15 to 2:05. It meets

0:18:40.259,0:18:44.089
live, if you wanna go there live, in Skilling Auditorium. But if you're

0:18:44.089,0:18:48.269
watching it remotely, it meets on Channel E2. I

0:18:48.269,0:18:52.609
know it seems weird to say it meets on channel - what does that mean? It meets on

0:18:52.609,0:18:56.869
Channel E2, okay? That is grammatically the correct way of saying it.

0:18:56.869,0:18:57.619
All right.

0:18:57.619,0:19:01.529
So there's a little bit more administrative stuff. Now,

0:19:01.529,0:19:05.049
textbooks, right? Textbooks, there's nothing quite like the extortion that is

0:19:05.049,0:19:07.039
textbooks. So there are

0:19:07.039,0:19:09.539
two textbooks that are required for this class. Well, one's a course reader and

0:19:09.539,0:19:12.789
one's a textbook. The course reader is called, Karel the Robot Learns Java. You

0:19:12.789,0:19:16.079
can pick it up at the bookstore. It's relatively cheap. It was actually written by Eric

0:19:16.079,0:19:19.799
Roberts here. And surprisingly enough, the textbook for the class was also written by

0:19:19.799,0:19:23.180
Eric Roberts, The Art and Science of Java, which is available now in your local

0:19:23.180,0:19:24.630
bookstore,

0:19:24.630,0:19:27.710
including the bookstore on campus, so you can go and pick up a copy of this.

0:19:27.710,0:19:30.690
So both these things you actually wanna have because they're required for the

0:19:30.690,0:19:33.759
class. We'll go through all of them. We'll go through basically everything except

0:19:33.759,0:19:35.729
the last chapter of this book. So you

0:19:35.729,0:19:38.359
sort of get your money's worth. We're just gonna do it a little bit out of

0:19:38.358,0:19:40.689
order, but we'll go through the whole thing,

0:19:40.690,0:19:42.809
okay? So email,

0:19:42.809,0:19:45.869
how many of you have email accounts? All

0:19:45.869,0:19:48.689
right. I will ask the reverse question because I think at this point, some people just don't

0:19:48.690,0:19:49.799
wanna put up their hands.

0:19:49.799,0:19:53.230
How many people don't have email accounts?

0:19:53.230,0:19:56.240
Odd how that is not the complement of the folks who had their hands up

0:19:56.240,0:19:57.220
previously.

0:19:57.220,0:20:00.910
Email's required for this class. Chances are, by being at Stanford, you've already gotten an

0:20:00.910,0:20:03.769
email account through your SUNet ID, but if you don't have an email account, get

0:20:03.769,0:20:06.210
an email account and that's how you'll stay in contact with us. That's how we'll stay in

0:20:06.210,0:20:09.059
contact with you, except we'll also meet with you live in person,

0:20:09.059,0:20:12.109
but email is kind of the general method for communication. As a matter of fact, for your

0:20:12.109,0:20:15.178
first assignment, and part of your first assignment is to send us an email,

0:20:15.179,0:20:16.900
just because we love you

0:20:16.900,0:20:18.740
and we don't get enough email as it is.

0:20:18.740,0:20:21.470
So you need to have an email account to be able to do that. So if you have not

0:20:21.470,0:20:24.250
already, you can kind of get ahead of the game and go set up your email

0:20:24.250,0:20:26.720
account. Now, don't worry. You'll get the first assignment next time. So you still get, like,

0:20:26.720,0:20:30.350
two days of breathing space before your assignment goes out, okay?

0:20:30.349,0:20:33.149
There is also gonna be lots of handouts in the class. They'll be either given out in class,

0:20:33.150,0:20:36.970
well, they will be given out in class, but we'll also post them online in case you miss them.

0:20:36.970,0:20:40.558
And how much real work do you do in this class? That's always kind of an interesting

0:20:40.558,0:20:40.898
question.

0:20:40.898,0:20:43.379
So let's talk a little bit about assignments

0:20:43.380,0:20:46.620
and a little bit of other logistical things.

0:20:46.619,0:20:49.679
So assignments,

0:20:49.680,0:20:54.430
we'll just call them the dreaded assigns. There are seven programming assignments.

0:20:54.430,0:20:57.120
And if you look at the syllabus Handout No. 2, it tells you when all of them

0:20:57.119,0:21:01.149
are due all the way through by day, so you can plan out your whole quarter. It's

0:21:01.150,0:21:03.670
just that much fun, okay?

0:21:03.670,0:21:07.269
And these seven programming assignments are weighted slightly more toward the

0:21:07.269,0:21:09.930
last assignments because the assignments will tend to get more complicated. That doesn't

0:21:09.930,0:21:11.990
necessarily mean there'll be more programming;

0:21:11.990,0:21:14.589
it just means conceptually, they'll become more complicated,

0:21:14.589,0:21:17.789
so we tend to weigh them more toward the end of the class. So the later assignments count

0:21:17.789,0:21:19.879
more than the early assignments.

0:21:19.880,0:21:25.150
How you're gonna be actually doing your programming is using a little tool called Eclipse.

0:21:25.150,0:21:28.480
And Eclipse thankfully is free, so you don't have to pay for it. As a matter of

0:21:28.480,0:21:31.450
fact, you can download it from the CS106A website. And if you're wondering

0:21:31.450,0:21:34.600
how you do that, don't worry. We'll give you a handout next class that explains

0:21:34.599,0:21:36.699
to you the whole grueling process

0:21:36.700,0:21:38.509
of downloading and installing Eclipse.

0:21:38.509,0:21:43.230
And you can use this either on the Mac or the PC. So if you have your own

0:21:43.230,0:21:46.480
computer, you can certainly work on this yourself. You just download it to your

0:21:46.480,0:21:49.110
own machine. We'll explain the whole process in a handout.

0:21:49.109,0:21:52.649
If you don't have your own computer, the public computer clusters on campus

0:21:52.650,0:21:55.710
will have Eclipse installed on them, and so you can use Eclipse there. So you're

0:21:55.710,0:21:58.730
sort of happy to go either way, okay? Now,

0:21:58.730,0:22:01.429
the important thing, remember I mentioned that whole notion of software

0:22:01.429,0:22:03.780
engineering in the class, and that's something we take really seriously, so

0:22:03.779,0:22:06.349
seriously as a matter of fact that when you turn in your assignments, one thing we could do is we could take

0:22:06.349,0:22:07.269
your assignments

0:22:07.269,0:22:11.348
and we could just kind of look at it and go, "Yeah, interesting, 'B.' Here you go.

0:22:11.348,0:22:12.589
Thanks for playing."

0:22:12.589,0:22:16.649
And you don't learn a whole lot from them. So in order to actually learn a lot from

0:22:16.650,0:22:19.280
your assignments, we could take your assignment and write a whole bunch of

0:22:19.279,0:22:22.678
comments on it and hand it back to you. Even that's kind of not enough.

0:22:22.679,0:22:26.528
What really is a little bit more that makes it more fun is every week after

0:22:26.528,0:22:29.769
you turn in your assignment and your section leader looks it over and grades it,

0:22:29.769,0:22:32.940
you'll actually meet with your section leader for about 10 to 15 minutes

0:22:32.940,0:22:35.278
every week or every time an assignment is due

0:22:35.278,0:22:38.038
to actually go over in something referred to as interactive grading. And it's

0:22:38.038,0:22:41.450
a chance to sit there and talk with an actual human being about what's good in

0:22:41.450,0:22:44.739
your assignment, what are some of the things you need to work on, what are some of the

0:22:44.739,0:22:47.940
software engineering principles you need to develop. And that way, you can really

0:22:47.940,0:22:52.499
sort of get more detailed information and be able to ask questions to develop

0:22:52.499,0:22:55.730
yourself as a programmer as well as get help if you need help,

0:22:55.730,0:22:59.759
okay? And that's in addition to going to section, going to class and all that stuff. So

0:22:59.759,0:23:02.869
it's another 15 minutes a week. You'll actually schedule that time with your

0:23:02.869,0:23:04.519
section leader on a regular basis

0:23:04.519,0:23:07.670
when you're gonna have interactive grading or just affectionately

0:23:07.670,0:23:11.560
referred to as IGs because at Stanford, everything's just short and we just can't

0:23:11.559,0:23:13.809
say, like, psychology; we have to say psyche.

0:23:13.809,0:23:17.470
So it's IG. Just remember that, all right?

0:23:17.470,0:23:20.450
And then how are these things graded? So the other thing we could do is I told you

0:23:20.450,0:23:22.600
we could just write "B" and hand it back to you.

0:23:22.599,0:23:25.309
But we found that that's not really great because people get all wrapped

0:23:25.309,0:23:27.339
around the axle about the grade.

0:23:27.339,0:23:30.988
And so for a while, we did numbers and we're, like, huh, why don't we give a number between 1 and

0:23:30.989,0:23:33.079
20? And so what happens there?

0:23:33.079,0:23:35.798
People get all wrapped around the axle about numbers.

0:23:35.798,0:23:39.099
So then we thought, huh, what was a happier time when we were in school?

0:23:39.099,0:23:42.730
I remember when we were in school, and we used to get back assignments and they

0:23:42.730,0:23:45.289
had, like, smiley faces on them.

0:23:45.289,0:23:48.659
Well, we can't do that because then it doesn't appear to be a rigorous Stanford

0:23:48.660,0:23:49.410
class.

0:23:49.410,0:23:52.440
So instead of the smiley face,

0:23:52.440,0:23:54.330
we come up with something else,

0:23:54.329,0:23:59.009
which looks surprisingly like this. It's kind of involved to actually draw, so I need to

0:23:59.009,0:24:04.980
erase the board to do it. Check.

0:24:04.980,0:24:07.490
That's kind of the beginning of our grading scale, okay?

0:24:07.490,0:24:11.529
And the way our grading scale works is we start off with a check in the middle,

0:24:11.529,0:24:14.899
which says this is a pretty solid program. It meets all the requirements

0:24:14.900,0:24:19.169
for the program. Maybe it's got a little problem here or there, but it's a check.

0:24:19.169,0:24:22.950
Then we have sort of two grades on the two sides of it: check plus and check

0:24:22.950,0:24:23.980
minus.

0:24:23.980,0:24:26.048
Check plus is, like,

0:24:26.048,0:24:27.168
solid.

0:24:27.169,0:24:31.520
You did a great job; you got everything right; things look good, a nice style in

0:24:31.519,0:24:35.619
your program, nice software engineering, and the program works flawlessly.

0:24:35.619,0:24:39.308
Good job. This is like total "A."

0:24:39.308,0:24:42.920
Check is kind of like, yeah, you're sort of there. It's kind of like "A" minus, "B" plus,

0:24:42.920,0:24:45.110
maybe on some occasions "B."

0:24:45.109,0:24:47.399
But it's kind of like it's pretty good work; you're in pretty good

0:24:47.400,0:24:48.710
shape here.

0:24:48.710,0:24:52.440
And so a lot of grades in this class ends up being check pluses and checks, and if that's

0:24:52.440,0:24:55.070
the case, you're perfectly fine grade-wise.

0:24:55.069,0:24:59.009
Check minus, as you can imagine, this is kind of thinking about "B," "B" minus. It's,

0:24:59.009,0:25:02.730
yeah, there are some slightly more significant problems with your program.

0:25:02.730,0:25:05.130
But that's not where it ends, right, because we wanna

0:25:05.130,0:25:09.090
be able to even shoot for in some sense bigger gustoes. There was a plus

0:25:09.089,0:25:10.480
and a minus.

0:25:10.480,0:25:12.450
So plus is like,

0:25:12.450,0:25:15.660
oh, nice job, kind of a hearty

0:25:15.660,0:25:18.150
pat on the back. If you get

0:25:18.150,0:25:20.940
pluses all the way through on all your assignments, you're in a pretty good

0:25:20.940,0:25:22.539
candidate to get an "A" plus.

0:25:22.539,0:25:26.569
And minus, like, just take good over here and replace it with bad, it's kind of like,

0:25:26.569,0:25:28.250
oh,

0:25:28.250,0:25:31.730
bad times, right,

0:25:31.730,0:25:36.669
or maybe, you know - but

0:25:36.669,0:25:40.028
even there was, like, more significant problems with this program or just the

0:25:40.028,0:25:42.759
style on the program is just really bad.

0:25:42.759,0:25:46.879
But even there, we don't stop. And you're, like, "Come on, man. Like, I thought the whole reason

0:25:46.880,0:25:51.490
was to simplify this." Don't worry. And it gets even better because we have a plus-plus

0:25:51.490,0:25:55.599
and a minus-minus. And at this point, we've run out of board space, so we can't go any further.

0:25:55.599,0:25:57.009
But a plus-plus

0:25:57.009,0:25:59.249
is just outrageous,

0:25:59.249,0:26:02.409
right? It's the kind of thing - so this is the kind of thing your section leader can't

0:26:02.409,0:26:03.399
actually give you

0:26:03.398,0:26:05.679
without coming and talking to Ben and I first

0:26:05.680,0:26:09.480
because they get a program that just goes - it has to actually exceed the

0:26:09.480,0:26:11.860
requirements for the assignment. It's by a long shot.

0:26:11.859,0:26:14.758
Like, you'll get all your assignment requirements, and what we encourage you

0:26:14.759,0:26:18.429
to do is you can do a grade assignment and get everything right and have good style,

0:26:18.429,0:26:21.710
and you'll be in this category. And for the later assignments, you may be in this category if it's

0:26:21.710,0:26:22.390
flawless.

0:26:22.390,0:26:25.659
But we'll actually - if you want to go for the plus-plus,

0:26:25.659,0:26:28.740
go beyond the assignment requirements. And the way we think about the plus-plus, it's a

0:26:28.740,0:26:30.659
program that makes you weep

0:26:30.659,0:26:32.040
in a good way.

0:26:32.039,0:26:35.000
It's just like your section leader sees it, and they're just, like,

0:26:35.000,0:26:38.558
this is so good, I've gotta show someone else. And they come and show Ben and

0:26:38.558,0:26:42.470
I, and we're, like, sitting there looking at this on a monitor, and, like, tears are just welling in our eyes, and there was,

0:26:42.470,0:26:43.380
like,

0:26:43.380,0:26:46.810
soft violin music playing in the background and we get out the wine and

0:26:46.809,0:26:47.720
cheese.

0:26:47.720,0:26:52.880
So this is just, like, this is the kind of thing that gets you, like,

0:26:52.880,0:26:56.350
remembered and the, oh, if you want a letter of recommendation, just ask because you got

0:26:56.349,0:26:59.349
a plus-plus. Like, oh,

0:26:59.349,0:27:03.168
it's awesome, right? There are very few of these in a quarter. So just by sort of

0:27:03.169,0:27:06.460
way of comparison, in a class this size, probably throughout the span of the

0:27:06.460,0:27:09.950
whole quarter, I'd expect there to be maybe ten plus-pluses,

0:27:09.950,0:27:13.610
I mean, ten assignment plus-pluses, not ten students who get plus-pluses across the

0:27:13.609,0:27:13.959
board.

0:27:13.960,0:27:16.808
So it's really something to strive for, but if you strive for it,

0:27:16.808,0:27:20.599
like, we're giving you the credit for it. And this gets remembered and you get, like,

0:27:20.599,0:27:22.699
extra credit and everything.

0:27:22.700,0:27:25.019
So we're left with this,

0:27:25.019,0:27:29.849
right? This assignment also makes you weep,

0:27:29.849,0:27:33.309
but not in the good way, right? It makes you kind of weep in the sense, like, I look at

0:27:33.309,0:27:34.769
them and I'm, like,

0:27:34.769,0:27:39.319
oh, man, like, what did I teach? Like, where did I go wrong, right? I, like,

0:27:39.319,0:27:40.619
blame myself.

0:27:40.619,0:27:44.629
I blame you a little bit, but I blame myself.

0:27:44.630,0:27:47.450
And this is really just, like, the program is just, like, it's a

0:27:47.450,0:27:50.830
shell. Like, there really wasn't much effort that was put into it. Yeah, you slapped something together

0:27:50.829,0:27:53.139
or it doesn't really work,

0:27:53.140,0:27:56.030
that whole deal. And then if you don't turn anything in, we do kind of reserve the

0:27:56.029,0:27:58.579
zero to distinguish from the

0:27:58.579,0:28:02.720
"made really bad effort" versus "didn't make any effort at all."

0:28:02.720,0:28:06.410
And we just won't talk about these, right? Let's just hope we can avoid those

0:28:06.410,0:28:10.100
if possible. But that's kind of how the grading scale works now. Now,

0:28:10.099,0:28:13.859
at the same time, I trust all of you to be responsible people.

0:28:13.859,0:28:17.329
And every once in a while, something bad happens to a good person, and

0:28:17.329,0:28:20.558
there's an assignment that you'd like to be able to turn in, but for whatever reason, you

0:28:20.558,0:28:23.710
can't turn in on time. And I just wanna treat you like adults.

0:28:23.710,0:28:27.700
I don't want you to have to worry about coming in and asking for an extension

0:28:27.700,0:28:31.298
or, like, "Oh, I had this really hard thing in another class, and I couldn't do it at the same time." Up

0:28:31.298,0:28:32.109
front,

0:28:32.109,0:28:34.229
everyone gets two free extensions, okay? So

0:28:34.230,0:28:38.930
in terms of late days - we refer to these as late days, strangely enough - you

0:28:38.930,0:28:40.509
get two free ones.

0:28:40.509,0:28:44.440
What a late day is, is a class day. They're not 24-hour days, but class days.

0:28:44.440,0:28:48.059
So if something is due on a Wednesday, you turned in on a Friday, that's a late

0:28:48.059,0:28:49.059
day. That's one.

0:28:49.059,0:28:51.888
You turn it in on the following Monday, that's two late days.

0:28:51.888,0:28:54.599
You can split up your two late days among two different assignments. You can use

0:28:54.599,0:28:56.148
them both on one assignment.

0:28:56.148,0:28:59.819
But we encourage you to not use them at all because if you use your late days, you fall behind

0:28:59.819,0:29:00.868
in the class.

0:29:00.868,0:29:05.038
The way you should think about these things are these are pre-approved extensions.

0:29:05.038,0:29:08.190
They're not the kind of thing where you just think, "Oh, yeah, I'm not gonna do the

0:29:08.190,0:29:11.190
assignment because I wanna go and play Frisbee golf," right?

0:29:11.190,0:29:14.330
Think of it, well, you wouldn't come ask me for an extension - you might, but you probably wouldn't

0:29:14.329,0:29:17.619
ask me for an extension if you're, like, "Hey, hey, Mehran, can I turn in the

0:29:17.619,0:29:19.599
assignment, like, on Wednesday because

0:29:19.599,0:29:22.719
I'm playing Frisbee golf this afternoon," right? If you would feel embarrassed

0:29:22.720,0:29:25.798
asking that question, you probably don't wanna use one of your free late days.

0:29:25.798,0:29:27.460
But something happens like,

0:29:27.460,0:29:30.809
oh, it's a tough week, you've got midterms in other classes and you got this assignment

0:29:30.809,0:29:32.879
due or whatever, that's a good time to use it.

0:29:32.880,0:29:36.280
So we just trust you. And most people, we actually encourage you not to use them

0:29:36.279,0:29:39.170
because it just makes you fall behind in the class.

0:29:39.170,0:29:42.200
Because we trust you and we give you these two up front, getting extensions

0:29:42.200,0:29:45.809
beyond your two free class days is virtually impossible because we sort of

0:29:45.809,0:29:46.539
up front said,

0:29:46.539,0:29:49.210
hey, it's your responsibility. We're giving you two freebies.

0:29:49.210,0:29:52.470
We're not gonna give you a third extension. Imagine if you had to come ask us for three

0:29:52.470,0:29:55.539
extensions. By the third one, we'd be, like, okay, what's going on, which is why

0:29:55.539,0:29:57.710
we don't necessarily give extensions beyond these two.

0:29:57.710,0:30:00.858
The only time we might give an extension beyond the two free ones is for

0:30:00.858,0:30:02.149
something major, like

0:30:02.150,0:30:06.300
death in the family or, like, serious medical problems that might require surgery or

0:30:06.299,0:30:07.250
something like that.

0:30:07.250,0:30:10.349
Every once in a while, unfortunately, that happens. I hope it doesn't happen in this

0:30:10.349,0:30:10.738
class.

0:30:10.739,0:30:13.869
But those are the only kinds of things that we give extensions to beyond the two

0:30:13.868,0:30:15.058
free late days.

0:30:15.058,0:30:18.739
Importantly, don't ask your section leader for extensions. They cannot grant you

0:30:18.739,0:30:22.249
extensions. Only Ben, who has all the power in this class, can give extensions, which

0:30:22.249,0:30:25.308
is why you should get to know Ben and then hopefully you won't need to talk to him about

0:30:25.308,0:30:27.629
extensions, okay? So

0:30:27.630,0:30:31.610
other thing to keep in mind is that three days late is the max.

0:30:31.609,0:30:36.129
Beyond three days late, which is basically one class week, if you think

0:30:36.130,0:30:39.390
about late days being class days, we will not accept an assignment. And the reason

0:30:39.390,0:30:42.130
for that is at a certain point, you're so late, you're better off just doing the

0:30:42.130,0:30:44.120
next assignment, letting the old one go.

0:30:44.119,0:30:48.409
So to sort of enforce that policy, after three days, we don't accept that

0:30:48.410,0:30:51.259
assignment late anymore. It's just gonna be a zero if it's not turned in, okay?

0:30:51.259,0:30:53.200
And that just kind of forces you to keep up.

0:30:53.200,0:30:56.870
Couple other minor things, well, I shouldn't say they're minor things. They're actually kind of important. Exams: There's

0:30:56.869,0:30:59.539
two exams in this class. There's a midterm and a final.

0:30:59.539,0:31:04.259
Both of them are, well, I shouldn't say both. The midterm is out of class. It's

0:31:04.259,0:31:07.730
from 7:00 to 8:30 p.m.

0:31:07.730,0:31:13.250
on Tuesday, October 30. And it's on the syllabus. It's there. It's on the syllabus; it's

0:31:13.250,0:31:16.630
on Handout No. 1. We repeat it multiple times. The date will eventually be announced

0:31:16.630,0:31:18.019
when we get close to the midterm.

0:31:18.019,0:31:22.460
But if you have a conflict with this time, you need to send me email, okay?

0:31:22.460,0:31:26.670
You can send me email a little closer to the midterm because I'll announce it again for people who have

0:31:26.670,0:31:27.179
conflicts.

0:31:27.179,0:31:31.759
But since it's an out-of-class exam, you need to send me email if you have a conflict.

0:31:31.759,0:31:34.868
I'll get all the constraints from people who have conflicts and try to schedule an

0:31:34.868,0:31:36.808
alternate time if there's enough people with conflicts.

0:31:36.808,0:31:40.879
But 7:00 to 8:30 is when you need to know about the midterm. And to make up for

0:31:40.880,0:31:43.420
the fact that we have an out-of-class midterm, I actually give you sort of

0:31:43.420,0:31:46.769
a belated free day, which is the Friday of the week of the midterm, we don't have

0:31:46.769,0:31:50.109
class to make up for the fact that we made you come to the midterm outside of class.

0:31:50.109,0:31:53.308
But the midterm's an hour and a half, and we can't compress time. If we could, we'd

0:31:53.308,0:31:54.480
have different issues.

0:31:54.480,0:31:57.308
We can't compress time and fit it into a 50 minute class, which is why it's

0:31:57.308,0:31:59.399
out of class, but you get a free day for it,

0:31:59.400,0:32:01.750
all right? Last but not least,

0:32:01.750,0:32:03.970
few things about grading.

0:32:03.970,0:32:06.490
Grading, one of those things as you might be able to tell from this little board

0:32:06.490,0:32:09.620
over here or something, if I didn't have to do it, I wouldn't do it

0:32:09.619,0:32:13.779
because honestly, as corny as this sounds, I just believe in the love of learning.

0:32:13.779,0:32:16.549
Like, I think if you're passionate about something, you just go do it and you

0:32:16.549,0:32:17.629
learn it.

0:32:17.630,0:32:21.550
But I'm na?ve, and so that's not the way learning always works. So sometimes we

0:32:21.549,0:32:24.859
actually need grading to make sure that learning takes place. And so this is how your

0:32:24.859,0:32:26.378
grade breaks down:

0:32:26.378,0:32:30.759
Forty-five percent of your grade is on the programming assignments, okay?

0:32:30.759,0:32:34.740
Fifteen percent is the midterm, which we'll just call the mid because we like to

0:32:34.740,0:32:36.380
abbreviate everything.

0:32:36.380,0:32:41.019
Thirty percent is the final. It's a three-hour final exam in the regular final

0:32:41.019,0:32:42.528
time slot for this class.

0:32:42.528,0:32:45.619
If you think or are under the delusion that you should take two

0:32:45.619,0:32:47.269
classes at the same time,

0:32:47.269,0:32:50.269
that's a bad idea because their final exams are at the same time,

0:32:50.269,0:32:54.349
okay? So you should not take two classes as the same time

0:32:54.349,0:32:57.649
because our final exam is scheduled for - I believe it's December 13, which

0:32:57.650,0:32:58.080
is a

0:32:58.079,0:33:01.730
Thursday, 12:15 to 3:15. That's the regular final exam slot for

0:33:01.730,0:33:05.210
this class. And any other class at the same time will conflict with that slot. Thirty

0:33:05.210,0:33:08.559
percent of your grade is the final. And that, if you add it all up,

0:33:08.559,0:33:12.589
it's not just that I'm bad with math. It's because 10 percent of your grade is actually

0:33:12.589,0:33:16.129
participation. And this is things like

0:33:16.130,0:33:19.240
did you go to your interactive grading sessions? Did you regularly attend

0:33:19.240,0:33:22.740
section? Did you participate in section? Did you participate in class, right?

0:33:22.740,0:33:26.259
And so, in order to help you participate in class,

0:33:26.259,0:33:29.890
there's a little incentive to participate in class, which is sugar in the afternoon.

0:33:29.890,0:33:32.980
So someone raise their hand. All

0:33:32.980,0:33:35.769
right.

0:33:35.769,0:33:38.220
Yeah, sometimes I'm not a good shot. And this will tell you, if you're sitting in

0:33:38.220,0:33:43.309
the back of the room, I can't throw a Kit Kat back there because they're a little

0:33:43.309,0:33:44.599


0:33:44.599,0:33:45.278
too light. Oh, yeah, sorry.

0:33:45.278,0:33:49.278
If you sit in the back of the room, the roof prevents me from actually being able to hit

0:33:49.278,0:33:53.359
you. So if you want the food, come up. But if you ask questions in class,

0:33:53.359,0:33:56.769
hey, that's a good time. It's just a little way to be able to reward you for

0:33:56.769,0:33:58.440
actually participating in class

0:33:58.440,0:34:01.139
or to keep your blood sugar up if you need it, all right?

0:34:01.138,0:34:05.008
So that's participation. It's 10 percent of your grade, and as a matter of fact, at the end of the quarter, I ask

0:34:05.009,0:34:08.599
every one of your section leaders to actually tell me how much you participated in class, and

0:34:08.599,0:34:11.918
some of them just say, "Oh, this person was wonderful. They came every time. They participated.

0:34:11.918,0:34:13.128
It's just a great thing."

0:34:13.128,0:34:15.858
And that helps your grade out a lot, okay?

0:34:15.858,0:34:17.469
Now, the final thing,

0:34:17.469,0:34:18.969
and as you can kind of tell,

0:34:18.969,0:34:21.399
most of the time, I'm not the most serious person in the world. I just like

0:34:21.400,0:34:24.059
to have fun with things, and I think it's important for you to have fun with

0:34:24.059,0:34:24.958
things.

0:34:24.958,0:34:28.277
There is just one place where I get real serious, and it's one place where Stanford

0:34:28.277,0:34:29.728
gets real serious.

0:34:29.728,0:34:32.848
Anyone wanna guess what that is?

0:34:32.849,0:34:35.899
Plagiarism and the honor code. As a matter of fact, that's what we call a social. So we

0:34:35.898,0:34:38.989
had someone down here who got it and then a whole bunch of people who I don't

0:34:38.989,0:34:44.967
know, so we just spray. All right.

0:34:44.969,0:34:47.969
So the honor code,

0:34:47.969,0:34:50.369
in terms of the honor code, the

0:34:50.369,0:34:54.559
question comes up is what is the honor code all about, and how does that affect working

0:34:54.559,0:34:57.609
in groups and computer science, etc.?

0:34:57.608,0:35:00.058
Does that mean we shouldn't talk to each other?

0:35:00.059,0:35:03.989
No. The answer to all those is no, okay? If you look at Handout No. 4,

0:35:03.989,0:35:05.809
which is all about the honor code,

0:35:05.809,0:35:08.849
we encourage you to talk to each other. We encourage you to talk about concepts

0:35:08.849,0:35:12.110
in the class, talk about different strategies to problems, to think about

0:35:12.110,0:35:14.659
the ways that you could potentially approach some problem or

0:35:14.659,0:35:17.739
the way different control constructs when we eventually get to them work in the

0:35:17.739,0:35:20.659
class. And discussion is perfectly fine,

0:35:20.659,0:35:23.729
especially among the course staff, but also amongst yourselves. That's a great

0:35:23.728,0:35:24.578
thing.

0:35:24.579,0:35:28.359
So where do we draw the line? And we try to make a bright line for where you've

0:35:28.358,0:35:31.929
crossed the line for the honor code, which is

0:35:31.929,0:35:35.318
don't share code,

0:35:35.318,0:35:36.429
plain and simple,

0:35:36.429,0:35:38.450
in any respect, okay?

0:35:38.449,0:35:41.848
Don't give a file to someone else that's got your code in it. Don't get code

0:35:41.849,0:35:45.229
from someone else. Don't look at someone else's printout. Don't give them a

0:35:45.228,0:35:45.659
printout.

0:35:45.659,0:35:49.190
If you have two people who are sitting looking at the same screen together,

0:35:49.190,0:35:51.159
that code can't belong to both of you.

0:35:51.159,0:35:52.358
It belongs to one of you.

0:35:52.358,0:35:56.028
I don't know which one, but it becomes an honor code violation. So you shouldn't

0:35:56.028,0:35:59.059
both - two people shouldn't be staring at the monitor together.

0:35:59.059,0:36:02.829
If it ever gets to the point where you're looking at someone else's code, that's

0:36:02.829,0:36:05.228
where you're gonna reach an issue, okay?

0:36:05.228,0:36:07.408
Discuss as much as you want. That's great.

0:36:07.409,0:36:10.429
Write your own code. That's all we care about. And you're, like, "Well, what is

0:36:10.429,0:36:14.880
code, Mehran? What does that word mean?" Code is geek speak for your program,

0:36:14.880,0:36:18.079
so when you program, the program that you write is what we affectionately refer to

0:36:18.079,0:36:19.329
as code.

0:36:19.329,0:36:23.028
And the idea of programming is what we refer to as coding,

0:36:23.028,0:36:25.639
strangely enough. Computer scientists need to make everything

0:36:25.639,0:36:28.160
more complicated than it really is so we can

0:36:28.159,0:36:31.449
get people under the illusion that they should pay us lots of money to do what we do.

0:36:31.449,0:36:35.409
I mean, you're, like, "Oh, I just write programs." And they're, like, "Oh, yeah, I should pay you

0:36:35.409,0:36:38.348
half." And you're, like, "No, no, no. I write code." And they're, like, "Oh, yeah." Suddenly, it's much more

0:36:38.349,0:36:40.009
impressive. So

0:36:40.009,0:36:40.920
don't share code.

0:36:40.920,0:36:44.780
The other thing is if you talk to other people, like if you have a study group to

0:36:44.780,0:36:48.220
talk about solution approaches or you go, let's say, talk to the TA or your section

0:36:48.219,0:36:48.648
leader

0:36:48.648,0:36:51.318
to how you should approach a problem, and they give you a lot of hints as to how

0:36:51.318,0:36:52.739
to do it,

0:36:52.739,0:36:55.528
cite collaboration.

0:36:55.528,0:37:00.119
So cite and collaboration gets you out of trouble. Any collaboration that you cite

0:37:00.119,0:37:03.250
you cannot be held responsible for under the honor code.

0:37:03.250,0:37:06.949
You can actually copy someone else's program and say, "I copied this program

0:37:06.949,0:37:08.228
from Mary Smith."

0:37:08.228,0:37:09.748
And I'll look at that and say,

0:37:09.748,0:37:12.598
"They cited it," and it will warm the cockles of my heart.

0:37:12.599,0:37:15.769
And Mary Smith will get full credit, and you'll get a zero because you copied your

0:37:15.768,0:37:17.218
program from Mary Smith,

0:37:17.219,0:37:22.289
but it's not an honor code violation because you cited the work, okay? So

0:37:22.289,0:37:26.929
the bottom line is keep yourself safe and cite your collaborations. And I

0:37:26.929,0:37:29.450
guarantee you most of the time, you'll be just fine.

0:37:29.449,0:37:32.439
Now, you might wonder why do I make such a big deal about this. And the reason I

0:37:32.440,0:37:35.470
make a big deal about this is for a while, thankfully it's not true anymore, but

0:37:35.469,0:37:36.359
for a while,

0:37:36.360,0:37:39.890
the computer science department actually had more honor code violations than the

0:37:39.889,0:37:43.118
rest of the university combined.

0:37:43.119,0:37:45.519
Take everything else in the university, put them all together, they were like over

0:37:45.518,0:37:48.808
here. And we're, like, we're computer science,

0:37:48.809,0:37:52.450
which is not a fun distinction to have, let me tell you.

0:37:52.449,0:37:55.368
And you might wonder why is that? Is that because computer science people are just

0:37:55.369,0:37:58.028
mischievous and dishonest? No.

0:37:58.028,0:38:01.898
It's because it's easier to catch honor code violations in computer science. We have a

0:38:01.898,0:38:05.118
whole bunch of tools that allow us - then we take all your programs and we run them through

0:38:05.119,0:38:07.809
this tool, and it compares them not only to everyone else in here, but, like,

0:38:07.809,0:38:11.119
to everyone from the last, like, X years where X is the large number of people who've

0:38:11.119,0:38:13.209
ever gone through the classes, right?

0:38:13.208,0:38:16.588
And it's an extremely good tool from finding where honor code violations

0:38:16.588,0:38:17.029
happen,

0:38:17.030,0:38:18.909
from where they don't. And it

0:38:18.909,0:38:23.139
doesn't find spurious violations. To be honest, I've never lost an honor code

0:38:23.139,0:38:24.349
case. When I

0:38:24.349,0:38:26.480
find an honor code case,

0:38:26.480,0:38:27.630
it is blatant.

0:38:27.630,0:38:30.110
And you take it to judicial affairs, and they look at it, and they're, like,

0:38:30.110,0:38:31.269
yeah, this is blatant.

0:38:31.268,0:38:34.318
And I take it to the student, and every student I've ever confronted them

0:38:34.318,0:38:38.139
with never said, "No, no, no. I didn't cheat." They said, "You caught me," okay?

0:38:38.139,0:38:41.639
So it's blatant. It's not like, oh, there's some little line in it, "Oh, am I gonna need to

0:38:41.639,0:38:43.638
worry about an honor code violation?"

0:38:43.639,0:38:47.249
Remember those rules, you have nothing to worry about in this class. It's people who go and,

0:38:47.248,0:38:50.748
like, fish out printouts from the recycle bins and copy other people's

0:38:50.748,0:38:53.329
code that are the people we catch, right? It's blatant cheating

0:38:53.329,0:38:54.179
that we catch.

0:38:54.179,0:38:55.090
But we catch it.

0:38:55.090,0:38:59.298
We catch it all the time. So I hope, I pray it doesn't happen in this class.

0:38:59.298,0:39:02.038
But the reason I make a big deal about it is historically if I look at the

0:39:02.039,0:39:05.630
evidence, it happens and we catch it. And when we catch it, we're required by the

0:39:05.630,0:39:09.088
university to prosecute. And I feel bad because usually it's someone who just made a

0:39:09.088,0:39:10.179
bad call, like,

0:39:10.179,0:39:13.289
they were up way too late the night before working on something else, and

0:39:13.289,0:39:16.909
they're not thinking straight. And rather than just taking a late day or turning in their

0:39:16.909,0:39:19.608
assignment late and getting a slight penalty on it beyond their two free late

0:39:19.608,0:39:20.369
days,

0:39:20.369,0:39:23.470
they decide to cheat. And that's just always the wrong call, okay?

0:39:23.469,0:39:26.879
So you just don't wanna put yourself in that situation. So I get real serious

0:39:26.880,0:39:31.778
about it for a moment, and hopefully it won't be an issue and we can just kind of go on, okay?

0:39:31.778,0:39:35.088
So with that said, that's a whole bunch of logistical stuff.

0:39:35.088,0:39:38.108
Any questions about the logistics of this class or anything I just talked

0:39:38.108,0:39:42.929
about? Uh huh? You had briefly mentioned the late penalty.

0:39:42.929,0:39:44.410
Oh, the late penalty, good point.

0:39:44.409,0:39:46.399
So remember our little bucket scale.

0:39:46.400,0:39:50.349
If you go beyond your two free late days, every day you turn in an assignment late beyond

0:39:50.349,0:39:52.319
those, it drops down one bucket.

0:39:52.320,0:39:55.550
So let's say you already used your two free late days on Assignment No. 1. And on

0:39:55.550,0:39:58.310
Assignment No. 2, you turned in something one day late and you would have gotten a

0:39:58.309,0:40:00.179
check normally, it becomes a check minus.

0:40:00.179,0:40:06.108
So that's how it is. It's one bucket per late day beyond your two free ones. Uh huh? Are the sections first come, first served?

0:40:06.108,0:40:09.308
Yeah, the sign-ups, well, they take into consideration your preference, but

0:40:09.309,0:40:12.369
part of your preference is to do the match is first come, first served.

0:40:12.369,0:40:14.899
So you wanna sign up early.

0:40:14.898,0:40:15.778
Oh,

0:40:15.778,0:40:17.518
thanks for your honesty. As a matter of fact,

0:40:17.518,0:40:20.699
I dig honesty, all right?

0:40:20.699,0:40:23.679
Any other questions?

0:40:23.679,0:40:29.058
It's just honesty's cool. Uh huh? How much time should we plan on studying [inaudible]?

0:40:29.059,0:40:32.039
Oh, good question. How much time should you plan? And this is something that I say for

0:40:32.039,0:40:34.470
classes in general at Stanford, which is not always true,

0:40:34.469,0:40:37.559
which is take the number of units that a class is,

0:40:37.559,0:40:43.128
multiply it by three. That's how many hours you'll spend per week in that class, total,

0:40:43.128,0:40:44.230
on average.

0:40:44.230,0:40:47.719
So what that means is in 106A, a 5 unit class, you multiply by 3, you

0:40:47.719,0:40:49.029
get 15.

0:40:49.030,0:40:52.390
Five of those hours are roughly spent between class, section, interactive grading,

0:40:52.389,0:40:53.289
other stuff.

0:40:53.289,0:40:57.050
That means on average about ten hours a week will be spent on your assignments

0:40:57.050,0:40:58.310
in this class.

0:40:58.309,0:41:01.690
Again, that's an average. Sometimes when I go to computer science conferences, I sit there and joke

0:41:01.690,0:41:04.380
around with plans. And we're, like, "Oh, how long did your assignments take?"

0:41:04.380,0:41:07.619
And I say, "Oh, on average, ten hours." And what I really mean when I say on average 10

0:41:07.619,0:41:07.999
hours

0:41:07.998,0:41:10.858
is they take between 3 and 45,

0:41:10.858,0:41:14.058
okay? It's a large variance event, right?

0:41:14.059,0:41:17.439
Ten is the average. Some people take a really long time. Some people get through it

0:41:17.438,0:41:21.358
really quickly, but that's about the average you can plan for. Uh huh?

0:41:21.358,0:41:27.598
Another question? [Inaudible] late days [inaudible] class days?

0:41:27.599,0:41:32.009
Yeah, all late days are class days, so the free ones -

0:41:32.009,0:41:35.579
the halfway mark's really my reach. That's about it.

0:41:35.579,0:41:39.900
All right. So I do wanna give you your very beginning of an introduction to

0:41:39.900,0:41:42.778
programming before we sort of break for the day. How

0:41:42.778,0:41:45.880
are we doing on time?

0:41:45.880,0:41:49.108
And so in order to kind of see this,

0:41:49.108,0:41:51.739
there's a few things that we wanna keep in mind. Actually, let me show you a

0:41:51.739,0:41:54.989
little picture, okay?

0:41:54.989,0:41:56.829
Sometimes

0:41:56.829,0:41:59.239
when we talk about writing programs,

0:41:59.239,0:42:01.539
we talk about debugging programs,

0:42:01.539,0:42:04.728
right? How many people ever heard the term debugging or bugs in programs?

0:42:04.728,0:42:08.208
A bug in a program is an error in a program, so sometimes when you hear us

0:42:08.208,0:42:12.678
say, "Oh, come see," like, your section leader to help debug or see the helpers in LaIR.

0:42:12.679,0:42:16.039
That's another thing. In the Tresidder computer cluster is the LaIR.

0:42:16.039,0:42:18.579
It's a computer cluster that we have helpers there to help you get through

0:42:18.579,0:42:21.189
this class. What is it?

0:42:21.188,0:42:21.978
Sunday through

0:42:21.978,0:42:26.668
Thursday, every week, from around 2:00 in the afternoon 'til midnight every day, okay,

0:42:26.668,0:42:29.668
to help you get through the class. So that's a good place if, you know, you can

0:42:29.668,0:42:32.558
work in your dorm room certainly, but if you also want help, go to the Tresidder

0:42:32.559,0:42:36.149
computer cluster, and there will be helpers there. There's a little queue you sign up for

0:42:36.148,0:42:38.588
to get help, and that's a great place, and it's all explained in Handout

0:42:38.588,0:42:39.349
No. 1,

0:42:39.349,0:42:41.199
but that's just something to keep in mind.

0:42:41.199,0:42:44.509
Where the term debugging comes from, it turns out this is an apocryphal story, but I'll tell

0:42:44.509,0:42:45.429
you anyway.

0:42:45.429,0:42:48.679
Back in the days of yore, in 1945 actually, there was a computer called the

0:42:48.679,0:42:52.079
Mark II at Harvard. And there was a woman named Grace Murray Hopper. Anyone ever

0:42:52.079,0:42:54.168
heard of Grace Murray Hopper?

0:42:54.168,0:42:58.328
A few folks. She was actually the first woman who was an admiral in the navy.

0:42:58.329,0:43:01.859
And she was also one of the very early pioneers of computer programming. She did

0:43:01.858,0:43:05.068
a lot of computer programming when she was actually a captain, and she was stationed

0:43:05.068,0:43:08.829
at Harvard as part of some sort of navy thing. I don't know why, but that's what

0:43:08.829,0:43:09.440
happened.

0:43:09.440,0:43:12.039
And they had this huge computer there, and they were noticing the computer was

0:43:12.039,0:43:14.900
on the fritz, and they couldn't understand what was wrong. And this is one of these

0:43:14.900,0:43:17.970
big old machines in the days of yore that has vacuum tubes and stuff inside it.

0:43:17.969,0:43:21.079
So they walked inside the computer, right, because then you could actually open it up

0:43:21.079,0:43:23.009
and walk inside your computer.

0:43:23.009,0:43:25.248
And they saw this,

0:43:25.248,0:43:27.889
and I don't know if you can see that, but that's a moth.

0:43:27.889,0:43:31.858
It was a moth that had sort of given its life to be immortalized because it had actually

0:43:31.858,0:43:35.028
shorted out across two relays in the computer

0:43:35.028,0:43:36.579
and was causing these sort of

0:43:36.579,0:43:39.829
errors to happen on the fritz. And so they took the bug out, and once

0:43:39.829,0:43:43.380
they actually plucked this little charred bug out of there, the computer started

0:43:43.380,0:43:47.910
working fine again, and she taped it in her log book. And this log book's actually

0:43:47.909,0:43:51.588
preserved in the Smithsonian Institution now, which is where all this comes

0:43:51.588,0:43:54.529
from. Here's all the standard disclaimer information: "Image used under fair use for

0:43:54.530,0:43:58.079
education purposes. Use of this image is exempt from Creative Commons

0:43:58.079,0:43:59.880
and other licenses," just so you know.

0:43:59.880,0:44:02.039
Now the lawyers are happy.

0:44:02.039,0:44:06.119
But this is where we think of sort of the modern term debugging actually came from.

0:44:06.119,0:44:09.439
Now, it turns out the actual story is that the term debugging came from the

0:44:09.438,0:44:11.178
1800s, in the late 1800s

0:44:11.179,0:44:15.088
from mechanical devices. People actually referred to debugging as fixing mechanical

0:44:15.088,0:44:15.739
devices.

0:44:15.739,0:44:20.038
But this is kind of the apocryphal story for how it comes up in computer science. Now,

0:44:20.039,0:44:21.849
with that said,

0:44:21.849,0:44:25.109
what is the platform in which you're gonna sort of do your first debugging or

0:44:25.108,0:44:28.058
your first work on? We talked about Java, but in fact in this class, we're not

0:44:28.059,0:44:29.369
gonna start with Java.

0:44:29.369,0:44:32.778
We're gonna start with something even sort of simpler than Java because as I

0:44:32.778,0:44:36.259
mentioned, sometimes what happens in computer science is people learn all the features

0:44:36.259,0:44:39.748
of some language. And they think just knowing the language makes them a good

0:44:39.748,0:44:40.679
software engineer.

0:44:40.679,0:44:43.659
And they get so worried about all the features of the language

0:44:43.659,0:44:46.068
that they don't kind of think about the big picture.

0:44:46.068,0:44:49.259
And so there was a guy named Rich Pattis, who oddly enough was actually a grad

0:44:49.259,0:44:51.250
student at the time at

0:44:51.250,0:44:51.858
Stanford,

0:44:51.858,0:44:55.208
and he said, "You know what? If we're gonna teach computer science, when we first start out, why don't

0:44:55.208,0:44:58.599
we have people not worry about all of the different

0:44:58.599,0:45:00.779
commands of the language and all the different things they can do?

0:45:00.780,0:45:04.389
Let's start with something really simple so you can learn all the commands

0:45:04.389,0:45:08.169
real quick. And then you've mastered everything there is to master about that

0:45:08.168,0:45:11.708
language, and you can focus on the software engineering concepts." And it turns out to

0:45:11.708,0:45:15.048
be a brilliant idea, which has actually been adopted by a bunch of people.

0:45:15.048,0:45:19.409
And so Rich, who's a wonderfully friendly guy - sometime if we get him to

0:45:19.409,0:45:22.818
come to Stanford, I'll introduce you; he's just very nice -

0:45:22.818,0:45:27.318
came up with this thing called Karel the Robot. And

0:45:27.318,0:45:29.259
the term, "Karel"

0:45:29.259,0:45:31.748
actually comes from

0:45:31.748,0:45:36.308
Karel Capek.

0:45:36.309,0:45:40.039
Anyone know who he is? Oh, free candy. Uh huh? He coined the term,

0:45:40.039,0:45:42.949
"robot."

0:45:42.949,0:45:45.959
He coined the term, "robot." He was a Czech playwright who actually wrote a play

0:45:45.958,0:45:48.199
called, "RUR,"

0:45:48.199,0:45:52.409
which was about robots. And the word robot actually comes from a Czech word, the

0:45:52.409,0:45:53.969
Czech word for work.

0:45:53.969,0:45:57.940
And so the robot is named after

0:45:57.940,0:46:01.338
Karel. And some people say Karl, which is kind of actually closer to I believe if - I

0:46:01.338,0:46:03.969
don't know if there's anyone who speaks Czech in the room - but closer to the

0:46:03.969,0:46:06.439
actual pronunciation. But we say Karel these days because it's kind of like

0:46:06.440,0:46:07.909
gender neutral, okay?

0:46:07.909,0:46:09.869
And so Karel the Robot

0:46:09.869,0:46:13.318
is basically this robot that lives in a really simple world. And so I'll show you

0:46:13.318,0:46:16.289
all that you can meet Karel the Robot. He's friendly; he's fun.

0:46:16.289,0:46:18.588
I'll show you Karel the Robot.

0:46:18.588,0:46:21.239


0:46:21.239,0:46:25.969
So we gotta get Karel running. He's at the factory. He's getting souped up. We're energizing Karel.

0:46:25.969,0:46:29.418
You gotta add some color to it. Otherwise -

0:46:29.418,0:46:31.248
all right.

0:46:31.248,0:46:34.558
We're begging for him. Come on, Karel.

0:46:34.559,0:46:37.459
There he is. Oh,

0:46:37.458,0:46:41.538
yeah.

0:46:41.539,0:46:45.259
That's Karel the Robot. He looks like one of the old Macintoshes if you remember the original

0:46:45.259,0:46:48.289
Macintoshes that look like a lunch pail, except he's got legs.

0:46:48.289,0:46:51.788
One sticks out his back. That's just the way it is.

0:46:51.789,0:46:56.819
And the way Karel works is he lives in a grid. To you, it may not be exciting, but to

0:46:56.818,0:46:58.630
Karel, it's way exciting.

0:46:58.630,0:47:03.179
So Karel lives in this little grid, and the way the grid works is there are streets and

0:47:03.179,0:47:06.789
avenues in the grid. Streets run horizontally, so this is First Street,

0:47:06.789,0:47:08.430
Second Street, Third Street.

0:47:08.429,0:47:11.559
And then over here, we have avenues, First Avenue, Second Avenue, Third

0:47:11.559,0:47:14.750
Avenue, Fourth Avenue, Fifth Avenue. It's kind of like Karel lives in Manhattan if you wanna

0:47:14.750,0:47:16.338
think about it that way, okay?

0:47:16.338,0:47:19.748
So Karel always is on one of these corners. So right now, he's at the corner of

0:47:19.748,0:47:22.788
First Street and First Avenue, or we just refer to it as 1 1 if you wanna

0:47:22.789,0:47:25.130
think about sort of Cartesian coordinates, right? But

0:47:25.130,0:47:26.780
just think of them as streets and avenues.

0:47:26.780,0:47:28.609
That's where Karel lives.

0:47:28.608,0:47:32.278
And Karel can move around in this world. There's a bunch of things that Karel can do.

0:47:32.278,0:47:33.889
He can take steps forward.

0:47:33.889,0:47:36.939
He can turn around to face different directions, and he can sense certain

0:47:36.938,0:47:38.288
things about his world.

0:47:38.289,0:47:41.400
So there's some things that exist in Karel's world, okay?

0:47:41.400,0:47:45.340
Things like walls that Karel cannot move through, right, so his world has

0:47:45.340,0:47:48.740
walls all around it that he can't go through, so he can't fall off the end of the

0:47:48.739,0:47:49.139
world.

0:47:49.139,0:47:52.629
And there's other walls like this one if Karel were over here, he can't step through

0:47:52.630,0:47:54.169
that wall.

0:47:54.168,0:47:57.768
There's also something referred to as beepers in Karel's world. And what a

0:47:57.768,0:48:00.488
beeper is, is it's like a big diamond,

0:48:00.489,0:48:03.909
okay? But what a beeper really is, is basically just some marker that he puts in

0:48:03.909,0:48:06.510
the world. You can think of a beeper like a piece of candy.

0:48:06.510,0:48:10.530
And Karel just goes around, like, putting pieces of candy in the world. As a matter of fact, not

0:48:10.530,0:48:12.999
only does he put pieces of candy in the world,

0:48:12.998,0:48:17.948
he carries around a whole bag of candy. So he has a beeper bag with him, and

0:48:17.949,0:48:21.099
sometimes that bag has a whole bunch of beepers in it; sometimes it only has one

0:48:21.099,0:48:22.318
beeper; sometimes,

0:48:22.318,0:48:25.998
it's sad Karel, and he has no beepers. But he's still got the bag.

0:48:25.998,0:48:28.798
There just don't happen to be any beepers in it. So he can potentially, if he

0:48:28.798,0:48:32.628
come across a beeper in his world, he can pick it up and put it in his bag,

0:48:32.628,0:48:35.509
or he can take, if he's got beepers in his bag, he can take them out of his bag

0:48:35.509,0:48:37.340
and put them places in the world.

0:48:37.340,0:48:40.860
And corners in the world can have either zero - if they have no beepers, they just appear

0:48:40.860,0:48:41.920
like a little dot -

0:48:41.920,0:48:44.059
or one or more beepers

0:48:44.059,0:48:47.199
on them that Karel can potentially pick up, okay?

0:48:47.199,0:48:51.229
So any questions about beepers or Karel having a little bag of beepers?

0:48:51.228,0:48:52.338
And that's it.

0:48:52.338,0:48:53.929
That's Karel.

0:48:53.929,0:48:57.298
That's his world. His world, we can make it larger if we want. We can put in walls in

0:48:57.298,0:49:00.219
different places. We can put beepers in different places. We can have Karel be in a

0:49:00.219,0:49:01.278
different place.

0:49:01.278,0:49:04.938
But starting next time, what you're gonna realize is with this extremely simple world,

0:49:04.938,0:49:08.558
there's actually some complicated things you can do. And after about a week - so

0:49:08.559,0:49:11.939
this first week, we're gonna focus on Karel - you'll notice that Karel is

0:49:11.938,0:49:15.658
actually a very nice, gentle introduction into Java. And a lot of the concepts that

0:49:15.659,0:49:20.148
we learn, sort of software engineering concepts using Karel, will translate over to the

0:49:20.148,0:49:21.969
Java world, okay?

0:49:21.969,0:49:25.338
So any questions about Karel or any of the other logistics that you've actually

0:49:25.338,0:49:28.599
heard about in the class?

0:49:28.599,0:49:33.619
Alrighty then. Welcome to 106A. I'll see you on Wednesday.