斯坦福106a是什么课

this presentation is delivered by the stanford center for professional development so welcome to cs one o six a， if you don't think you should be in cs one o six a you should think you should be somewhere different now it's probably a good time to to go not that i would scourge anyone taking this class think we'll have a lovely time in here but at this class is c s one or six a， so if you or e seventy a， so if you're like wait i thought i was in e seventy eight you're fine there are the same classes the same thing no worries okay there's four handouts there in the back if you haven't already gotten the handouts because you came in you sat down don't where you can pick them up on the way out there the same handouts they'll still be there so just a quick introduction that's what the first four handouts actually give you they give you a little bit of an introduction to the class what we're going to cover some of the logistics for the class and some other stuff we're going to go over all that today， so we can sort of get a good idea for where we're at okay， so just a quick show of hands before we get into a bunch of things in the class this is kind of an intro programming course them at it well， it is i should say it's kind of an intro programming course it is an intro programming course and it's always good to get an idea as to how much familiarity you may have beforehand okay， so just quick show of hands how many people can recognize a computer that's on sometimes when we talk about writing programs we talk about debugging programs how many people ever heard or at the term debugging or bugs in programs a bug in a program is an error in a program so sometimes when you hear us say oh come see like your section leader to help debug or see the helpers in layer that's another thing on the trusted or computer cluster is the layer it's a computer cluster that we have helpers there to help you get through this class or what is it sunday through thursday every week from around two in the afternoon till midnight every day okay to help you get through the class so that's a good place if you know you can work in your dorm room certainly， but if you also want help go to the trusted or computer cluster and there will be helpers there， there's a little queue you sign up for to get help and that's a great place and it's all explained in hand out number one， but that's just something to keep in mind where the term debug and comes from it turns out this is an apocryphal story but i'll tell you anyway back in the days of yore in nineteen forty five action i was a computer called the mark too at harvard and there was a woman named grace murray， hopper anyone ever heard of of grace murray， hopper a few folks she was actually the first woman who was an admiral and the navy and she was also one of the very early pioneers of computer programming she did a lot of computer programming when she was actually a captain and she was stationed at harvard as part of some sort of navy thing i don't know why but that's what happens and they had this huge computer there， and they were noticing the computer was on the fritz and they couldn't understand what was wrong and this is one of those big old machines in the days of your that has vacuum tubes and stuff inside it so they walked inside the computer right， because then you could actually open it up and walk inside your computer and they saw this and i don't know if you can see that， but that's a moth it was a moth that had sort of given its life to be immortalized because it actually shorted out across two relays in the computer and was causing these sort of you know errors to happen on the fritz and so they took the bug out and once they actually pluck this little charred bug out of there the computer started working fine again and she taped it in her log book and those log books actually preserved in the smithsonian institution now， which is where all this comes from here is all the standard disclaimer information image use under fair use for education purposes use of this images because it exempt from creative commons and other licenses just so you know now the lawyers are happy but this is where we think of sort of the modern term debugging actually came from now it turns out the actual stories that the term debugging came from the eighteen hundreds and the late eighteen hundreds from mechanical devices people actually refer to debugging as fixing mechanical devices， but this is kind of the apocryphal story for how it comes up in computer science now with that said what is the platform in which you're gonna sort of do your first debugging or your first work on we talked about java but in fact in this class we're not gonna start with java we're gonna start with something even sort of simpler than java because as i i mentioned sometimes what happens in computer science is people learn all the features of some language and they think just knowing the language makes them a good software engineer and they get so worried about all the features of the language that they don't kind of think about the big picture and so there was a guy named rich paddas who oddly enough was actually a grad student at the time at stanford and he said you know what if we're gonna teach computer science when we first start out why don't we have people not worry about all of the different commands of the language and all the different things they can do let's start with something really simple so you can learn all the commands real quick and then you've mastered everything there is to master about that language and you can focus on the software engineering concept and it turns out to be a brilliant idea which has actually been adopted by bunch people and so rich who's a wonderfully friendly guy sometime if we get him to come to stand for it all introduced you is just very nice came up with this thing called carol the robot and the term carol actually comes from carol chopek anyone know who he is oh free candy huh he coined the term robot he was a check playwright who actually wrote a play called r u r which was about robots and the word robot actually comes from a check word the check word for work and so the robot is named after carol and some people say carl which is kind of actually closer do i believe if i don't know if there's anyone who speaks check in the room but closer to the actual pronunciation but we say carol these days because it's kind of like gender neutral okay and so carol the robot is basically this robot that lives in a really simple world and so i'll show you you can meet carol robot he's friendly he's fun i'll show you carol the robot so we got to get carol running he's at the factory he's getting souped up we're energizing carol， doo doo doo you gotta add some color to it otherwise all right， we're begging for him come on carol there， he is yeah as carol the robot he looks like one of the old macintoshes if you remember the original macintosh doesn't look like a lunch pail except he's got legs one sticks out his back that's just the way it is and the way carol works is he lives in a grid to you it may not be exciting but to carol it's way exciting so carol lives in this little grid and the way the grid works is they're streets and avenues in the grids streets run horizontally， so this is first street， second street， third street， and then over here， we have avenues， first avenue， second avenue， third avenue， fourth avenue， fifth avenue it's kind of like carol lives in manhattan if you want to think about it that way so carol always is on one of these corners so right now he's at the corner first street in first avenue we just refer to as one one if you want to think about sort of cartesian coordinates right， but just think of him as streets and avenues that's where carol lives and carol can move around in this world there's a bunch of things that carol can do he can take steps forward he can turn around to face different directions and he can sense certain things about his world so there's some things that exist in carol's world okay things like walls the carol cannot move through right， so his world has walls all around it that he can't go through so there you know he can't fall off the end of the world and there's other world walls like this one if carol were over here he can't step through that wall there's also something referred to as beepers in carol's world and what a beeper is is it's like a big diamond okay but what a beeper really is is basically just some marker that he puts in the world you could think of a beeper like a piece of candy and carol just goes around like putting pieces of candy in the world as a matter of fact not only does he put pieces of candy in the world he carries around a whole bag a candy so he has a beeper bag with him and sometimes that bag has a whole bunch of beepers and it's sometimes it only has one beeper sometimes it's sad carol and he has no beepers but he still got the bag there just don't happen to be any beepers and it's so he can potentially if he comes across a beeper in his world he can pick it up and put it in his bag or you can take if he's got beepers in his bag you can take him out of his bag and put him places in the world and corners in the world can have either zero if they have no beepers they just appear like a little dot or one or more beepers on them that carol can potentially pick up okay so any questions about beepers or carol having a little bag of beepers and that's it that's carol that's his world his world we can make it larger if we want we can put in walls in different places we can put beepers in different places we can have carol be in a different place but starting next time what you're going to realize is with this extremely simple world there's actually some complicated things you can do and after about a week so this first week we're going to focus on carol you'll notice that carol is actually a very nice gentle introduction into java and a lot of the concepts that we learn sort of software engineering concepts using carol will translate over to the java world okay， so any questions about carol or any of the other logistics that you've actually heard about in the class already then welcome to one of six sales see you on wednesday。