Name: CS50 2019 - リーディング8 - 情報 (CS50 2019 - Lecture 8 - Information)
Uploaded: 2021-01-14T10:21:02.000Z
Duration: 51 min 39 s
Description: VoiceTubeの動画で発音を聞きながら英語表現を覚えよう！学べる英語：

And just eight weeks ago, 2/3 of you had never

And what we thought we'd begin with today is really a look back of truly

how far you've come over just those several weeks.

In fact, it was just eight weeks ago when you first

started tinkering with Scratch, this graphical programming language

by which you could drag and drop puzzle pieces and make the computer

And then a week later, you might have struggled

with just getting Mario to ascend a pyramid by way of hashes

Which at the time was perhaps quite non obvious,

And then the week after that, you explored cryptography

And you learned how to encrypt and you decrypted information,

After that, you explored some electoral processes and the implementation

of algorithms that you might be familiar with from the real world, but perhaps

didn't think about the trade offs in choosing one algorithm or another.

And then ultimately, implementing it in code.

Just a week later did we transition to filters on Instagram,

implementing things like your own sepia filters.

So that moving forward, hopefully, you won't

take for granted when you click that button on the screen on your phone,

you actually know or can presume, or infer,

what's going on underneath the hood as it changes from one setting to another.

And then, of course, Big Board, where we handed you some 140,000 English words

And you had to implement your own spell check,

or a dictionary so to speak, with using as little amount of time

and as little space as you could, implementing ultimately your own hash

Thankfully since then, we can now take for granted that those things exist.

But you, indeed, built that from scratch.

Just a week later, we started handing you large files like this.

And of all things, you were able to deduce by writing some Python code

that this is lavender's DNA, among others

And then most recently, or perhaps quite soon,

when you learn to apply another language.

To questions like who has starred in films with Kevin Bacon.

And so, a number of tools are now in your toolkit.

And again, I would just emphasize that eight weeks ago, 2/3 of you

So even if it's felt like it has never let up

and each week feels all the more challenging than the last,

Consider what we promised in the first week of the class.

That what ultimately matters in this course

is not so much where you end up relative to your classmates,

but where you end up relative to yourself when you began.

And it is, indeed, those eight weeks ago that you began.

And it's today and in the courses final weeks that you will ultimately

So in trying to think today about what we hope your own takeaways are from,

not only the course, but computer science more generally,

I actually pulled up some of my own notes.

You might recall from week zero that I mentioned I took this course myself

back in 1996 and it happened to be the one that turned me from a government

And I didn't take many notes at first, it seems in that first class.

And so, I started flipping through these and in fact,

And if you focus on what's up here at the top, apparently, one of my first

notes to myself that a function, for those unfamiliar today,

And indeed, if I looked down further on my notes, arguments

It's info that's passed from one function to another

to have something done by or performed on it.

So that actually maps wonderfully cleanly to what

it is we indeed started ourselves doing those eight weeks ago.

Just talking about what CS is, problem solving.

And a problem is just something that's got input.

And the goal, of course, is to produce something with output.

And we had to agree from that very first week

how we're going to represent these inputs and outputs.

And so, we might do it symbolically with letters of the alphabet.

We know since then with that we might do it numerically as with decimal digits

or below that, we might just use binary, a different base

Or we could even represent that same capital A just using

some pattern of light bulbs or switches that you turn on in some order.

In fact, if you think back then to these first principles

that we introduced those weeks ago, to any of the students

Well, we just agreed weeks ago on what numbers map to what letters.

And so as long as all of the humans in the world

字幕リスト動画再生

CS50 2019 - リーディング8 - 情報 (CS50 2019 - Lecture 8 - Information)

ultimately

apparently

instance

audience