Original subtitles

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All right guys, it's time for your final coding exercise.

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So click on day 1.4 variables.

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Now the aim of the game is to switch the values of these two variables around.

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So if we go ahead and run our code as it is,

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it's going to ask us for a value of a. Let's call it five.

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And then it's going to ask us a value for b. Let's call that a hundred.

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And then when I hit enter,

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what you want the code to do is to go ahead and print a equals 100 and b equals

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five.

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So, basically switch those values around. And you're going to have to write your

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code in here. And it's really,

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really important that you don't change any of the code here or the code here.

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Now it's easy enough to simply just write print a equals b and b equals a.

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But this doesn't test you on anything. This is not the solution.

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This is wrong. Don't change the code here, don't change the code here.

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Instead, all

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you have are these lines where you can write as much code or as little code as

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you need to achieve this end. And when you achieve it,

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it should look something like this.

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You type a value for a, you type a value for b. And when you hit enter,

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they get printed out,

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but switched around. Have a think about how variables work,

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how they store data. And if you get really stuck,

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imagine that you have two cups; one holds a cup of milk, one

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holds a cup of coffee,

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and you wanna switch the contents of the cup around. How would you do that in

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real life? And then try and see if you can apply that logic to the code.

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Pause the video now and give this a go.

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All right. So I hope you didn't cheat

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and instead you actually had a think about this problem. If you got stuck,

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remember how I said

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if you have a cup of coffee and you have a cup of milk and you wanna switch the

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contents of the cups around, how would you do this in real life? Well,

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you would probably get a third cup, right?

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And then you'd be able to shift the contents around.

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So that's exactly what we're going to do with our code as well.

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We can create a new variable called c and we can set that to equal the value that's

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stored inside a. And then later on,

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we can get the variable a to store the value that's currently inside b.

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And finally,

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we're now ready to get b to store the value that was previously inside a,

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which is now contained inside the variable c. These three lines achieve this

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little switch rule that we've got here.

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And this is one of the most common Programming interview questions that you will

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come across. And the code is super simple,

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but what you have to apply here is some logic.

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And I usually think about real life examples

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like the cups and I hope that helped you as well.

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If this was at all confusing,

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then have a go at trying this out in Thonny.

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But if you got it right, then congratulations.

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This was actually quite a hard challenge.

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You had to think about a lot of things and think outside the box as well.

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So give yourself a pat on the back if you've got it right.

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If you didn't get it right,

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then I really recommend to put this code inside Thonny and see how it's being

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moved around so that you really,

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really understand what's going on behind the scenes.

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And then you can move on to the next lesson where we're going to talk about some

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of the rules around naming variables. For all of that

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and more, I'll see you there.