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‫Welcome back.

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‫In this video, we're going to have a look at the while loop.

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‫So first of all, the syntax, we start off with the counter and I'm going to set that to zero.

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‫Then we use the term while and in parentheses we have the condition.

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‫And in this case, I'm just going to say counter lower than ten.

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‫And if that's true, then run the code within the Y loop.

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‫So first of all, increment the counter just to be sure.

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‫And now we can go ahead and write our code.

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‫So console dot right line and I'm just going to print out the counter.

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‫So for now, nothing too fancy.

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‫And finally, we need to use console or read here to see what was written onto the console so that we

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‫are simple syntax pretty much the same as the do except for the while is now at the top and not at the

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‫bottom.

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‫And as you can see, zero through nine is printed onto the console.

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‫So this one checks first different than the do while loop which didn't check first, just ran the code

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‫to while loop checks first before it does anything.

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‫Now as you see, this is very similar but you can go ahead and build your own while loops now.

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‫All right now a little challenge for you.

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‫Please go ahead and write a little program in which the user can press enter and the number is increased.

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‫So it's written onto the console how high the number is.

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‫So let's say we have a counter of people and we want to count how many people have entered the bus.

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‫So let's say you are a teacher and now you want to make sure that you have all your students with you.

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‫So if you're a little people counter and that's exactly what we want to have here.

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‫So each time you press enter with no entry.

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‫So when it's empty, then go ahead if something else is written in there.

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‫So for example, an A or a letter or a anything else rather than an empty string, then go ahead and

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‫run the code again.

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‫So increase the number by one and until the user enters anything.

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‫So pretty much just a simple people counter.

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‫And once the user enter something, the people counter will just show, okay, everybody is in the bus

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‫and we're good to go.

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‫Okay.

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‫I hope you try to build that.

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‫What we need is a string and I'm going to call that one entered text and I'm going to set that to an

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‫empty string for now.

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‫And instead of checking the counter here, what I do is I check if enter text equals an empty string.

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‫And if that's true, I want to write something like please press enter to increase amount by one and

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‫anything else, plus enter if you want to finish counting.

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‫All right.

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‫So that's pretty much what's going to be printed onto the console.

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‫And by the way, we also want to see how many students we have currently inside of our bus.

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‫Current people count is.

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‫And then here's something that we haven't seen yet or we haven't used yet.

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‫And what that will do is it will simply replace this.

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‫Curly brackets, zero with the value of the counter.

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‫So we haven't used that yet, but that's how you can manipulate your strings a little bit.

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‫And so far what we have done was to use concatenation.

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‫So we used plus and then the counter, but that's actually a neater way to do that.

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‫All right.

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‫So let's check that actually, we need to read what the user has entered.

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‫So console the read line and we need to store that in entered text.

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‫All righty.

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‫So now let's check if our little program does what it should.

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‫So I'm going to press enter.

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‫Current people count as one, enter, two, three, four, and so forth.

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‫And once I press anything else, okay, or I enter anything else.

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‫For example, K enter current people count is 21 and now I close my program.

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‫By the way, what we can write here as well is to tell the user how many people there are.

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‫So right line curly brackets, zero.

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‫And here is the counter and a little text that I want to write is are inside the bus.

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‫People are inside the bus.

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‫Press enter to close the program.

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‫All right.

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‫And that's it.

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‫So let's run it again.

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‫And we have our little program here, our people counter.

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‫Please press enter to increase the amount by one.

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‫Let's do that.

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‫All right.

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‫And now let's.

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‫Press anything else w you current people count is six.

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‫Six people are inside the bus.

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‫Please enter to close or press enter to close the program.

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‫Pressing enter.

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‫That's done.

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‫So now you see how you can already build small programs which actually have a value.

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‫I know you can't simply reproduce that into an app, for example, where it would make more sense.

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‫But you have the core principles right here, so you just need user input and then you can use your

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‫code to run that.

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‫Great.

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‫So in the next video, we are going to have a little different challenge.

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‫So go ahead and try to solve that and see you in the next video.