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Welcome back.

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Before we go to the follow-up, I wanted to show you another application of the while loop because it

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will make it a little more clear what the differences and when to use what.

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So, for example, the for loop is really there to iterate through ranges, arrays and so forth, and

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we will see what that means in the next video.

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But before we do so, we will have to look at while loops which are great to execute a block of called

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repeatedly as long as the condition is met, as we saw earlier.

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So let's have an example where we don't look at numbers because so far we only looked at numbers.

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We said, OK, var x.

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As long as this white, then do something.

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But now let's say we have the situation where we have a variable called felt temperature and that one

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will be called.

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So let's say we are in the room and it feels like it's cold.

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So we don't know directly what temperature it is in terms of degrees, right, in terms of degrees Celsius.

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So we have also a value called room temperature, which actually is that value.

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So let's say 10 degrees.

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And.

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Now we will run a wild loop, which will increase the temperature, the room temperature by one degree

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until it's warm enough, so that felt temperature is not cold anymore.

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So here we are, just going to say as long as felts temp is cold, please run this wire loop, which

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will, as I said, increase the room temperature.

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So now, of course, we still need a situation where this condition is not met anymore, so we need

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to create this situation so we can check if the room temperature is greater or equal.

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20.

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Then set a felt temperature, too comfy, so too comfortable, so it's not going to be cold anymore.

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And also print something onto the console, parental and.

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It's comfy now.

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So now if we execute this.

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It will just print its comfy now.

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Why is that what happened in this whole thing?

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Well, we set the felt temperature too cold because when it's 10 degrees Celsius, then it's pretty

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cold and you don't want to be in the room when it's that cold.

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You want it to be 20 degrees Celsius.

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Which is sixty eight degrees Fahrenheit.

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All right, so what you say is as long as it's called, please turn up the heat, so increase the room

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temperature by one.

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And as soon as the room temperature hits 20 degrees.

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Then set the false temperature too comfy.

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So now in the room, we feel like all right is comfy, it's a good temperature.

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We can maybe even get rid of our jacket and then we can print.

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It's comfy now.

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And our while loop will stop, so at that point, our while loop will not increase the room temperature

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anymore and it will jump out of this whole loop and execute whatever comes afterwards.

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So this is just another application where you see that it doesn't have to be an integer that we're checking

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here.

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It can be whatever condition that has to be met.

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And as soon as this condition is not only met anymore, the while loop will stop executing its block

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here, its body, it's called block.