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Hello, everybody, how are you?

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Now, we have completed the Four Loops series and we have seen lots of examples, I think that we are

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ready to study its twin brother in for loops.

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We have seen statements which helped us to sort of lead the code inside in Eve or inside itself.

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And we were scanning lots of variables or collections with the hand of the for loop and applying some

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actions upon the cells of a collection.

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So while LOOP is a bit different, let's start from the top and see the difference between the two loops.

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All right.

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So a take Python programming language repeatedly executes the code inside it as long as a given condition

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is true.

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So you can see right here that we have sort of condition once we declare while we didn't have it in

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for info Oprah just mentioned, what do we want to scan?

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For example, we have a list or we have a range, meaning we have certain number one, certain times

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the loop that will run.

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But we didn't have any condition, like practically we didn't could not declare a certain condition

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that we want.

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So in wireless, we do have it.

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So let's see quickly the differences between for and while loops.

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So we have seen that for loops we're scanning in sort of speak collections or variables one by one.

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Then after we were focused on a certain cell or some other variable, we added and if statement that

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could apply the upon the code inside the for loop, we had an if statement and each cell in our examples,

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we could determine what to do with it, like whether we want this element to apply a certain action

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or simply go to else and do not apply any action.

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So we had an, if else, statements inside the follow up.

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This is what helped us to navigate the code inside the for loop in while loops.

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It's a bit different in Y loops.

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We mention a condition right where we declare the loop.

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OK, so once we declare that we have a wire loop, we have a wire loop right there in the same line,

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we declare a certain condition what we didn't have in for loops in four follow ups.

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We had some conditions, some statements inside the fall.

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But right here in while loops, we declare a condition right where we declare the loop itself.

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And as long as the condition is true.

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We will keep running cycles upon the fire, upon the wire.

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What that basically means, we'll have cycles going again and again as long as this condition is true,

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OK?

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We've seen examples and example in a few seconds.

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OK, so the simplest way we can create a variable, just simply create a variable and you can call it

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no equals zero.

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This will work as our counter, basically.

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In other words, this will be the condition that we will check in every cycle of the wild.

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OK, so then we define a wire loop with a condition.

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The condition is the following thing.

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As long as no is smaller than 10, continue running.

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OK, so the beginning number equals zero equals zero.

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You can see where my mouth is.

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So number equals zero.

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Then we declare here a while.

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This is the key word for a while loops and then we set the condition in our in our example, it's no

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smaller than ten, but for now number equals zero zero.

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And if we run this cycle, this while loop again and again without growing our number, a variable number,

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if it's just stays zero.

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So it's an endless loop and can cause lots of trouble for our programmers, for programmers, whether

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they're web developers or back in front, it doesn't matter.

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Once you have an endless loop, it gets stuck in the whole system.

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Your whole computer or your server can break down because you had an endless loop and can crash your

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systems.

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All right.

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So we can't have this we can't have an endless loop in our code.

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And what we are willing to do, you can see the dots part right here.

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OK, so right here at the bottom, we have no plus equals one.

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OK, number plus equals one.

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What that means is what that means is, is basically this thing the same thing number equals number

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plus one.

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What you seen in the in the here in the example, in the code example the number equals the number of

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plus equals one is just a short way to write this thing.

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OK, number what we have current value growth by one.

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OK, so just going to erase it.

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So what we want to do.

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OK, ok.

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This part with a dot, it's inside the wire loop so each time the will run this call in the dots will

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be executed.

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So basically what we're saying here is each time you run the cycle, grow the variable number by plus

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one.

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So we start with this with zero and we get here.

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Here we're seeing growing by one.

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Then we go to the top again to the wild condition.

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OK, now the number, the variable here, it doesn't equal zero like we're declaring it.

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No, we have grabbed it by one right here at the bottom.

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So right now, number equals one already.

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So we execute the code again and again.

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Again and again.

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Up until the fall of the wild condition here would be false.

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Or in other words, as long as it's true, it will run again.

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So once we get here to 10, once we have here nine plus one and we go again to the top on the 10th cycle.

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So we'll have your number smaller than ten, which is ten, smaller than 10 once.

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This statement will be false.

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It would be a light.

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The code will exec exit the wire loop and go with the flow of code.

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What we have after the wild, it will exit the wild completely.

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So just want to just want a market once the value here would be ten.

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OK, this would be a false statement and then while Loop will be exited.

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All right.

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So that's it.

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It's plain.

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Simple.

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It's not very hard.

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Once you understood the four loops, this is piece of cake.

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You just have here a condition.

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You can set it here, whatever you want, whether a number or a letter or doesn't matter.

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And as long as this statement right here is through the cycle, what under the wire loop will keep running

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again, as will go from the top again and check the condition and run to the bottom and then again from

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the top and so on and so on.

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And you have to find a way to stop the while loop so it will not run forever.

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And this you do by changing variables inside the content of your while loop.

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So that's the theoretical sketch, for example, for for a second to see what we just seen here.

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So basically just start the module with a while.

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For example, you have a certain module that you have only a while openside.

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So you start running the module and then you get to a condition of.

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That while loop in this condition, we check if the statement is true, they called on their while loop

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will run and then you go again to the condition to the top.

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Then again, the condition is checked.

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If it's true, it will run again.

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OK, up until the condition would be false.

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Once the condition on the top would be false, the cold will exit your wirewood.

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That's it.

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Plain, simple.

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I think this theory covered the basics of a wild pretty easily.

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And you can see an example here to apply the rules.

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As we just discussed, we will go further to the next lecture by seeing advanced dance characters off

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while loops and also live examples as well.

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And right after we go to the practice part, I don't worry about it because it's pretty easy to understand.

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Once you once you get once you get the rule here and this is just mentioned, you will see many examples

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in the next lectures.

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And I think that you could get the hang of it.

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I'm sure of it.

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And that's about it.

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I think we closed up this lecture the next one.

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Thank you and bye bye.