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How's everybody doing, OK?

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I think it's time to begin giving you the answers of the homework once you tried to get the answers

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about yourselves.

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If you get into trouble, I'll just you want to verify your results.

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You can use this lecture to do it.

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OK, so first of all, create a new file, you can call it while loops practice.

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And from here, let's begin.

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So, first of all, let's add and comment here.

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Let's call it while loops practice.

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And as you recall, you have bought a Barbie and PERTZYE.

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All right, like this and first thing first, you were asked to create a list in poverty and use it

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along the way, the items were five, six, twenty four, thirty to twenty one and seventy.

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Right.

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And also, we need to put some spaces here.

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So Python would not be angry at us.

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All right.

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Like this.

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It's nice and beautiful.

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And from here, let us create our first wire loop of a OK.

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And right here we want to ages to be tested.

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And our stop condition is as long as ages is smaller than 30, we should continue on.

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All right.

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But in this way, we we don't actually test these cells.

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So how can we actually extract the cells out of the out of the list?

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All right.

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So we need to combine some knowledge out of the lists, lectures that we have seen.

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And the only way to extract values out of the list is using an index.

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Right.

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Like doing something like this.

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OK, so this is the way to extract values.

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So we need somehow to put out a way to enter some parameter here so we could extract values by index.

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And if we put, for example, a simple number here, so always this value would be tested again and

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again.

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But we need something else.

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We need something else that on each cycle, this number here would grow.

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OK, and the only way to do it is basically to create an additional variable called counter, it's exactly

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the hint that it gives you in the previous video and here to place the counter.

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So for starts, this value would be zero.

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All right.

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And from here, let's Sprint Party, for example, for for beginning part A. to have some indication.

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And the age is ages counter, OK, with the simple casting here.

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All right.

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So anybody could guess what will happen if I leave it like this.

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OK, let's run it and see.

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All right, so we're running this and you can see something happening here is just keeps running and

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running.

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It will keep running even after the end will after the world will end.

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It will keep running.

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Or maybe my computer could explode by the result of this because it's not going to stop for for never.

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Right.

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The reason is, let me stop it before something happens.

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All right.

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This is what you see here.

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This is the classic occasion of endless loop.

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You can see the value of five is printed endlessly, probably printed several thousand times for now.

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And what happens here?

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Basically, we have a discount or tested and the value inside the edges is always zero.

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So this value is extracted for eternity because we didn't manage to grow this number by one on each

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cycle.

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So stuck on zero here and basically print the same value again and again and again endlessly.

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OK, so this is a classic, a classic case of endless loop and you must avoid it because this is fail,

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failed programming.

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You cannot leave loops like this.

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OK, so what you want to do here is to make it like this, OK, you want to grow the counter by one

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on each cycle and if we run it now.

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Simply, you seeing that it's not endless right now.

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All right, so as you can see, the stop the stop conditioning here works and it stops as far as to

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this value right here, because this value is above 30.

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And this is the reason that these values are not printed, because once the values inside here and sell

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the Aegis counter is bigger, is bigger than 30, and once this thing became false.

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So the wire stops working.

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And also you were asked to print outside of the wire loop and the value.

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All right.

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Print me part A, the value that caused.

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Caused the loop to stop.

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OK.

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So this one was ages counter, and the reason is this printout is outside, the wire loop is right here.

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You can see an invention, right?

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We declared the wire loop right here.

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And every line, it has indention here.

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The spaces is inside the way loop.

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But once we remove the indention and we go straight from the star here.

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So this line is outside the wire loop and we just want to check what number caused the wire to fail

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to go out.

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All right.

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OK, great, so you can see exactly what value caused it to fail, because the loop went again, again,

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again and again up until it got to this number and then it exited the wire loop because this statement

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was false because this value of 32 went up in here and 32 is not smaller than 30.

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And this is what caused the wall to exit and go straight to the flow of code outside the wire loop,

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which is Rikyu.

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All right, from here in Barbie, you were asked, first of all, to go an empty line before the outboards,

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and the simple reason is just to avoid here makes of outputs, just to have some spaces.

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And if you recall from previous lectures, it's done by men like this.

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Let's just check it.

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And you can see that if I put A, B, C here and I have the empty, empty line here, once we print

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it.

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Oops, once we print it.

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OK, so you see empty, empty line right here.

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OK, if I remove it.

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You see, it's go straight ahead after this printout right here, we don't have any spaces between these

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lines.

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OK, so we want a separation here.

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All right, so in PABI, you were asked to use the same or the same way, just going to copy it from

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here.

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No need to print it again.

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But this time you were also asked to put in if and stop the loop from inside.

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Once the ages lowers, the value inside the cells is bigger than 20.

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All right.

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So age, if if the value inside the list is bigger than 20, then what we want to do first of all,

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we want to print the value.

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First of all, Part B, bring the value of, uh, that stopped.

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The loop, OK, and it goes like this age is counter.

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And how do we stop the way from inside, OK?

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You had an underlying under the warden's side, so the way to do it is exactly what we have seen in

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the advanced lecture theory is use a break, OK, just to make sure the brake worked also.

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You know what?

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Let me ask you something.

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OK, before taking the break and everything.

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Let me ask you something.

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Is this is this code correct?

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Is this flow from top to bottom here?

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Correct.

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Something is wrong here.

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OK, I will give you a hint.

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We declare counter equals zero out here.

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Then we go over a few loops here and we go up until this line right here.

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Correct.

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So once we are finished with this loop, we go straight ahead to this to this place right here.

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What do you think the first value of counter is here?

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Whether do you think the first value that will appear inside these square brackets here, let's test.

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How do we do it?

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Let's just print counter.

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OK, I'm just going to I'm just one.

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I just want to check what value of counter will go here.

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So I'm going to print it before it got to the wild.

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I have a printout right here just for me.

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OK, it's debugging just for me to know what is the value here.

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OK, let's run it and see what happens.

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As you can see, the value here is three.

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OK, so this is wrong coding, this is wrong.

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This is false because we want to start the loop fresh from the first cell off the list and we starting

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here from here, OK?

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Because what we haven't done and we should do is just going to erase it.

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We should before starting another while loop.

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We should use calendar equals zero to zeros because once it's zero, it start from the cell, from the

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index, zero from here.

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OK, and if you do not put counter equals zero here, just going to start from the counter where it's

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left and we left it at value equals three.

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OK, and this is false.

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All right.

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And also, you can see the PABI here was not printed at all because as it got here to the beginning

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of the loop, it already went out of the loop because the first value that was accepted right here is

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32.

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And obviously this this gold right here didn't run event because it straight ahead went outside of the

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loop.

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OK, now that we have counter equals zero, let's just put it under Bombi.

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All right, so now we can run it.

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OK, still, we have some problem, you can see that nothing is printed right here.

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Let's see, why do we have this problem?

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Oh, all right.

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Also, we forgot something very important.

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Again, you forgot to do this.

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Right.

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All right.

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We are growing the counter variable by one on each cycle.

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And there you go.

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All right, so what we actually do here is use the break action key, as we have seen in the advanced

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report regarding why loops and what happens here is we stop the loop from inside.

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This was our mission, OK?

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And once the value was over 20, this was the cause of our why loop to stop running and as we were asked

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as well, were needed to print the value that caused this stop.

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OK, so the value caused the Y look to run is twenty four.

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Twenty four is indeed bigger than twenty.

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And this is what made the Y look to stop running.

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And as you can see, nothing else here was printed, only the value twenty four which is this printout.

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OK.

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And right after this print out we had a break here so nothing else.

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Rund ran inside this wall.

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OK, so the wire loop exited once you got to this break.

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Action.

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OK, and also the reason here that we have to intention's.

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All right.

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We have one indention using tab and second indention is because the code that we write up in here is

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applied under the if OK.

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And this thing, for example, the counter plus equals one.

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It has one indention because this one is applied under the while and the if does not have any any action

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taken upon it.

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OK, this thing runs under the wire, only under the wire.

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It's invisible to the IV here because only two indentations is the code that is visible to the IF.

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All right, so we have completed the second part, we have stopped the while loop from inside as we

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were asked and from here we can go straight ahead to assignment number three.

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That's do as well here.

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The print slash in just we have some order like order in my eyes, order here.

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I mean, inside the output and inside here, we again need to make the counter equal zero at the beginning.

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All right.

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And the thing is that we were asked to do here is, first of all, to create a wire loop and the wire

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loop should be with a stop stop condition of sanity like this.

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And the next thing we were asked to do is to add plus to OK, to the sales values.

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All right.

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So we're going to use ages counter, which is this is the sale value.

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And again, we're going to use ages counter and do it lasta.

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OK, so we're going to take the cell value add plus to it and all of this is going to go straight ahead

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inside this cell.

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OK, so this cell will change and it will have incited these values.

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OK, so once we have completed this thing, let's print out part B or C cells.

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New values value is ages counter.

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All right.

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And again, what we need to do not forget counter loss equals block plus equals one.

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All right, and also we were asked to use an else here and see what happens once all the while loop

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exits with a number, we should go to parts, see inside or else.

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Because of the number

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ages count.

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00:16:13,320 --> 00:16:21,510
All right, so we have an exit point, meaning once this statement is false, so the while loop will

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exit itself and will go straight to the yells, OK.

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00:16:25,470 --> 00:16:34,080
So in in our assignment a here, once the while loop exits, just goes outside of the wire loop completely

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goes outside of the wire.

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Like this line is not connected to the wire loop at all in any connection.

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But here in assignment number C we have created an else statement and once the wire loop will exit,

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it will go straight to the L's condition right here.

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Let's see what happens.

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All right, we have some kind of air in line here.

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All right, so let's try to understand it is good practice can only can get an eighth string at the

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end of the string.

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OK, we also can see here.

225
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Oh, we missed the guesting, of course.

226
00:17:14,920 --> 00:17:17,480
All right, they should be they should be OK.

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00:17:20,130 --> 00:17:29,280
All right, so you can see here inside the house, so we have been successful resolving policy as well,

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what basically happened here, just enlarge it for a second.

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So basically what happened here, we went over each of these cells and we have added plus two to each

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of them.

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So five plus two is seven and six plus two is eight and so on and so on up until we got to number 70.

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And we have here a condition that once this number will be false, OK, once this statement will be

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false and in our case, 70 here.

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So this statement is false, obviously.

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And once we have 70 value right here, it will exceed the wire loop and go straight to the yells.

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And you can see the reason of getting into really is this number right here, 70, which caused the

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wire to exit.

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All right.

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I think we're done at this point.

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This was a bit challenging assignments, I must admit.

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But I think it's good to have some challenges in your life, as always.

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And also, I just want to mention and remind you again that the reason that you're doing this course

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is not for fun.

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The reason that you're doing it is to learn Python to become professionals and to become python ninjas.

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Some of you want to become front and develop.

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Some of you want to become beckoned or even automation developers.

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And you must control and dominate these fields.

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And I assure you that this is the the highest level of programming regarding these topics that you should

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know tricks that you're seeing here in the assignments and in the theory and in the example part, this

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will all will be applied once you will start working as programmers and once you will start developing

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your own software.

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These tricks and these that knowledge will help you a lot, because now I can assure you that you dominate

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also the loop's section regarding Python programming language.

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All right.

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So once we have completed this part, now it's time to go forward to the next topic.

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And I will see you in the next video.

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Thank you and bye bye.

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Good job.