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So will come again.

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This lesson is going to be a very simple lesson we are talking about two other types of control flaws

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which are while loops and do while loops very similar to four loops except that they hold different

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you know format for writing.

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So let's jump into Axford and see how they work.

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When I come in here and close this project and make it myself.

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Why project the wild project here is how we do a why do why imagine I have let get my or my thing done

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as usual.

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Imagine I have this I have an integer that in theory is called My integer ideas Krenzel is evil and

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I'm going to say why and me a complete so we can see why while condition.

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My end is still below 20.

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Let's do something that's the a statement let's say a synagogue All right.

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Now the value for the eye.

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Now this application you fire on it.

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It's what's the error that you have.

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Oh so it is called My hands my right arm on this application is going to do is going to run this indefinitely

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because it says My answer is zero.

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While my answer is below 20 keep doing this sort of while block.

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We have to actually write something that changes our our expression.

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So I'm going to say while that is true save my decrement.

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So keep subtracting from it or actually increment.

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Or in this case.

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So keep going up.

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So it goes 0 1 2 3 4 as long as it is below 20.

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It will run this let's see that.

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And once my project actually compiles builds and runs we should be able to see something in here that

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says yes it is 1 2 3 4 all the way to 20 and then it stops.

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Now if you are wondering why 20 isn't it true that it's because when it is 19 19 is a smaller than 20.

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So this will run.

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So my ins becomes 19 plus plus becomes 20.

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It prints it.

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And then this whole thing finishes.

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If you don't want to fall in that you know pitfall essentially you can do this.

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You can actually put your incrementation at the end of the while.

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So now we will see that it goes from zero to 19.

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So that is a wild while loop for us chicks for your expression and then runs your statement.

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There is another type in here that is called Dubai.

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So I'm going to say do see if it completes it for me.

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It doesn't unfortunately.

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So I'm going to say do I here's what I want to do.

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I want to say and this long this print again or my INS should have written it properly here might in

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my end is a percentage or for my of course.

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And then this is essentially going to just keep doing what I'm going to do is I'm going to say why.

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And then I'm going to give it a condition I'm going to say do Y.

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And what's the condition of they want to use.

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I want to say Do this for as long as my end is still larger than zero.

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So remember my intro was zero.

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We push it up all the way to 20.

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Now in the do I'm going to say printed and decrement it.

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Now my the.

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And the difference between a vial and a do one is in the word.

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You first check and then you do something in the do what you first do something and then check to see

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if that was the case.

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So let's run both of these

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so to better illustrate that and of course this printed the way you expected it went from zero to 19

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and then went from 20 to one let's say after this piece of art in here for a while.

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I said it's my aunt to be let's say minus five.

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See the condition is it has to be larger than zero and minus five is not.

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So let's run.

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So you see it runs at least once because the do part doesn't know about the condition it says well let's

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do this.

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What am I going to do.

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And it's like my ears what's my mind says minus five.

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Great.

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And now let's subtract from it it becomes minus 6 and continue doing as long as I am larger than zero

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and says Oh I shouldn't be continuing this anymore because already I have I have crossed the cross the

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condition essentially.

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So very simple.

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Once again Weinman does something for you as long as this condition is true adn do while does it runs

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and then checks for the condition just continues.

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If you were to write any of these with a follow essentially it would be something like this it would

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be for in my say is zero.

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A smaller than 20 plus plus and then it would write the body for a quote in here and then incrementation

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was happening within the body of the within the condition of the for loop.

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I should mention that we will see this sometime in the future that we don't often use wine or two while

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for situations where a for loop can be used Bijlee use it for situations when we are iterating or enumerating

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in an array or in a dictionary site where we really have to use a while loop because changing incrementing

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values is not within our control.

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Maybe you're going to read a dictionary and we're just going to the next item in the dictionary and

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we don't know how many items are there.

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So if we see this sometime in the future.

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For now we can almost get away for everything with with a for loop but are just preface this really

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quickly.

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So you know there is something called the Royland do wine and we'll come back to this at some point

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down the track.

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All right so let's move to.