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‫Welcome back.

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‫In this video, we are going to check out autos and locals and also breakpoints a little more.

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‫So we saw how to use breakpoints in the last video and we created this one breakpoint at the point where

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‫we create this local list or this local variable called friends, which is only available in our main

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‫method.

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‫And then we can, of course, go ahead and create some more of those breakpoints.

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‫So I'm just going to create two breakpoints.

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‫Now, let's say we want to have a look at our breakpoints.

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‫And in this example, it's super easy because we only have those two breakpoints, right?

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‫So they are visible all the time.

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‫But now imagine we did this.

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‫So we have summed it up.

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‫We really just want to break it down on the higher level.

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‫And now we only see this one breakpoint.

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‫But where are all the other breakpoints?

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‫Well, what you can do is you can start.

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‫And then or start debugging by pressing a five.

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‫And then the other thing that you can do is you can check out your breakpoints.

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‫So control alt b is the shortcut or you can just go to Windows breakpoints here from debug debug Windows

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‫breakpoints.

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‫And that will open up this little tab here, which shows you the different breakpoints that you have.

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‫So we have a breakpoint in program, CSS line ten, character 13 and another one in program CSS line

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‫21 for character 13.

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‫All right.

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‫So these are the two breakpoints that we have.

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‫And now in order to get rid of a breakpoint, what we can do is, of course, we can press on the breakpoint.

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‫So here on the left hand side, we can click on it.

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‫And as you can see, it completely disappears from our breakpoints.

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‫Once we do that, we can also just deactivated breakpoint.

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‫Now you can see it's white in the middle.

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‫So let me do that with this breakpoint here.

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‫You can see it better.

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‫You can see now it's not fully red anymore.

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‫It's not filled with red anymore.

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‫It's filled with white.

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‫All right.

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‫So it's still there, but it's deactivated.

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‫So you can deactivate breakpoints any time with this window.

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‫With this breakpoint window.

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‫All right.

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‫So this might not be useful in our specific case here because it's a super short program.

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‫Right.

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‫We don't have too much going on here.

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‫But once you have a program where you have breakpoints in many different files, this comes in handy

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‫and it really helps you out there.

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‫All right.

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‫So the next thing that I would like to show you, and that's a very important one, especially to figure

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‫out where your bugs lie and that's to use locals and orders.

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‫All right.

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‫Let's start with orders.

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‫You can see we have this new window here called orders.

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‫Orders will automatically show us the variables which are around the current breakpoint so the ones

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‫that are relevant currently.

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‫So there's this args variable, which is this one here at the top from our main method.

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‫So this args variable and then we have this friend's variable which currently is null.

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‫And once we go to the next step, so we step over.

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‫We can see that now.

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‫We have friends and party friends.

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‫So all those shows us automatically the variables that are surrounding the breakpoint that are close

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‫to where we are currently.

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‫All right.

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‫So here I'm with friends and you can see that we have seven entries there.

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‫And then we have party friends, which is at this point null.

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‫But once we step over, we can see now party friends is what is looked at.

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‫All right.

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‫So we have this variable count and we have this variable party friends, which has some additional information.

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‫You can see the count of party friends is zero at this point.

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‫You can see the type here if you want to know more about it, it's a system collection list.

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‫And then we have this party friends count, which is also zero.

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‫All right.

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‫So Count, which is this one here and this one over here.

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‫And then we have party friends, which has a count of zero.

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‫All right.

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‫So that's the general idea or actually party friends.

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‫And then we have count.

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‫So it's two different things.

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‫As you can see, there is the party friends count, which is the amount of party friends and there is

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‫the party friends list, which is the list which currently doesn't have any friends in there or any

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‫entries in there.

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‫All right.

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‫So that's our autos.

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‫And it's super handy when you are looking at variables that you currently have right now.

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‫Now, what you also can do is you can modify those.

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‫All right.

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‫So you could modify the value here.

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‫You could go ahead and enter five and test how your program behaves once you change the value to a different

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‫value.

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‫As you can see, I've changed it to five and now I could see, okay, how would my program behave once

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‫I add a or enter a value of five, for example?

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‫All right.

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‫So that's one thing.

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‫The other one that I would like to show you are locals.

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‫But before we do that, I would like to show you the watch first.

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‫So let's go to the watch and watch opens up this.

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‫One note, which looks similar to what we have just seen.

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‫And now you can add items to watch, by the way, at the bottom.

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‫Autos is still there, so it's just a new tab here at the very bottom.

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‫And here is watch one.

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‫That's because, well, breakpoints has taken some space and it's important.

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‫But what we can do is we can at any point we can drag out all those and have it at the side here so

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‫we could compare them.

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‫So let's say I want to add my friends, so I'm just going to add party friends to my list.

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‫All right.

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‫Party friends entered and you can see the party friends count is zero.

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‫Then it's always important to where you are right now.

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‫So at this point, I'm over here, so I'm just going to look at Current Friend and let me enter.

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‫As you can see, I'm getting an error name.

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‫Current Friend does not exist in the current context, so it doesn't exist at that point yet, but it

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‫will exist later on.

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‫So let's also look at friends because friends is also something that doesn't exist in the current context.

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‫Why is that?

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‫Well, because right now, as you can see, the arrow is within my get party friends.

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‫So we're within this method.

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‫Now, the scope of our whole variables is within this method and this friend's variable and this party

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‫friend's variable.

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‫They are not available in here.

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‫So this is not the party friends that we're looking at here.

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‫All right.

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‫Because the party friends that we're looking at is this one here.

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‫Why is that?

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‫Well, it's because of scope.

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‫All right.

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‫Scope is a very important concept, because a variable that is created within a method is only available

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‫within that method.

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‫That's why we can't use friends or party friends from our main method within our get party friends,

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‫because it's a different method, right?

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‫If we created them globally.

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‫So if we created them here at the top as fields for our class, then they would be available in all

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‫of the methods.

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‫All right.

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‫So that's really important here.

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‫I looked at into scope in another video, I think.

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‫But here it's really, again, very easy to see because, well, we can directly see the values that

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‫we get.

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‫All right.

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‫Now, let's go ahead with the program and let's just.

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‫Continue.

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‫Let's just say, okay, let's continue.

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‫You can see now party friends and current friends are available because now current friend is null.

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‫So we can just go to the next step and we can see that the current friend is Michele.

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‫So our program gives us those values and at the same time at the right hand side, all those constantly

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‫gives us the closest values, values that are closest to the breakpoint that we are at right now.

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‫All right.

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‫So once I jump out and I jump out again.

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‫And then I see I'm at friends, so I had to jump up multiple times.

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‫But now I'm in the main method again because I jumped out of my get party friends and now party Frances.

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‫Now my current friend is Carlos and my friends is the count of two, so I only have two friends in my

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‫list.

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‫Now that's a weird one because I thought I had seven friends in my list.

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‫Well, that's something that we have to look into in a little more depth, because what we're doing

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‫is a huge mistake and it's a very beginner kind of mistake we are removing from a list now we're passing

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‫by reference, we're not passing by value, and that's something that we will look into in the next

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‫video just as a little preparation for you.

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‫So and then before we do so, I would like to check out another window.

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‫And as you can see, there are plenty of windows.

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‫So you can learn so much about debugging.

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‫If you just check out the different windows and see where your program is at every single line and what

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‫the state is.

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‫And you can also check out the memory and so forth.

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‫But what's important for now is the locals.

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‫So I would like to show you locals.

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‫Locals shows you the variables that are available in the local context so in the scope that we're currently

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‫looking at.

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‫So as I just said, the scope is the method that we're in.

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‫So let's start it again.

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‫Let's start debugging.

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‫And by the way, you could once it's debugging, you can also restart debugging by pressing this button

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‫over here, the restart button or by pressing control shift.

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‫F five So in the current context, that's the local window where it's important.

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‫We're currently at locals, not at Otto's.

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‫We're currently looking at locals.

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‫So we have arcs, which is this main arcs, the string out here, this string list or array.

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‫And then we have our friends and we have our party friends.

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‫So these are the variables that are available within this main method, and that's why we are currently

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‫being displayed, those two values.

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‫So we can step over, we can see, okay, we have seven friends, we can look at our party friends,

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‫we can see a count is zero, but the count variable itself is four and we have list.

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‫So now we're not looking at friends anymore, but we're looking at the list.

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‫So what is list?

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‫Well, list is this variable that was passed to us.

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‫So you can see here this list was passed to us and this list has a count of seven.

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‫All right.

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‫And what's in there?

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‫Well, there are all of the different names that we have.

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‫All right.

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‫So that was locals, autos and breakpoints.

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‫And in the next video, we are going to fix our back because we still have our bug in here because we're

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‫checking for the wrong value.

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‫But at the same time, we're going to see how to fix some other problems that we have in our program.

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‫All right.

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‫So see you in the next video.