WEBVTT

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We haven't talked much about memory this far but I want to talk about it here because it will be the

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theme of the next three sections.

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We talked earlier that variables have a location in memory which is accessed by their name or identifier.

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Well we can think of memory being like a big long list of memory cells.

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Each one byte and size and each one with its own unique address.

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Each cell can be located in memory using this unique address.

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So the address 1001 would be right after the address 1000.

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So in my mind I have a picture of what a cell really looks like.

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In fact this is kind of how I think of variables in general.

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So we have this kind of first slot which is the address portion says a beer one thousand one or 1000

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or whatever the address may be.

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And then here you have the value of what it is say we made some kind of X equals to 5 like this.

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Well this index has an address of some kind.

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We don't know exactly what that is but the value would be five year right.

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OK.

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So of course different types have different sizes so an integer would be for these cells but really

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I just think of it as one big cell with an address and one value.

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So remember that there are no guarantees where your variables are stored but we can actually get the

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address of a variable.

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So let me just show you how to do that.

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So we have our variable x.

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And if we just say seek out the address

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X is in.

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We do this we say ampersand and X and if we run this you'll see what the address is.

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So it's this big long bizarre kind of looking thing.

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Those those if you've seen this before.

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No this is hexadecimal.

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K so this single edge ampersand is known as the address of operator and we can do this with any variable

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to get its address.

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So here this is actually just an integer

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but know that the address is not considered an integer type so we don't really know what the type is

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yet but we'll see this in the next lecture.