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The reference operator that the reference operator is a unit operator that accesses the object to which

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a pointer refers.

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Here, let me take the note here.

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The reference.

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Operator here.

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So this is the inverse operation of the address of operator like the address of operator.

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System programmers used the reference operator very often.

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So many operating system APIs will return pointers and if you want the access to refer to Albrecht,

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you will use the reference operator here.

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So unfortunately that the reference operator can cause a lot of notation based confusion for beginners

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because the reference operator, the Pointer Declaration and the multiple action all use asterisk.

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So remember that you append an asterisk to the.

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End of the pointer to type objects type to declare a pointer.

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So however you prepend the reference operator and asterisk to pointer.

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So like this, for example, my my variable address here.

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So.

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After excising an object by pretending that the reference operator to a pointer, you can treat a result

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like any other object of the pointer to type.

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So for example, because the my variable is an integer, you can write the value into my variable using

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the my variable address pointer here.

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So the syntax is like that, my variable address and here 995.

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And as you can see here, we've brought this variable by using a pointer, but we used the reference

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operator.

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So let's print our variable name.

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My variable.

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Well here.

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Well, let's print out a variable value and decimal and.

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Here.

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My vegetable.

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My vegetable.

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And run.

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And as you can see here, we assigned.

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This variable address using variable address with the reference operator.

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So because that the reference pointer that is my variable address appears on the left side of the equal

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sign you are writing to the address.

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Where gets here?

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My variable address is stored, so if the reference pointers appears anywhere except the left side of

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an equal sign, you are reading from the address.

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So to retrieve the integer pointer to by the my variable address here, you can tack on the reference

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operator.

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For instance, this code here will print a value stored in the my variable here.

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So here.

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The simple.

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Integer or just an integer here.

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The.

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And my variable address.

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Here and this will take from it.

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Here.

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Right.

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And as you can see here, this cutter turned the same number here.

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So.

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Q I'm.

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I want to get some code.

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Some example code that we will make it happen to show how this the reference and address of operators

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work in depth in C++.

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So let's firstly here we will create the.

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Integer my variable here and assign it to zero.

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Or let's change a name here.

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My car.

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Assign it to zero.

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Or let's change to my age here.

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It was be more appropriate for an integer.

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So integer.

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This the reference pointer here, as you can see here.

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Integer.

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My age address.

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Here.

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So I want to mention that it doesn't matter if you write the this asterisk operator here or just after

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the here, because actually it's just the your you can write the both sides but it have to between integer

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and the variable name in C++ here.

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So I will write in this time I will write here my age address address here and my age.

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I will explain all of this codes later.

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Printf.

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Here.

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Value at my age.

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Address.

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Here and we will print that a new line here.

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Will use that.

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We will use the assets, the reference operator.

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And as you know, this is the address of operator.

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We will use both of them in this example code my age address and then print F again.

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My age my age address here.

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As you know, the format specified for pointer is P and the new line.

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Here.

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We will write my age address here just and without the reference of other referencing or without the

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referencing or others of operator, because this is my address itself is just a pointer type integer

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pointer type here.

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So then we will assign, we will use the asterisk here and assign it to nine for example, 1019 nine

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here.

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Ten 129 nine.

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And then.

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And printf.

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Here.

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Value.

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Well, you add my, uh, my age address here.

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Decimal.

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As you know, this is an integer format format specified for integer.

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And we will use the asterisk, the reference operator, and my my age address.

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My age.

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As you can see, we can use the my age by itself because in direction requires pointer operant here.

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And that's why we will use you.

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We will use the integer pointer here and then print F.

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Lastly.

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Here's my bar address or my age Address.

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Sorry.

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My age address.

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Here.

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Pointer type.

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Pointer type.

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Yeah.

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Here.

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My age address without any operators.

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And let's run our code.

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And I will explain all of this in this lecture.

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So.

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First you initialize the my age to zero.

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Then you initialize to the pointer here to the pointer.

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My age address to the address of my H here.

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So next you print the.

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Integer pointed to by address here.

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As you can see, we use the asterisk operator here, the reference operator, and we will we will print

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the value of the my age address here.

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So then we write the value ten, nine, nine, 1009 and nine into the memory, pointed to my age address

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and then print the pointed to value here as you can see here and the address again.

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So then as you can see here, we this is the pointer to type and this is the address here.

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So and as you can see here, firstly my age addresses was equal to zero.

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And then.

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Uh, here.

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The.

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Address was same to and after the initialization here or changing the address to changing the variable

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of my edge variable to another var here and value here.

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And as you can see, we got the same addresses but different values.