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So far In this course, initialize lists have been treated as a kind of C++ 11 construct and a bit like

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the built in operation.

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So in fact, when you use the initialized list syntax using the braces here, the compiler actually

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creates an instance of the templated initialize list class here.

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So if an initialized list is used to initialize another type, for example, in this case the vector

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here.

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Then the compiler creates an initialize list object and with the given values between the braces here

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so and the container object is initializing the initialized list iterator.

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So this ability to create an initialize list object from a braced initialize list can be used to give

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a function a variable number of parameters.

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So weight all of the parameters must be the same type in this case here.

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So in order to use this initialize or list, we have to firstly include the initialized.

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Initialize the list.

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Hit the file here, and then we're going to create a new function named E some and.

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We can return the integer here some and inch.

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List here and.

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Then.

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This initialize the list will take the integer values here and make it values.

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So this sum here takes the parameter values.

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This will take one parameter and the type of initialize or list integer here.

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So which here?

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Integer sum equals zero here, for example.

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And we're going to create a false integer values.

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We're going to iterate throughout this parameter.

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Values and the test for love.

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We're going to use this as the going to some increment, some by one at every or some by e here, at

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every iterating here.

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And we're going to after this, we're going to return the.

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Some integer here.

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So in the main function, we're going to create.

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We're going to make a actually, the main function is going to just print something and call this sum

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function here that we created here.

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So see out.

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Some.

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Here and.

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And blind virtually.

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We're going to call just an empty some and see out some here.

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We're going to pass the values here.

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In this case, we're going to pass the negative values starting from six minus six, negative six here,

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five or three to.

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One here and one.

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So.

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See out see out some in this case, we're going to make give it a ten, 20, 30 and end line here.

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So in this case, we're going to get the if a the non object to this some function, we're going to

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get zero.

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In this case, we're going to get the -2021.

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And in this case, we kind of get the 16, as you can see here.

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And the sum function here has a single parameter.

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Initialize a list integer here, which can only be initialized with the list of integers here.

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So the initialize list class has a very few functions because it only exists to give X to the values

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in the brace list here.

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So most significantly, it implements a size functions that returns the number of items in the list

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here.

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So you can use values that size.

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As you can see, this will return the number of items in the list.

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But let me mention it.

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So when you know this code you're going to see.

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Returns, number of items in the list.

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So here.

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Size function returns the number of items in the list.

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So.

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And the begin and end functions in return pointer to the first item in the list and to the position

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after the last item.

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So these two functions are needed to give iterator access to the list, and it enables you to use the

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object width with the range for loop here.

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So as you can see here, we when we compile the code, we're going to get zero -25, 21 and 60 here.

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So in this example, the main function here calls this function three times the sum function three times

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each time with the breast.

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Initialize the list here as you can see here.

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So on the function we return a sum of some of the items in the list here.

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And as you can see it, will this sum here multiply or this will some of the numbers in the list?

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So clearly this technique means that the each item in the variable parameter list has to be the same

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type or type that can in can be converted to a specify, specify type.

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So you will have the same result if the parameter had been vector.

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And the difference is that the initialize, initialize or list parameter requires the list initialization

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here.

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So if you make it like this two point make, give it 2.5.

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And as you can see here, we are going to get error because the initialize list can only you can just

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only pass the values that has the same type as this parameter here.