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Initial users.

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Initially users were touched upon in the last lectures, but we will go into more depth here.

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So for built in types, you must initialize a variable before you use it.

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So for custom types it is possible for the type to define a default value, but there are some users

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in doing this which will be covered in next lecture.

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Which in next chapters.

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Which in which.

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Yeah, in classes chapter of this Oxley Udemy course.

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So in all versions of C++, there are three ways to initialize a world in type.

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The first here three ways to initialize.

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Boiled.

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Point in time.

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The first is assignment, which I will explain all of this assignment function.

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Syntax.

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Thanks for calling.

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And constructor.

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So.

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Here.

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Now let's try.

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Firstly, try with assignment, then function, then syntax and then call a.

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Actually it's a four way, so I'm sorry for it.

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It's four ways for colleague in slicers.

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So still C plus 11.

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Another way to initialize variables was introduced construction toward list visualizer.

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So there are four types here, as I said.

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So let's firstly create our in our codes and writer codes and use for initializes here include standard

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steel here just for.

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Putting it here So integer.

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Actually, we didn't need here.

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I just wanted integer.

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E here.

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Integer g equals integer two which I.

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Yeah.

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Yeah.

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It's it's.

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It seems like pretty strange, but I will explain all of this.

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Don't worry.

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Integer key here.

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Actually.

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Let's make this e, b c integer C tree or like this tree and then integer M four.

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Integer RD four.

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So as you can see here, we did we initialized for four variables to four integers.

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So the first of these three is the clearest types.

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So it shows using an easy to understand syntax that the variable is being initialized to a value.

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So the second example here initialize a variable by calling the type as if it is a function.

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So as you can see, the second is a function calling it by function.

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And the third example calls the constructor of the integer type.

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So this is a typical way to initialize custom types, so it's best to reserve the syntax just for custom

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types.

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So and the fourth here, as you can see here, syntax is new here.

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Excel.

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Let me write it here.

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New, new to C++.

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So this is the kind of new to C++.

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It actually came with C++ 11 and initialized initializes the variable using an initialized list between

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the curly braces here, as you can see here.

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And just to confuse things slightly, you can also initialize a built in type using the same syntax

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as an assignment to a single to a single item list.

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For example, integer E here equals equal to here and five like this.

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So you can assign this operator like this too.

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So now I want to print these variables just in case to show that these variables works and you can print

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this value to screen.

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So let's print print f.

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Okay here.

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Stop.

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Decimal.

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New line.

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Decimal.

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New line.

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Decimal and new line.

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Decimal.

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New line.

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Lastly, actually, let's add five decimal here.

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Excellent.

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Same with the set here.

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And new variable.

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One, two, three, four.

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The financial and then the these variables.

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He equals.

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The calls.

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Sea Eagles.

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Cruelty.

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The cruelty.

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And E quality.

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Yeah.

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And then.

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E.

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B.

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C.

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D.

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E.

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And actually I've got the right mean function and germane here.

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And then.

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So actually is the line, the writing these things is pretty easy.

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So as you can see here, it added one tab between the this last line automatically.

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So now let's print our function actually.

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Take this vegetables to.

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Main main function here.

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UPS by the telco.

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Take this to main function and compile and run our application.

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So as you can see here, we initialize with the first type, assign assignment type and print it to.

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Bring it to console.

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Here we come online and then we did the function B two, C three, D four.

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And these are the same actually with syntax calling, calling a constructor type, which is a kind of

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new to C++ language.

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And I'm going to show you another thing.

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So just initializing the arrays here.

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So actually.

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Initializing arrays.

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Initializing.

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Actually, it's print F.

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Initializing types of initializing types.

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And then.

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Have just print print test.

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Initialize.

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Race and let's create our race.

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So this is a really confusing things.

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So the type here, the type E here is an integer, but not an array.

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So as you know, we can write arrays like this, for example, integer integer, birth year, for example,

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birth years, and then, for example.

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One.

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For example, like this we can with this quarter versus we always did just creating a rate things,

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as you can see.

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But here we're signing something just one variable to.

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Integers.

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So this is kind of confusing.

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I know.

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So just to configure things slightly, you can also initialize a builtin type using the same syntax

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here as an assignment to a single item list.

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So recall that in the last lecture we created an array with the birthdates and I did this.

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I brought this code again.

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So this creates an array of four integers.

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So the type of each item is an integer, as you can see here.

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But the type of the array variable is integer pointer here into the asterisk.

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So the variable points to memory that holds for integers.

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So similarly you can initialize also initialize a variable to be an array of one of them.

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For example, integer John.

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And.

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For example, John, for example, this rather John's birthday, 1988.

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And as you can see here, we did.

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Creating just a single array so we can use it as the just usual integer here.

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So this is exactly the same initialize initialization code that C++, C++ 11, C++ 11 allows to initialize

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a single integer.

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In addition, the same syntax is used to initialize instances of record types as you know, structs.

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Yeah.

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So adding another level of potential confusion about what syntax means.

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So it's best to avoid using the curly braces for variable initialization and use it exclusively for

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initialization lists.

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So just avoid this.

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I just, I just want to show you that C++ 11 has this feature.

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So however, there are advantages of this syntax for casting as explained shortly.

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So the core libraries syntax can use provide the initial values for any of the collection classes in

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C++ Standard Library.