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In this lecture you will learn about the default values in C++.

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So variables of a built in types should we initialize before you first use them?

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But there are some situations when the compiler will provide a default value.

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So if you declare a variable at the file scope.

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Or global in your project and you don't give it an initial value, the compiler will give it a default

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value, for example.

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So it's outside create an outside variable, integer outside, and then create an inside variable,

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for example, or let's increment outside by one and then print our outside.

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This is the integer manager integer.

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So we will we're going to use the decimal format specified here and then pass our outside as an argument.

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And let's compile our application and see what happens.

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As you can see here, we got to one so.

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The critical compile and run and it printed the value one.

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So the compiler has initialized the outside to zero.

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So when it's incremented to one.

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So actually let me write this here outside zero by default and here incremented increment by one, by

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plus one.

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Plus one.

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And here I'll put here one here.

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And let's create another example here which called inside.

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So create an inside, inside actual integer.

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Inside it's going to be integer.

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Type inside and do not assign anything on it.

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And let's increment inside by one plus plus here and let's print the inside variable.

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Actually, let's mention here inside ops, this is the outside, one outside.

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And then print the inside one here, print test.

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K inside.

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Yes.

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And your pass inside as an argument here, parameter here and then now.

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Let's compile and run our application.

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So as you can see, I'm sorry, I have to add the new line here.

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We don't have to add to last line, but it's okay.

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So let's add it just in case.

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As you can see inside one, outside, one.

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So.

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And here the compiler will compile and the increment operator is being used as an initialized variable.

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So in the last lecture we have another example of the compiler providing the default value static.

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So here as let's create an example here, static integer count here, for example, return here, there's

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going to be zero return plus plus count here count.

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So as you can see here, actually, it's let's instead of writing like this, let's create another count

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function so we don't mess with the main function here and call or count function whenever we want.

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And then let's add here our integer counter function.

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Then static.

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Let's add the static integer count variable here.

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And this counter, as you can see here, this function returns integer.

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So we're going to return the integer.

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As you can see, count is integer and variable is integer.

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So it's in order to more understandable since right like variable type.

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So here plus plus count.

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We will see.

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Actually, my count Plus.

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Plus my count.

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My count.

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So this is a simple function that maintains a count.

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So the variable count here, my count is marked with the static search class modifier, meaning that

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the variable has a same lifetime as the application.

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So located when so this allocated when the code starts and they are located when the program ends.

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So however, it has an internal linkage.

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So meaning the variable can only be used within the scope over it is declared.

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So the counter function so the compiler will initialize the count my count variable with a default value

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of zero, and then so that the first time counter function is called it will return the value zero.

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So so.

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But it will return the value one.

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I'm sorry I mistaken.

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It will return the value one because the increment is my count by one returns one returns one here.

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Actually.

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Let's print count.

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Function.

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From.

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Shown here and the counter here past counter.

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And let's see what happens.

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As you can see here, count function gave a counter function gave us returned as one.

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And we have a new initialize list syntax of C++ 11.

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So this is the update upgrade on the C++ language here.

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So the initialize list syntax of C++ 11 provides a way for you declare a variable and specify that you

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want it initialized by the compiler to default value for the type.

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So for example, let's create an example variable here integer A here and then like this.

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It might be strange, but I will explain all of this.

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So of course when you read this code, you have to know that the default value for an integer is zero.

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So again, it's much easier, easier and more explicit to simply initialize the variable to a value.

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E equals equals zero here.

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Of course it's more easy, but the rules for the default values are simple.

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A value of zero.

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So integers and floating point numbers have a default value of zero for a character.

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The default value is Let me show here like this.

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This is the zero.

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So for a bool is false and for a pointer is the constant null here.

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So this is the also zero.

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I want to mention here and here.

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Char default value is our default value is here.

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Parenthesis slash zero.

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Boolean bool default value is false and the floating point number is same as the integer.

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It is zero.

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And let me mention it.

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The point for pointer is pointer for here is the pound value is no Peter, which I will explain what

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null TR is.

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So in next lecture we're going to learn that declarations with without a type.

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So I'm waiting you in next lecture.