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So our next up against polymorphism will chat functions and abstract classes, so this is most like

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kind of a special topic we are covering today.

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So let us deep dive into polymorphism answer.

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So among one polymorphism concept you have already discussed in our previous section, which was basically

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on all our learning, like we had different operators, right?

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And we now are using these operators for a different purpose.

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So like we had, let's celebrate that.

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But we changed the meaning of the plus operator in our previous classes.

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So that's an example of what a polymorphism which means polymorphism means.

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Multiple forms like the same thing is achieved differently.

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So we had a list operator and we were using that cluster operator for both adding numbers and also concatenating

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some strings.

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So that's an example for that polymorphism, which means like the same operator was used in different

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forms.

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Similarly, we do have one more concept in C++, which is called runtime polymorphism.

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So for achieving runtime polymorphism, we usually use our feature in C++ GUI virtual function.

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So let's discuss what is meant by individual function.

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First ever virtual function, a simple function we just declared within a base class and redefined by

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a class.

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Suppose we have two classes Class A and Class B, so Class A is the bad and class, and Class B is actually

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that derived class or inheriting the properties of that class and supports classes having a property

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on a function card.

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So that's a function.

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And in class AA, it's having a meaning like we want to change the meaning while we are impacting the

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same function to Class B.

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OK.

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So for that purpose, we use a concept like virtual function.

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What we will do is like we will actually define our show function as it will actually function inside

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the bat and class.

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It will be like virtual show.

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And this will gosse that we can change the definition of this show function being headed that same show

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of function in under Class B.

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So that's that symbol for it with a gel function.

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And in order to make a function virtual, we use a key word like what?

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OK?

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And when actually the function definition is taken into consideration.

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It's only during the runtime, usually in C++.

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Most of the things most of the meanings of the function, most of that are like definitions, resolution

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of variables.

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Everything will take place at compile time.

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But if we are using a virtual function, the meaning of that virtual function is derived or let that

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runtime.

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So that's the difference between a normal function and it will actually function.

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So I have already discussed this topic, so we have polymorphism, which means processing the same thing

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in different ways.

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OK.

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And the polymorphism can be divided into two.

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One is compile time polymorphism, and it's having two separate divisions, as I discussed already function,

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overloading and operating our learning, which we have already covered in our previous section.

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Now we have one more type of polymorphism, which is called runtime polymorphism, which will actually

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depend on the work functions concept.

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So let's dive into the demo right now so that you will be able to understand how the gel functions work.

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So I will explain this program to you.

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So it's having two classes one classes, card bays, glass and another classes derived class, and you

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can see a single inheritance happening out here like glass derived is actually inheriting the properties

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of base class.

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And we do have dual functions inside our base class one, this virtual white brain function and virtual

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function.

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And what happens when you execute brain function in base class?

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It will print brain based class that will be the output.

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And what happens when you bring the show function from the base class?

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It will just print show based class.

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OK.

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And now we are deriving that and we are redefining that.

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But if you look at here this white print, it's actually printing this derived class and show is also

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redefined out yet and it will be printing the entire class.

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OK.

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It will be showing that at.

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That will be the output of this function.

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What is happening is like we are actually creating a wind up for our very own glass.

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OK.

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We are creating our point effort for their glass out here and we are actually printing the function,

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OK, using the brain function of that child object.

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OK.

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So it will be like that object is what drives glass and it will be printing the value for the glass

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so that the rind glass object is D. So it's equal to the entire brain, and this is equal to the brain

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because this is a pointer of an object that we have already discussed.

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So you will be at mass any.

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You can access this drive glass and access that brain by using this index so it will be actually binding

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to this glass and it will be executing this print.

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And now we do have one more thing like show function, which is also like printing on that order here,

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right?

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It will be like printing show derived glass, but it's also inside the building of the glass.

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But what happens when you execute this function?

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So that's something we need to know, right?

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So let me switch to desktop now you have to compile this fire.

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So we have the syntax C++, the ritual FNC, dark CBB.

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Now it's come by.

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Now let's bring it by or out to get out of dodge.

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Slash it out.

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See if you know what is on here.

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The drive glass is actually printing that using the print function out here, but many also here.

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The show function is not showing that the right glass.

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This should be the output of the show function, but it's just printing that show based glass.

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That means it's actually printing the show function or here.