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Hello, my name is Stephan.

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And in this lecture of our course, we will continue our project on ADTs.

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So let's get started.

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So we will add a virtual method named Makesound.

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And the virtual method is a method that has no implementation yet and only has the definition.

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Also known as the interface.

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So the derived class has to add the implementation to the virtual method using the override keyword.

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So or else the compiler will complain about it.

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So after we have a new animal class, we will make a class named dog that derives from the animal class.

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So here we will add the animal here.

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So after that we will.

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As you can see, we have.

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This animal.

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And we have the constructor get give name and get name so we don't actually need the give name here

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since we are giving name using the constructor here, but we can also use that in case if in if we need

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it.

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But we don't need it for now.

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And after that we will create a new class class here, dog.

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And this is we're going to make it the public class.

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Public, actually.

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Yes, we will make it a public class so the class dog will implement the public animal.

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Public animal.

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And after that we will write our class.

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So in this case, we're going to use the public keyword and we will forward the constructor arguments.

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So the dog here, we're going to use the string name and here we're going to use the.

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Animal name.

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Animal and name.

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We will forward this the string name to our animal name here.

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So animal name and here.

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After that, we will also need to implement the interface.

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So here we're going to make the string here, make sound, make sound and we will it.

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And the sound is going to be, of course, the woof, woof.

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Like this is what the dog sound like when they are woof, woof here.

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So here we will use a return.

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Woof, woof.

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Wolf, here.

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And as you can see, we got an error here.

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So a virtual member can be marked override here.

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So now.

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No problem here.

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Obviously.

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And this is because the string makes sound.

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All right, Here, we'll have to return Wufoo and make it like that.

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And here.

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Class dog public here.

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And this is going to return the woof woof here.

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Now we will write it like that.

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We're going to create a new class named Doc here.

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Doc is going to be let's name our doc is the.

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Here.

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Hound here.

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And see out.

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Dot get name.

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Get name is gonna be is barking.

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So.

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And after that.

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See out, See out.

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Dog not make sound.

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Of course.

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It's the Maxent.

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We'll return the woof woof here.

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So make sound is going to be, uh, the Our hound is barking and woof, woof.

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Here.

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We have a problem here.

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We have string name and animal we passed here.

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Which is gonna to overeat.

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And here we will add the virtual interface in our.

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As you can see, we have an error here and we will add the virtual interface to our animal class.

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So now after the animal constructor here, we will add the virtual virtual string.

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So we, we can also use the integer because but we will get an error because this returns string here.

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So we need to use the virtual type here.

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The string and the string is going to be makesound.

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So the interface has the implemented in derived class here.

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So zero for example.

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And here.

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We have.

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So actually now we can also run our application now and see.

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As you can see, Hound is barking.

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Woof, woof here.

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So now we have two classes, the animal class here, actually.

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Let's see here we have the animal class as the base class, and we have the dog class as a derived class.

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So as shown here, the dog class has to implement the make sound method.

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And it has been defined as a virtual method here in the animal class.

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So if we delete this.

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And as you can see, we got an error here.

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We can create the haunt here.

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So.

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And the instance of the dog class can also invoke the getName method, even though it's not implemented

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inside the dog class, since derived class derives all the class behavior to itself.

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So if you run this code again, we will see this output here.

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So let's actually compile and run inside here.

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CLS or plus plus Main.cpp output dog dot x and dog dot x here.

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And as you can see here, hound is barking.

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Woof, woof.

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Here.

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Uh, that's our.

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And again, we can say that the dog ADT has two functions and they are the these are the two functions.

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They are getName and make sound functions.

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But as you can see, we have no getName functions inside the animal class and the.

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Another necessary comment will be discussed in next lecture about ADT.

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So I'm waiting you in next lecture.