WEBVTT

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Similar to the function template.

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The class template is used to build a generic class that can accept various datatypes.

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So let's refactor our function template.

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So in this case it's the Main.cpp code by adding a new class template.

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My name is Stephan and let's get started with our lecture.

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So here now we have class animal the protected here actually let's create a new class and delete this

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old X files here.

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And right click on this C plus plus class only the class here and class template here.

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So this is actually it's not not here.

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So let's get started.

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So we're going to firstly need to include the stream, of course, include the stream.

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Dream here and we will use the namespace STD.

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So first we're going to write the create class animal.

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Class animal.

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And it's going to be the protected.

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This string here, my name.

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And after that we will make a public constructor.

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Here are protected.

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My name and here.

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It will also create the public.

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Public and the public constructor is going to get the animal as a string, as a parameter string, my

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name or name here, just name and we will pass that to my name and as the name here.

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So we will get this from here and put it here.

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After that, this will going to be empty for now.

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And we need to the interface that has to implement in derived class.

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So in this case we're going to create a virtual string here and make sound.

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Here is going to null or zero here instead of null.

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And now we will also create a string getName.

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So here in this case, this is a setter.

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And we will also create a getter.

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So we created setter inside the constructor here.

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So string get name and the this is going to be return just my name here, which in this case the my

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name is this.

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So this will return the my name here and we are done with the animal class.

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So now create the dog class here that inherits from the animal class here, class dog here and public

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animal.

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And we're going to make the public constructor public.

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Here we will forward the constructor arguments.

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Doc here.

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String name and here.

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Animal name.

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Here.

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So we will get the dog here and put it in the animal here.

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And this is going to be right this.

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And after that.

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So we forwarded the constructor arguments.

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Now we need to copy assignment operator overloading.

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So in order to do that after the public.

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Uh, the.

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We're gonna create the void operator.

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Void operator.

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And it's going to be a constant dog here and operator Dog here and.

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Operator And the or instead dog here.

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Let's make it the.

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Uh, so we created the void operator here.

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And yeah, we also need to assign it to something here.

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So we need to name my name.

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It's equals d.my name here, as you can see here.

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And after that we need to implement the interface.

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So in this case it's going to be the Makesound and we will override this Makesound here and we will

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implement the interface.

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So this is the interface actually not here.

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String, make sound, make sound here and we will override.

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And here return here.

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In this case, the return is woof, woof.

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Here.

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Narrator.

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NARRATOR Heading level one.

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Exiting.

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Narrator.

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Here.

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Uh, now we're going to.

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Here.

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We have done with it.

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Void operator is yes here now we have done with the dog class.

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Now we need to also create the cat class.

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So in this case, we're going to create a class cat here and it's going to be public.

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We will get the animal here.

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So the public is going to be we will also forward the constructor arguments, as we did earlier with

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the dog example here.

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So now we're going to Cat.

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String name and animal.

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Animal name here.

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After that, we need to also do the operator here, copy assignment here.

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So in this case, it's going to be.

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Void Operator.

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Void operator.

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Operator equals.

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Equals the const.

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Constant.

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The cat and the.

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Here.

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We will also need to add braces and we will assign my name to the my name here that we have inside the.my

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name.

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And now we need to implement the interface here that we created the Makesound interface.

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So.

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Here.

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The string here string makes sound.

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Here and over it.

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Return.

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What the cat makes the mew mew hear.

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Yeah.

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Mew Mew here.

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And we will also create a template here.

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The temp actually spiked here.

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So we need to create a template after this.

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So it's going to be like, uh, the class We created three class here.

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Make sound here.

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Here, make this look nice.

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And after that, we will create a template, as I said.

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Pamphlet is going to be the type name.

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He.

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Here.

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And we will also create a new void.

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We will, as we did in previous lecture, we will create a new void named getName and make.

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Here.

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Actually, we don't need the.

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Here.

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So the get name and make sound here, it's going to be the T or T and operator here and we're going

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to make it the animal.

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Animal or just an.

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Our animal.

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Yeah.

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The animal is okay.

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The animal.

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And here.

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The animal.

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We will see out the animal Dot get name.

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And goes here.

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See out the animal that makes sound.

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Makes sound.

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Is the get name and make.

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So we will also need the get name and make sound here and line.

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And after that we will also create a new template here that of course the type name is going to be also

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T here template.

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Template.

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The type name.

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Type name is going to be here.

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After that.

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And we will also create an animal template class animal template.

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Here we will first assign private that T animal or T my animal.

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And after that we will also create something public that we will make the constructor here, the private

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public here.

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T my animal.

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The public is going to be.

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Uh, the animal template public is going to be animal.

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Animal testing.

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This will get t dot animal.

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And here we will pass this to my animal.

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Here, my animal.

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And we will.

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Yeah.

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Here.

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We will pass the animal here to this oops, this animal to here, as we did in the earlier animal here.

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And after that.

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Here.

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We will open and close the curly braces.

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After that, we will create a getName and make sound here.

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So void.

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Get name and make sound here.

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The crowd is going to be not the animal in this case.

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It's going to be my animal, my animal dot get name.

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Yeah, they get name.

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Yes yeah my animal dot get name and.

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Glacier.

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Our animal name.

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It goes like, see out my animal, but make sound.

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Here and in line.

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So first we will print the our animal name.

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So animal in this case, the dog here, dog goes here.

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Woof, woof here.

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And then we will end the line.

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And this is the new we will click new line for us.

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And now let's start creating our main function.

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But first, let's check the lecture time.

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Yes.

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So let's create our main function now.

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After the closing the animal template.

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Now we will clear the integer main integer main function.

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And this going to be the dog here.

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Dog.

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It's dog.

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In this case, let's actually make this Labrador here and animal template template.

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Uh, dog is going to be.

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Bulk is going to be a doc template.

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Doc Template.

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Doc.

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Now the dog template will.

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Look template dot get.

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Get.

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And get name and make sound here so get.

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Don't talk to me.

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Get name and make sound after will also apply the same for the.

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Kat Von here.

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So, Kat.

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Kat here.

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New Kat Instance.

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Kat.

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Kat.

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Kat.

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Here in this.

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Estonian.

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Estonian.

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Kat.

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Here and this is going to be an animal template.

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The cat.

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Is going to be make this cat template.

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Template here and cat will pass the cat here.

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Now the cat template dot get name and make sense.

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We will use this function.

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So as you can see in this code, we have a new class named the Animal template.

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Here.

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So it's a template class and it can be used by any data types.

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However, we have to define the data type and in the angle braces here.

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So as we can see in this code, when we use the instances, the doc template and the cat template here,

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the doc template and cat template here, um, they use this instances.

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And we will use the angle braces here.

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So if you build and run the code, we will get the output as we did in previous lectures.

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But in this case we use the classes to make this real.

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So now we're going to open this.

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Actually, let me open the CMD here.

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Here.

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Let's actually look what we have here.

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And this is our CPP file.

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And this is our main.cpp file.

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So here this class template dot cpp file is this the newly created and the main is this main.cpp here.

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So now we just going to compile the class template dot cpp g++ class template dot cpp here.

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And as you can see here, it compiled without an error.

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And there here and as you can see here, we just create a new file here.

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So let's actually run this.

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And as you can see here, the Labrador goes woof, woof and Estonian cause cat goes moo moo here.

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So that was our example with the class template.

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So I'm waiting you in next lecture.