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‫Welcome back.

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‫I hope you try to finish this challenge where you had to create several classes and subclasses or several

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‫deriving classes.

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‫And yeah, let's just go ahead and start with it.

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‫So let's create a new class called Employee.

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‫And this employee should have several information.

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‫First of all the names so I'm just gonna go ahead and prop and it's going to be a string property with

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‫name.

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‫Then we have another one, prop string, first name.

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‫And the third one is a property called celery.

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‫So now we have those three properties and we can go ahead and create a.

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‫Constructor, public employee, and that one takes in a name, a first name and a salary.

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‫And of course, we need to set those.

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‫So this dot name is going to be named this.

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‫The first name is going to be first name.

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‫And this dot salary is going to be salary.

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‫All right, so that's our constructor.

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‫And then.

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‫Our employee should have methods called work and POS.

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‫So let's create those public void work.

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‫And this should just write somewhere like I am working.

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‫And then one that is a void called pause, which is just going to write something like I am having a

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‫break.

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‫All right, so that's pretty much our employee.

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‫And now we want to inherit from that employee and we want to go ahead and create a new class called

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‫Boss.

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‫So this is going to be both actually.

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‫Let's change that.

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‫Let's just delete this class and create a new one.

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‫We could have renamed it, but creating a new one is more convenient actually boss like that.

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‫And now that boss should have an own property.

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‫As stated here.

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‫So let's go back.

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‫Created your own class boss with a property called Company Car and the method lead.

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‫So let's create those property and this one should be a string and I'm going to call it company car.

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‫And then we have the method public void lead.

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‫And this one's just going to say something like I'm the boss or something like that.

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‫CW Boss.

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‫So great English grammar in here.

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‫I'm boss.

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‫And now we should go ahead and create another driving class of employees called trainees or trainee

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‫with the properties working hours and school hours and the method learn.

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‫So let's just do that.

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‫Let's create a new class called.

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‫Trainee.

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‫And that trainee, by the way, the boss didn't derive from employee, so should just add that employee.

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‫The same goes for our trainee.

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‫It also derives from employee.

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‫And now, as you see, as it does not have a.

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‫As we don't have an empty.

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‫Constructor in here.

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‫It's complaining.

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‫So I'm going to create an empty and structure, which is just going to say the name is going to default

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‫as Dennis, then the first name is going to be defaulted as actually the first name is Dennis.

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‫The last name should be pun Utah in my case.

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‫And then we have the salary, which is just going to be let's keep it simple, 50 grand, not very accurate,

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‫and we don't even talk about the currency.

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‫All right.

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‫So now if we say that, you see the error disappears because if I don't have that.

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‫So just a second, let's get rid of it.

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‫It will or it will be unhappy here.

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‫So you say there is no argument given that corresponds to the required formal parameter name of employee

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‫employee string string int.

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‫So either that or we have to implement a constructor in the boss class.

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‫Which I think we should still do.

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‫So let's do that, because if we create a boss, we want to inform or we want to add the information

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‫about this company car.

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‫So let's create a public boss, which will take a string called company car.

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‫Company car, then a string called name, string called first name and an integer called celery

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‫root.

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‫And now when here we just say something like this dot company car is equal to comp per ne car.

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‫Now all of the other ones are missing.

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‫And we can, of course, go ahead and say something like this dot name is equal to name, but we can

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‫even make it simpler by using something called the base.

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‫So we're using base name, first name and salary.

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‫So what that does is it simply uses the approach that we had here.

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‫So this one here, so it's using this constructor for us.

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‫So we don't have to write all of that initialization in here.

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‫All right, before we do anything else, let's test that.

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‫So let's create an employee.

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‫Or actually, let's create a boss.

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‫So let's go ahead with an employee.

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‫So employee is going to be Michael

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‫my co and he is a new employee and now we could go ahead like that.

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‫So that will be Dennis.

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‫So it will just take this constructor here, but as I prefer to inform about the real Michael, so it's

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‫going to be Michael Miller and his salary is going to be 40,000.

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‫And now we can, of course, go ahead and call methods of Michael.

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‫Michael.

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‫And we had well, he should work, so please go ahead and work.

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‫And Michael, go ahead and make a pass.

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‫And then finally console Todd Reed key in order to keep the console open.

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‫So let's test that.

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‫And we are.

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‫So first he's working and then he's having a break and that's great.

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‫Good guy, Michael.

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‫Now we can go ahead and create a boss.

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‫So let's go ahead and say boss and I'm going to call him.

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‫Chuck Norris is going to be a new boss called.

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‫Well, he needs a company car.

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‫What's it's going to be for Ferrari, then a name.

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‫And this will be Norris.

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‫Then the first name will be Chuck and the salary is going to be over 9000.

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‫So just a very high value and it's actually not accepting that value.

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‫So that was too much for an integer to bear.

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‫So that's a lot of money that Chuck is making and now we can go ahead and make him lead.

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‫So let's Chuck Norris be our leader and he's going to lead.

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‫So let's see what he says.

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‫And he says, I'm boss.

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‫And of course, we can go ahead and add some more information about what he's saying.

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‫My name is.

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‫And then we just use something like his name and you could even add some more information about his

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‫salary, all of those kind of things.

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‫So that was not part of the exercise, but I'm just adding it here.

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‫So we have a little more information about this guy, and I'm going to start with the first name and

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‫then I'm going to go ahead with the last name or actually the name.

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‫And as you can see, I can use them even though I haven't created those properties in my boss because

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‫I'm inheriting them from employee.

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‫And now if we run it again on boss, my name is Chuck Norris and that's awesome.

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‫So Chuck Norris is our boss.

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‫Now, our trainee needs also to do something, so he should have his own properties, which is for one,

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‫his working hours, working hours, and another one which is going to be his study hours or school hours.

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‫So it should be the study hours in the sense of him studying at home.

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‫But actually, I'm not sure whether you are aware about the training system in Germany.

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‫You have a three year training system in which you learn a job and it's similar to well, it's not really

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‫similar to the college, but that's pretty much like after ten years of school, you go there, you

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‫go to this, you study a trainee job, and you do that for three years.

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‫And afterwards, you're an expert, not an expert, but you are well educated to do the job quite well.

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‫So you have like 60% of working time or even 80% of working time and then one day of school.

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‫So you go to school in order to learn more detailed, important information about the task at hand.

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‫And that's something that works quite well for Germany.

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‫So we don't need to everybody to go to university in order to get a good job or everybody to go to college

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‫to get a good job.

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‫So this is quite an alternative there.

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‫All right.

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‫So just a little side note and now let's go ahead and create a trainee constructor and it will need

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‫the working hours, then the school hours,

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‫a name, a first name, string, first name, color like that, I think like this and int salary.

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‫And now here we're using base as well.

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‫And if you didn't do that, that's totally fine.

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‫No worries.

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‫It's just for you to know that you can do that.

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‫So name, first name and salary.

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‫I'm just going to take the ones from our base class and now I just need to assign the working hours.

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‫And actually here I want to have this start working hours, which will be our working hours and then

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‫this dot school hours, which will be our school hours and that's it, right?

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‫Name, first name and salary are from the base class anyways.

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‫And now we need to methods learn.

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‫And what was it.

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‫Learn and work and now work.

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‫The trainee should work slightly differently than the.

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‫Boss or the employee.

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‫So we learn.

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‫And here we just write something like.

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‫CW I'm learning for so many hours like this and it will be the learning hours or school hours.

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‫Like that.

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‫And now the last method will be public void work.

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‫And now this one should actually override our employee method console, dot, right line.

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‫I work for 0 hours.

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‫And by zero.

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‫I don't mean zero.

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‫I mean the working hours.

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‫So now if you see that it says hides inherited member employee work used use new key word if hiding

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‫was intended and that's something that we will cover in detail in the next chapter where we're talking

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‫about polymorphism.

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‫But now let's just create a new employee and this time it's going to be a trainee employee.

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‫So I'm going to call her Michelle and she's going to be the new trainee.

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‫Michelle, actually, she needs working hours.

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‫Let's say she's working for 32 hours a week.

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‫Then she goes to school for 8 hours a week.

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‫Her name is Michelle Gardener.

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‫So.

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‫Michelle and her salary is something like 10,000 a year.

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‫All right.

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‫So now let's go ahead and ask Michelle about her studying.

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‫So how is that going?

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‫And then Michelle, the work.

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‫Now let's run it and you will see what's gonna happen.

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‫And it says, I'm learning for 8 hours and I work for 32 hours.

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‫Well, we have overridden it, and we just used the exact same method.

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‫So work.

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‫Same name.

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‫This one was not virtual and we overrode it.

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‫And here it's complaining.

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‫Or it's not really complaining, but it says that there is something not perfectly right.

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‫So that's perfect because it helps us to go to the next chapter where we talk about polymorphism, about

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‫overriding methods even further, because so far we've only used one approach, but there are multiple

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‫ones.

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‫So if I, for example, create a public new void work that will go ahead and create a new method for

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‫me.

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‫And well, in our case it does the same thing.

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‫But when it comes to polymorphism, this is going to have a huge impact onto our our program.

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‫So I hope you manage to build that.

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‫And it was just a different exercise, just a new exercise, another one for you to test again, whether

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‫you can handle that, whether you can create subclasses and just to get a better understanding of how

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‫classes or the base classes and deriving classes work together and how to build them and stuff like

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‫that.

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‫Great.

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‫So see you in the next chapter where we're going to go into polymorphism.