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Thank you We sneak and here's your shmoop du jour

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brought to you by super class is not to be

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confused with supper classes But if you're already wearing your

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lobster bin well leave it all right This question is

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based on the following class hierarchy diagram this one Note

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that in open air own denotes an inheritance relationship and

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a closed aero denotes a composition relationship though which of

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the following is correct And here the potential answers has

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there Mike all right well here we have a question

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about a pretty basic class hierarchy structure whenever something like

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this crops up It's important to remember that there are

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two kinds of relationships Glasses can have inheritance and composition

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Except those two words are needlessly convoluted and actually pretty

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vague when you think about it So they often get

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referred to as isa and has a relationship when two

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classes related one either is the other or has the

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other okay Subtle but important Consider this The class limb

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is related to the classes of arm and leg An

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army is a limb just a more specific kind of

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limb and sore legs A foot is not a leg

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But they're still related instead of leg has a foot

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got it Give yourself a hand We've got a leg

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up and are ready to go toe to toe with

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questions So here we have our hierarchy of classes and

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we can see that north american country is a country

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is seeing yousa as our european country and asian country

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East asian country is an asian country too They're our

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inheritance relationships and our denoted by the downward open arrows

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these things state is not a north american country However

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this is a has a situation where north american country

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has a state north american country can also have a

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territory or province thes composition relationships air denoted by upward

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close aargh and we're being asked which of the following

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is correct so let's look alright option a says north

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american country is a super class of state not quite

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north american country has a state so it's a composition

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relationship rather than an inheritance relationship No super classes around

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here option b r v says there is a has

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a relationship between asian country and east asian country We'll

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not it off east asian country is an asian country

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is this one out of here Option c there is

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a has a relationship between north american country and province

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Yes the diagram pretty clearly shows that's the case upward

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arrow and everything Yep let's Check the others though right

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option d says state is a subclass of country well

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no countries way up here in states way down here

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So north american country has a state but it's not

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the same thing He makes almost the same error reaching

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all the way across The diagram in claiming country has

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a territory well no not at all North american country

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has a territory but country doesn't That means sea is

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definitely our answered North american country has province and ice

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hockey and mounties and ryan gosling's from there and polar

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bears and kids in the hall and the roots and

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half a niagara falls And that life is a highway 00:03:27.27 --> [endTime] song

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