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Ancestors - Intro to Computer Science

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    The question we want to think about is
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    how you could define who your ancestors are. The
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    way to think about ancestors. Well, here's you.
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    Hopefully, you're smiling, because you're enjoying learning about recursive
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    definitions. And you had some parents. Let's assume
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    you had two. And we won't assume whether of
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    not your parents are smiling, but let's hope
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    at least one of them is. And your parents
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    were your ancestors, but they're not all
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    of your ancestors. Your parents had parents, as
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    well. These are your grandparents. Grandparents are always
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    happy. So, they're all smiling. And your grandparents,
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    well, they also had parents. Those would
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    be your great-grandparents, and so forth. And all
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    of these, except yourself, are your ancestors. So
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    our goal now is to define that precisely.
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    Can we come up with a definition that describes
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    exactly this same relationship, all the ancestors that you
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    have? So the question is, which of these is
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    the best definition of ancestors? And there are three
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    choices, the first has one rule, ancestor is replaced
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    by parent of ancestor. The second has two rules,
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    ancestor is replaced by parent, and ancestor is replaced
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    by parent of the ancestor. The third has three rules.
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    Ancestor is replaced by parent. Ancestor is replaced by parent
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    of parent. And ancestor's replaced by parent of parent of ancestor.
タイトル:
Ancestors - Intro to Computer Science
概説:

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Video Language:
English
Team:
Udacity
プロジェクト:
CS101 - Intro to Computer Science
Duration:
01:25

English subtitles

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