Story to Share
Medium, in its own words, is "a place where everyone has a story to share and the best ones are delivered right to you." You might recall that CS50’s own blog lives at medium.com/@cs50.
So how does Medium know whether someone’s read a post already? Read a tale of code, dinner, and a favour with unexpected consequences to find out. The post’s a bit long, but odds are you’ll find it sufficient to read these sections, merely skimming or skipping the rest:
Answer the below in story.txt
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Questions
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(2 points.) Why doesn’t Medium just use an array to store, for each user, the unique identifiers of the posts that a user has already read?
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(2 points.) Why doesn’t Medium just use a linked list to store, for each user, the unique identifiers of the posts that a user has already read?
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(2 points.) Why doesn’t Medium just use a trie to store, for each user, the unique identifiers of the posts that a user has already read, effectively treating the identifiers like words in a dictionary?
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(4 points.) Why does Medium sometimes think a user has read some post, even though the user has not?
Debrief
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Which resources, if any, did you find helpful in answering this problem’s questions?
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About how long did you spend on this problem’s questions?