
Ask HN: What's your favorite graph interview question? - mrburton
What&#x27;s your favorite interview questions related to graphs?
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asafira
If you were a graph, which would you be?

More seriously: do people think that any questions that require anything more
than DFS, BFS, and/or Dijkstra are reasonable to ask for most general software
engineering positions? (I appreciate specific positions might expect more)

Of course, trees are graphs too, and there are loads of tree questions --- I
guess I'd narrow my response down to questions regarding general graphs and
not just trees.

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kskbng
I think it's fine to expect engineers to know graph algorithms in terms of
what they do and when to use them, but knowing how to implement them on the
spot on a whiteboard is stupid. This one company had an interesting problem
that I identified quickly as an application of A* with some interesting edge
cases on top. Working through those cases and coming up with the heuristic was
clearly the main point of the interview, or so I thought. The interviewer
asked me to write out A* on the whiteboard...

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akhilcacharya
Paint fill is a great basic one.

A slight step up from that could be word search/boggle as it involves multiple
data structures (trie, etc).

Another good one is topologically sporting a dependency graph to get a list of
dependencies to install/operate on in order.

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imauld
The one that has to do with the work I'll be doing at the company. If I won't
be working on/with graphs what's the point of asking the question?

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chrisbennet
“If we asked you to sell more ads, which graph would you choose?”

Follow up: “Which graph would be better at tracking and monitizing our users?
Preferably, it would be optimized for lowest memory usage while also not
letting our users know how we exploit their trust in us.”

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Eridrus
I also have reservations about algorithms questions as a useful interview
filter, but my favourite that I have been asked is "How would you delete a
tree using a fixed amount of memory? i.e. no recursion or other dynamic
structures".

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money_talks
Huh? Deletion has different meanings depending on context. What do you mean by
delete, exactly? What language? How is the tree stored?

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wingerlang
As far as I've read, sometimes questions are ambiguous to see how the
interviewee proceeds with the problem, if they ask relevant questions.

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itamarst
None. Asking about algorithms isn't a good way to assess candidates (unless
they will be writing graph algorithms, which as it turns out doesn't happen
very often).

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davidjnelson
As an interviewer or interviewee?

For a take home interview, variations on 8 queens can be interesting since
they utilize dfs and backtracking.

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SamReidHughes
I don't think I've ever encountered one.

