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Comment by RubenSandwich | Hacker News Reader

It sounds like the old programming interview questions: "Why are sewer covers round?", etc. They sound like they promote critical thinking, but really they just confuse the applicants. If you want to know how someone thinks, ask them to solve a problem step by step.

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Such questions are usually shibboleths for cultural and social affinity, rather than objective attempts to test critical thinking and logic.

An upvote for using the word "shibboleth."

> "Why are sewer covers round?"

Because sewer access holes are round.

Because the manufacturer was cutting corners. ;-)

I read once that "Wendy's restaurants" used square burgers instead of round because they "don't cut corners".

http://www.businessinsider.com/why-are-wendys-burgers-square...

i only know from learning about it, but round manhole covers prevent them from falling through the hole by consisting of a curve of constant width. Another example is the Reuleaux Triangle which is a viable shape for manhole covers. https://en.m.wikipedia.org/wiki/Reuleaux_triangle

not exactly a great logic question

The problem I have with this question is that it’s based on false pretenses. Plenty of manhole covers are not round.

Cool! I didn't know this was a thing, but I came up with the same solution independently when asked this question.

It also makes a wheel that has a constant tangent from the ground (not a constant axel point) as it turns.

Asking them to solve a problem step by step is great to learn whether that person is good at explaining the solution step by step. It is not about internal thought process you use to come up with solution.

Well, they have to at least be able to solve the problem, and being able to explain a solution is an important skill in its own right. Unless you are researching thought processes, or you are a Hardy working with a Ramanujan, the distinction you are making does not matter a whole lot.

I strongly disagree. If that happens then the interviewer is not doing their job.

You don't ask the applicant to solve and then explain, you ask them to solve and think aloud while they do it. If this doesn't come naturally to the candidate, which is totally fine, you must ask questions, suggest doubts, propose alternatives or request clarifications to encourage thinking aloud.

If you realize the candidate already knew the solution and is in fact just explaining it, then you have failed to prepare a sufficiently interesting question, and must come up with another.

I was always pretty good at these questions, honestly enjoyed them and I would never tell you my actual thought process. Of course I would answer questions (which are basically fun side quests), but especially if you interrupt me with them, you are not getting anything remotely resembling my thought process. You have me answering your questions and my thinking+behavior are heavily influenced by them and by what I see in socially appropriate behavior.

Sounds totally reasonable because 95% of the time software developers simultaneously write code and speak loudly about what they're doing at each step, while some timer is ticking in the background. Oh, wait...

The are squared sewers holes all around the world. At least, in front of my house, next to workplace and I encountered multiple others on my way between work and home today.

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