Ask HN: Have you ever needed to invert a binary tree at work?

What does that even mean? Putting it upside down? But that's just the exact same graph, so a no-op operation? Come to think of it, I wrote a plenty of no-op methods in my career...

0, but you need it to get work.

Just be pragmatic about it. The same way you've learned a lot of crap at school for nothing, do you expect that in the job market it would be any different?

The world is fucked up, the earlier you internalise this in yourself, the less you suffer.

I asked you to invert a binary tree because I was asked to invert a binary tree. My father was asked to invert a binary tree. My father's father was asked to invert a binary tree.

Charles Babbage asked Ada Lovelace to invert a binary tree before he agreed to let her work on his Analytical Engine.

In his famous resume, Leonardo claimed knowledge of "efficient methods of turning a bifurcated assembly of facts upon itself, and other procedures useful in the arts of arranging and displaying facts."

It's tradition.

https://en.m.wikipedia.org/wiki/Ada_Lovelace

https://duckduckgo.com/?q=resume+of+leonardo+da+vinci&t=fpas...

No, however, please note the following:

Companies, like customers, have requirements for their needs. If a company needs a potential employee to know how to invert a binary tree then it's in their right to find one.

In Google's case, as you're probably alluding to[0], although I might be mistaken, they've always had the reputation for seeking the best qualified people[1] for their work. I mean look at who's working for them - there's a lot of well-known people in their respective fields that are working for them.

Moreover, I think that the point of these tests is to help assess a potential employee's abstract thinking. And, probably, to understand one's thought process behind the solution - if there's one - to the given problem. (Which, by the way, might be helpful if you're trying to solve AI - something that's right up in Google's alley ;).

Despite the backlash over this, I believe companies will keep doing these types of tests for a long, long time. I don't think this is going away that easily. And I also think that, in the future, these tests might be done in a way you won't even know you're being tested for.

[0] - https://twitter.com/mxcl/status/608682016205344768

[1] - I understand that "best qualified" here might mean different things for different people, but you should take it literally, that is, people who are above the average in terms of abstract thinking. I suggest you read How Google Works[2], they've coined the term Smart Creative which is kind of(?) related to this.

[2] - https://www.howgoogleworks.net/