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In Defense of LeetCode Interviews

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Re: In Defense of LeetCode Interviews

#71
post #70

Earlier quoted context omitted.

This was basically my experience in college too. There was no time to understand something, and tests didn't test your understanding. If you tried to solve a proof for the first time you'd run out of time and fail. You just had to grind homework and book questions until you could shit them out in 5 minutes each.

That's an odd complaint. The time to solve a proof for the first time is when you're doing your homework. The course work is supposed to make you practice until your brain can easily pick up the recurring patterns. Sure, if the course is very poorly designed or the student is very unmotivated, they may end up just memorizing everything while somehow avoiding understanding anything. But in real life, when someone says…

> That's an odd complaint.

No it's not. I'll make it simpler. If you know the material really well but haven't memorized the problems, you will test poorly. If you memorize the problems and have no real understanding of the material, you will test well. This is obviously the opposite of what you want to test.

Re: In Defense of LeetCode Interviews

#72

Aren't there supposed AI tools out there for cheating on these standardized tests?

There are, but they are easy to detect

In my experience, I just need the aha hint and I'm usually good. When I looked them up later I was slapping my hand on my head. How do you detect that?

Re: In Defense of LeetCode Interviews

#73
post #6

Leetcode is just a proxy for an IQ test. That's it. If you can study up and do well on leetcode, then you're smart. People getting hung up on how realistic the questions are, or whether you ever need to implement X data structure are confused. Fact is that no job can give a reasonable test for how it is to work there short of working there. There's team dynamics, developer / project fit, etc etc. All you can ever do…

Actually - “how many golf balls fit into a VW Beatle” is a better proxy.

Those are called Fermi questions.

https://en.wikipedia.org/wiki/Fermi_problem

Re: In Defense of LeetCode Interviews

#74
post #34
post #6

Leetcode is just a proxy for an IQ test. That's it. If you can study up and do well on leetcode, then you're smart. People getting hung up on how realistic the questions are, or whether you ever need to implement X data structure are confused. Fact is that no job can give a reasonable test for how it is to work there short of working there. There's team dynamics, developer / project fit, etc etc. All you can ever do…

I wish they'd just give IQ tests then.. I do just fine in those (~140) but not a leet coder at all.

IQ tests are known to encode cultural biases. DEI troubles and possible lawsuits down that path!

Re: In Defense of LeetCode Interviews

#75
post #57

I have always seen LeetCode problems as effectively hazing rituals in a job interview setting. A high pressure interview situation simply won’t bring out peak problem-solving capabilities in many people. At best you get some superficial insight into someone’s problem solving methodology, but at worst you filter out otherwise excellent fits for not being able to solve an ultimately inconsequential problem under pressu…

The thing is, all these arguments can apply to any test you do during an interview. It is always under pressure, and it will always be incomplete. You will never know for sure before you actually hire the candidate. If the interview for a coding job doesn't involve actual coding, how do you know that the candidate can code? What you may get are people who are just really good at selling themselves. Maybe a good fit f…

Do not let the perfect obstruct the useful.

A FizzBuzz coding test - which is also imperfect - will weed out those who cannot code, and without the false negatives from LeetCode.

Programming is far more than writing code. Do you test their documentation skill? Their ability to work with others? To fix someone else's code? To identify and resolve ambiguities in the spec? To estimate development time?

Is the additional time needed for a LeetCode test over a FizzBuzz test worth the time taken from evaluating these other factors?

Re: In Defense of LeetCode Interviews

#76

If you hire using LeetCode, you will surround yourself with people who enjoy blogging about LeetCode in their free time. LeetCode was never about LeetCode, it was always a stand in for culture. It's now a signal for baseline compliance. That's generally good for companies that require mostly operationalists. The problem is that anyone can learn to leetcode. If you're interested in doing something new and not just war…

> The problem is that anyone can learn to leetcode. If you're interested in doing something new and not just warehousing CS lawyers, you're gonna have to ask better questions than that.

I think the problem is that everyone thinks they can ask better questions and almost none of those people are qualified to judge their interviewing competency or have data to back themselves up. Every company has its own special interview techniques that it's convinced will lead to the best possible outcomes when those only demonstrably lead to the current staffing. To question any of that means pointing fingers at pretty much everyone and that's a political non-starter.

Re: In Defense of LeetCode Interviews

#77
post #75
post #57

Earlier quoted context omitted.

The thing is, all these arguments can apply to any test you do during an interview. It is always under pressure, and it will always be incomplete. You will never know for sure before you actually hire the candidate. If the interview for a coding job doesn't involve actual coding, how do you know that the candidate can code? What you may get are people who are just really good at selling themselves. Maybe a good fit f…

Do not let the perfect obstruct the useful. A FizzBuzz coding test - which is also imperfect - will weed out those who cannot code, and without the false negatives from LeetCode. Programming is far more than writing code. Do you test their documentation skill? Their ability to work with others? To fix someone else's code? To identify and resolve ambiguities in the spec? To estimate development time? Is the additional…

I actually never did LeetCode interviews, but I did some competitive programming, same idea.

And it tests more useful skills than FizzBuzz. I wouldn't recommend hard questions, as they usually require techniques that are not very useful for most jobs and that you have to specifically train for (ex: dynamic programming). But for easy to medium questions, in my experience, the bottleneck is usually misunderstanding the problem, and simple bugs like typos, off-by-one, reversed conditions, etc...

Understanding of the problem relates the the ability to read a spec correctly, and the ability to identify and resolve ambiguities is related. And if you can fix your own bugs, it also helps when fixing others.

Of course, it doesn't test everything, particularly not teamwork (I mean, it is similar to competitive programming, the opposite of teamwork), but it was never meant to, other parts of the interview can do that.

As for documentation, I think writing skills are important and undervalued. I mean it in the traditional sense, like writing novels. We could have candidates write essays, but like LeetCode, people will complain. I will, because I suck at this, but I understand the value. By the way, I find that LLMs help a lot for this, language models, are, after all, really good at language, especially technical writing that is more formal than creative writing. Of course, the LLM require guidance, but once it gets the technical part right, I find the writing is pretty solid.

Re: In Defense of LeetCode Interviews

#78

Earlier quoted context omitted.

I don't try to add any pressure, but going on call will require some resilience from each team member.

As long as you don’t wake me at 3AM to rotate a red-black tree, or find the median of two sorted arrays we should be good

I must remember to ask how many times those problems happen in company's code base in next interview. Or whatever they ask. And if it is more than one, ask if they have libraries for it... You know good development practises and all.

Re: In Defense of LeetCode Interviews

#79

I have always seen LeetCode problems as effectively hazing rituals in a job interview setting. A high pressure interview situation simply won’t bring out peak problem-solving capabilities in many people. At best you get some superficial insight into someone’s problem solving methodology, but at worst you filter out otherwise excellent fits for not being able to solve an ultimately inconsequential problem under pressu…

I was looking at the Meta interview guide and it says: > Let us know if you’ve seen the problem previously and also: > In your tech screen, you’ll be asked to solve two problems in roughly 35 minutes. Practice coding solutions to medium and hard problems in less than 15 minutes each to help you be ready for the constraints during the interview. The only way I could solve two problems in 35 minutes is if I've seen the…

Here is a story about a problem in applying this approach more broadly.

A local tech recruiting company asked our Python user group to try out their new "fun" programming challenge used to evaluate and rank candidates.

We had an hour. I didn't like the problem, so ended up helping and chatting with others in the user group. Then after 45 minutes I realized there was a game theoretical best solution easily implemented using recursion and memoization.

While I was able to implement it in time, it did not win.

Further analysis later showed that the game play was too short to rank any strategy reasonably. More specifically, the winner was strongly based on player order, not strategy.

In other words, the tech recruiting company's new evaluation tool was total bunkum.

I wrote it up and let them know. I don't know what they did with that product.

In any case, it took me more than 35 minutes to solve.

Re: In Defense of LeetCode Interviews

#80
post #74
post #34

Earlier quoted context omitted.

I wish they'd just give IQ tests then.. I do just fine in those (~140) but not a leet coder at all.

IQ tests are known to encode cultural biases. DEI troubles and possible lawsuits down that path!

No more than leet code, these are spatial and logic tests with no cultural or social questioning, unlike the leet code questions.
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