Lightning Talk: How to Win at Coding Interviews - David Stone - CppCon 2022

cppcon.org/
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Lightning Talk: How to Win at Coding Interviews - David Stone - CppCon 2022
github.com/CppCon/CppCon2022
5 minutes of preparation is plenty to beat any coding interview.
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David Stone
David Stone has worked on autonomous vehicles, large-scale distributed systems, and now works developing software for high-frequency trading. He is a member of the C++ Standardization Committee, where he chairs the Modules Study Group (SG2) and is the vice chair of the Evolution Working Group (EWG).
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#cppcon #programming #coding

[@EgD996]

I really like this guy! Am I watching a stand-up comedy?

[@kodirovsshik]

What a great talk, I wish there were more like this one!

[@David-fn1rd]

Thanks!

[@khatdubell]

@@David-fn1rd Everyone knows interviews are testing for the wrong things.
The real question is, what's the solution?

[@David-fn1rd]

@@khatdubell Great question. I'm considering that for a full-length talk this year -- how we should be interviewing.

[@JohnDlugosz]

You can find a guy who promotes std::rotate as the solution to everything.

[@ChrisCox-wv7oo]

@@JohnDlugosz Sean Parent : czcams.com/video/sWgDk-o-6ZE/video.html

[@yuurishibuya4797]

Awesome, I love lighting talks, they pack the punch!

[@Sychonut]

Interviews at big tech is like a strange mating ritual.

[@HaoZhang88]

It is pretty fun watching this talk!

[@gustavob.7957]

that is actually great. simple but really valuable

[@Bbdu75yg]

Give us more talks like that !

[@zhongchu3325]

But leetcode 229, majority element II requires constant space. In this case, you are not allowed to use hash map. If hash map is allowed, this is simply an easy level problem. In a real code interview, the interviewer will definitely ask you to think of a solution using constant space. It won't be that easy....

[@HelloSpyMyLie]

Bruh he said use the Booyer Moore voting algorithm

[@user-ig8ut3zi4z]

LeetCode style interview questions don't measure how good the interviewee is in C++ or software engineering. It only measures how good they are at solving LeetCode style problems.
If all you do in your company is solving LeetCode problems, then hire via this broken method. You will be fine.

[@JohnDlugosz]

It's only one of the skills needed. When implementing something, a "step" will boil down to something like that : find something, organize something, count something, etc. Business logic usually falls into this category.
Now we test two skills: can you do that efficiently, and can you actually write code that works (write fluently)?
But that's not Software Engineering.
I'd say the best guide to testing is to test candidates on the stuff you do all day, every day. Well, strip out "Sit through meetings".

[@etherstrip]

@@JohnDlugosz Actually, no need to strip it out. After all, an interview is a meeting too.

[@gizigus055]

It's worse than that. Most of these big companies cannot force candidate to do the interview in a specific language. It's part of the recruitment process. So technically you can get a C++ job by doing a Leetcode interview in Python. It makes absolute no sense but this is the way it has become. It all boils down to how good you are at Leetcode.

[@joachimjoyaux179]

Excellent !

[@deeplearningpartnership]

Cool advice.

[@gokulram4950]

Awesome...

[@Shakephobiaful]

The last sentence is the most important one. Great talk 👍

[@qazarl]

Haha brilliant!

[@ohwow2074]

People sometimes forget that unordered containers are faster when it comes to searching. Great talk nonetheless.

[@vladimirkraus1438]

In reality they are usually not. Their only benefit is that they scale well for large amounts of data. But for smaller amounts they are usually much slower than a linear search in a plain stupid vector. It is always good too discuss this with the interviewer. What is the expected amount of data? Are we optimizning for speed or do we want a scalable solution? The fact that you know pros and cons of various containers is what will will impress the interveiwer probably more that he solution itself.

[@ruadeil_zabelin]

Most technical interviews are testing the wrong thing. You know you're going to get the wrong people when you give them homework. Why? Because only people that really need the job badly will try their hardest at them. People that know they're good enough will just try somewhere else and not bother.

[@vladimirkraus1438]

Sometimes you prefer people who are actually interested in the job than superstars with inflated ego.

[@gursewaksingh2146]

Like for 3rd question, most of the interviewers wants candidate to write their own algorithm.

[@habibahmedawan]

oh boy😀

[@vladimirkraus1438]

You should also show that you think ahead and are able to generalize. When given the first task finding the numbers which occur more than 1/3 of time, you should ideally create a solution in which 3 would be a runtime argument passed to the function. Unless it is a severe performance hit, in which case you should discuss this with the interviewer and only in that case decide to pass the value as compile time param. Also in the second task, you should ideally generalize the number of arrays and the required frequency as runtime args. If you just hardcode the number of arrays, your solution is not flexible in anticipation of future changes of requirements.
In short: seniors and experts should always think in general and abstract terms and anticipate future changes because they have seen so many. And always discuss the task presumptions before you start working on a solution. Show that you consider multiple solutions and you are able to tell the pros and cons.

[@tetsuoshiva]

Or : "How to interview when they liked your CV and it's just a formality".

[@shrekistlieben]

No no no ... Hash map is like for idiots . .. Lee Vodkatrubac can use a Travelling Fenwick Heap to solve it in O(1) and 3 lines of code

[@zz-oq2dt]

Are u kidding me?

[@sunnyshivam4782]

Great Idea