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An Algorithm for Passing Programming Interviews (2020)

malisper.me

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Re: An Algorithm for Passing Programming Interviews (2020)

#71

Post by kache_ »

diehunde wrote: post #48
arduinomancer wrote: post #5

Interviews are really a dumb game these days so if you want to really game it you can go with a statistical approach: * Practice questions by company on LeetCode, sort by frequency of last 6 months and work down the list, do maybe 75-100, the list updates once a week * Search for the company on the LeetCode forums and sort by most recent. If a question is not on LC yet it will likely get posted there, so you can get…

Many people say this. But the reality is that solving 100 LC questions and actually understand the solution enough to solve a variation of the problem is a lot of work. Especially if you are working full-time. I wouldn't call that "game it", just usual study and hard work.

When gaming it is just passing by studying, a repeatable process that anyone (with a CS degree) can do, just means the interview process is quite well designed.

The interview process is a test of endurance, not intelligence. And it should be exactly that, since software engineering is mostly an exercise of endurance and focus.

Every time a friend of mine QQs about failing a FANG interview, I give them the study prescription that worked for me. The reaction is always the same: they don't do it. If you can't get past these interviews, you probably won't make it past a year in these high performance companies anyways. Because you actually have to exhibit the same work ethic that interview studying requires.

Re: An Algorithm for Passing Programming Interviews (2020)

#72

Post by malisper »

Supermancho wrote: post #54

The anagram solution leaves the actual hard part unfinished^. Also, to solve in O(n) you need a bit array (or a database like Postgres that can do an XAND on a string). > Sort the characters of the words alphabetically. Since anagrams are all made up of the same letters. This will give us the same string for any pair of words that are anagrams of each. Correct. > Produce a dictionary of the number of times each lette…

> "Produce a dictionary of the number of times each letter occurs in each word." is heading the wrong direction. You want an encoding that does not care about the number of times each letter occurs in each word.

How so? "aab" is an anagram of "baa", but they are not anagrams of "ab".

Re: An Algorithm for Passing Programming Interviews (2020)

#73

Post by troutwine » 

  There’s also two additional programming techniques you should be aware of:
  * Dynamic Programming
How often do folks here use dynamic programming techniques in their professional lives? My own niche is systems programming. Dynamic programming is an important technique, sure, but given how rarely I see it used in practice compared to, say, statistical estimation it feels very overrepresented in interviews. But, maybe that's my own niche being unusual.

Re: An Algorithm for Passing Programming Interviews (2020)

#74

Post by kadoban »

netizen-936824 wrote: post #66
mrfusion wrote: post #56

Earlier quoted context omitted.

I’ve gotten interview questions I’d recently solved and my problem was it was too easy. I had trouble acting like it was the right amount of struggle. Is there a trick for that?

Why would you want to seem like you're struggling?

The interviewers are ideally trying to get a sense of how you think through problems, not just that you can spit out an answer you know. At least that's what they say.

Re: An Algorithm for Passing Programming Interviews (2020)

#75

Post by lordnacho »

Frost1x wrote: post #67
posharma wrote: post #15

Earlier quoted context omitted.

You've to be a genius to solve a "hard" unseen leetcode problem in 15 mins correctly. Facebook is notorious at expecting candidates to regurgitate solutions to problems in 15 mins. Intelligence plays a lesser role than exhaustive and painful practice which involves solving the same problem multiple times. It's a full-fledged examination that expects you to excel while being constantly watched and judged.

>It's a full-fledged examination that expects you to excel while being constantly watched and judged. and interrupted, frequently, because that's also perfectly normal. It's comical how this industry now thinks these arcane and often quite difficult DS&A interview question processes are reasonable and how it's been so normalized people just study this for weeks before applying to a new position, sacrificing evenings…

Yeah but it's a "how much do you want this job?" test. Which is not necessarily crazy, if you want to retain people in the firm it makes some sense to have them feel they worked hard for it, plus that they might not get through the eyes of the needle next time.

Re: An Algorithm for Passing Programming Interviews (2020)

#76

Post by kadoban »

mrfusion wrote: post #56
arduinomancer wrote: post #5

Interviews are really a dumb game these days so if you want to really game it you can go with a statistical approach: * Practice questions by company on LeetCode, sort by frequency of last 6 months and work down the list, do maybe 75-100, the list updates once a week * Search for the company on the LeetCode forums and sort by most recent. If a question is not on LC yet it will likely get posted there, so you can get…

I’ve gotten interview questions I’d recently solved and my problem was it was too easy. I had trouble acting like it was the right amount of struggle. Is there a trick for that?

Just go through the steps out loud, start with a really naive solution, say what's wrong with it, go on to the next. You can usually go through at least 3 levels of that. Also spend some time verifying the specification of the problem, ask about any potential edge cases. If you really know the problem well, go into maybe some extensions of it or harder versions.

Re: An Algorithm for Passing Programming Interviews (2020)

#77

Post by malisper »

dnpp123 wrote: post #61
malisper wrote: post #52

Earlier quoted context omitted.

> The solution described in the article is likely to be extremely wasteful in both time and memory, by allocating a queue entry for each call, and then O(n) scanning and dropping stale entries on each successive call. Even if n elements are scanned in the the worst case, the expected time it takes to perform such a scan is O(1). This is because we perform a scan on each insertion and O(n) elements are deleted in a sc…

> That means the number of elements scanned is proportional to the number of elements inserted. And the number of elements inserted is in the worst case N, hence the proposed solution has a worst case complexity of O(N)?

> hence the proposed solution has a worst case complexity of O(N)?

Worst case yes, but the question is concerned with the average case.

Re: An Algorithm for Passing Programming Interviews (2020)

#78

Post by gopher_space »

ldjkfkdsjnv wrote: post #10

Before people start complaining about leetcode and how it doesnt exemplify skills: its a proxy for a combination of: intelligence and how hard you are willing to study the computer science knowledge shown is just a bonus EDIT: One last thing to throw in, its pretty clear that theres a correlation between the top software companies and how hard their leetcode interviews are. You can claim all you want it doesnt work,…

It's a great way for second-raters to grind their stats instead of actually building something.

Re: An Algorithm for Passing Programming Interviews (2020)

#79

Post by rrradical »

For the second problem, I had an idea for a different hash function. Basically map each letter to a prime number (e.g. c = 5, d = 7) and then multiply the values in a word together. I guess depending on the length of the words it might overflow. But I thought it was interesting.

Re: An Algorithm for Passing Programming Interviews (2020)

#80

Post by netizen-936824 »

kadoban wrote: post #74
netizen-936824 wrote: post #66

Earlier quoted context omitted.

Why would you want to seem like you're struggling?

The interviewers are ideally trying to get a sense of how you think through problems, not just that you can spit out an answer you know. At least that's what they say.

So does struggle equate to working through a problem? I don't think it does.
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