Counterpoint to many responses here - when I have interviewed people, it’s a really positive signal if the candidate says they have already seen a problem- the we can move onto something more interesting! Not solving does not mean failure either. As a candidate myself I always mention if I have seen similar problems, such as finding primes - real example, and I was hired on that loop at Microsoft!
On the other hand, if I heard that a candidate had not mentioned they had the same question twice, or later let it be known they already knew the answer, I would lose a lot of trust in them.
Be honest; it’s more likely you will be hired by honest people.
IMO the key thing is that interviews have a heavy component of randomness.
The question your interviewer selects (both topic and difficulty), how the interview performs as far as presenting the question/giving hints, how the interviewer is feeling, any biases the interviewer might have, and so on.
You can of course 'increase your surface area for luck' by studying the questions/topics a company tends to ask, being an interviewee who comes off as well qualified.
But, if you get an interviewer who is in a bad mood, if your interview isn't competent or paying attention, etc. then you're just screwed.
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I say this because the OP was honest and failed; you were honest and were hired. There's no 'secret' to getting in. It is a combination of:
1. Being a competent engineer (or student)
2. Putting in the time to study, leetcode, practice, etc.
I'd preface the solution and the key point before mentioning that I'd seen this problem before and then further ask if they still want me to code up the solution. This eliminates the case that I, the interviewee might be bluffing. Also they might just be interested to know if you can think on your feet by then adding a twist later. who knows not my call.
It would be dumb if the next one they throw at me is one i've also seen or is ridiculously hard for an interview. Then i'd question the value of my honesty.
> As a candidate myself I always mention if I have seen similar problems, such as finding primes - real example, and I was hired on that loop at Microsoft!
Normally I'm completely in favour of being honest about this (and would almost certainly do it myself), but in the case of something as common as "finding primes" I'd think it's OK to just do it. Does any interviewer really expect that the majority of candidates haven't look at basic prime finding and primality checking algorithms?
How many devs above 40 do you think still do leetcode to keep themselves entertained, especially if their daily work is doing CRUD stuff between corporate meetings?
We're specifically talking about people who are interviewing for jobs - I'd expect a lot of them to have done leetcode before the interviews.
Also: when we think about whether we've seen a problem or not before (in order to be honest during an interview), presumably this includes all problems we have a significant memory of, not just problems we've seen recently.
Really, do you expect folks to dust off their algorithms and data structures from 30 years ago, instead of what they have been doing the last decade on the job?
Love to know how many do build bridges, repair cars,..., on their spare time for job interviews.
Yeah, it's weird (to me and you at least) why people bother quizzing industry veterans. After 10 years in the workforce you should be able to talk shop about various experiences you had at work (NDA permitting) and drop down to technical details where appropriate. Yet some companies or interviewers insist on techniques that could be replaced with asking the potential hire to eat boogers on camera for a stronger signal of what they're actually looking for.
On the other hand, if I heard that a candidate had not mentioned they had the same question twice, or later let it be known they already knew the answer, I would lose a lot of trust in them.
Be honest; it’s more likely you will be hired by honest people.