4 ms·

Are you kidding? reversing a string in your language of choice is far too trivial. If you can't do it you really aren't ready to be working in the industry.

by borplk 14y ago

cygwin98 14y ago
Out of curiosity, when the interviewer asks you to reverse a string in your language, say Ruby, are you supposed to use existing algorithms/methods built-in in that language, or to flip each character using a for-loop? In Ruby, it's really a single method called reverse will do the trick, i.e., "hello".reverse gives "olleh". I'm trying to make sense of the reason why such a question is asked.
- candybar 14y ago
  No, the expectation is that you'll use a loop or recursion. If you use an existing method/function, the interviewer will kindly ask you to implement that yourself. The general reason why such a question is asked is because interviewers don't have an infinite amount of time and there's no point in considering any candidate who can't do this. It's a way to weed out ridiculously bad candidates so that you can focus more on good candidates.
EnderMB 14y ago
It's not about whether they can do it or not. It's about why knowing a skill that will take even a non-developer ten seconds to Google makes someone incapable of functioning as a developer. More often than not the people that spout that kind of nonsense are twenty-something junior developers that read a bit of HN and have decided that they know better than everyone else about what makes a good programmer. Why would you test if someone can reverse a string if you're hiring someone to maintain and build on some shitty web app?
- candybar 14y ago
  It takes someone who doesn't speak English ten seconds to look up the past tense of the verb "bring" - this doesn't mean you'd want to hire as a journalist someone who seems to think the answer is "bringed" Doing a string reverse is so trivial that it's not about needing that skill, but rather what not being able to do that speaks about the candidate's general aptitude and skill level.
  - EnderMB 14y ago
    "Why would you test if someone can reverse a string if you're hiring someone to maintain and build on some shitty web app?" If that question can't be answered then your opinion on someones skill level is irrelevant. Also, if you've got time, answer the questions in my first post: "How old are you? Have you hired developers before? Truthfully, have you ever had to reverse a string under pressure at your current job."
    - candybar 14y ago
      Because anyone who can't do this almost certainly doesn't have the ability to program any software system well, some shitty web app or otherwise. You're not trying to fill out a remedial CS course in community college, you're trying to get someone to program real things real people use. The only way this question wouldn't be useful is if you had a good filter such that almost everyone who gets to that point would answer that question correctly. But apparently, this is not the case. There are people who fail such tests (despite apparently good paper qualifications and ability to talk BS). It's fairly important that you not let through such imposters. And yes I've hired people and all of them have had to answer much more complex algorithmic questions to get the job and all of them turned out to be competent. And "have you ever had to" questions are ingenuous - interview settings are never going to be replicated exactly in a work setting, unless your job is to go around to be interviewed for different jobs. Good interview questions don't simulate work setting - they extract most critical work-relevant information about the candidate without wasting time.
      - EnderMB 14y ago
        "Because anyone who can't do this almost certainly doesn't have the ability to program any software system well, some shitty web app or otherwise. You're not trying to fill out a remedial CS course in community college, you're trying to get someone to program real things real people use." So...I'm hiring someone that can reverse a string because this demonstrates that they can program real things that real people use? "And yes I've hired people and all of them have had to answer much more complex algorithmic questions to get the job and all of them turned out to be competent." Out of interest, what did this job entail? I assume that you quizzed them on their knowledge of basic algorithms because they are required to write them, right?
- DanBC 14y ago
  Being able to web-search the answer is good. Being able to recognise the correct answer in the sea of dross that is search engine results pages is better. Being able to take the correct answer, and adapt it to what you need, and plugging it into what you already have, is best. Do you really want to employ people who say they have X years of experience doing something but who cannot do a very simple task in the choice of their language? That's not a stupid trick gimmick question - there's no "gotcha" there. Perhaps we're getting caught up on the specific "reverse a string". Substitute that for something relevant to maintaining and building on a shitty web app.

Are you kidding? reversing a string in your language of choice is far too trivial. If you can't do it you really aren't ready to be working in the industry.

by borplk 14y ago

Are you kidding? reversing a string in your language of choice is far too trivial. If you can't do it you really aren't ready to be working in the industry.

cygwin98 14y ago

Out of curiosity, when the interviewer asks you to reverse a string in your language, say Ruby, are you supposed to use existing algorithms/methods built-in in that language, or to flip each character using a for-loop? In Ruby, it's really a single method called reverse will do the trick, i.e., "hello".reverse gives "olleh". I'm trying to make sense of the reason why such a question is asked.

candybar 14y ago
No, the expectation is that you'll use a loop or recursion. If you use an existing method/function, the interviewer will kindly ask you to implement that yourself. The general reason why such a question is asked is because interviewers don't have an infinite amount of time and there's no point in considering any candidate who can't do this. It's a way to weed out ridiculously bad candidates so that you can focus more on good candidates.

EnderMB 14y ago

It's not about whether they can do it or not. It's about why knowing a skill that will take even a non-developer ten seconds to Google makes someone incapable of functioning as a developer. More often than not the people that spout that kind of nonsense are twenty-something junior developers that read a bit of HN and have decided that they know better than everyone else about what makes a good programmer. Why would you test if someone can reverse a string if you're hiring someone to maintain and build on some shitty web app?

candybar 14y ago
It takes someone who doesn't speak English ten seconds to look up the past tense of the verb "bring" - this doesn't mean you'd want to hire as a journalist someone who seems to think the answer is "bringed" Doing a string reverse is so trivial that it's not about needing that skill, but rather what not being able to do that speaks about the candidate's general aptitude and skill level.
- EnderMB 14y ago
  "Why would you test if someone can reverse a string if you're hiring someone to maintain and build on some shitty web app?" If that question can't be answered then your opinion on someones skill level is irrelevant. Also, if you've got time, answer the questions in my first post: "How old are you? Have you hired developers before? Truthfully, have you ever had to reverse a string under pressure at your current job."
  - candybar 14y ago
    Because anyone who can't do this almost certainly doesn't have the ability to program any software system well, some shitty web app or otherwise. You're not trying to fill out a remedial CS course in community college, you're trying to get someone to program real things real people use. The only way this question wouldn't be useful is if you had a good filter such that almost everyone who gets to that point would answer that question correctly. But apparently, this is not the case. There are people who fail such tests (despite apparently good paper qualifications and ability to talk BS). It's fairly important that you not let through such imposters. And yes I've hired people and all of them have had to answer much more complex algorithmic questions to get the job and all of them turned out to be competent. And "have you ever had to" questions are ingenuous - interview settings are never going to be replicated exactly in a work setting, unless your job is to go around to be interviewed for different jobs. Good interview questions don't simulate work setting - they extract most critical work-relevant information about the candidate without wasting time.
    - EnderMB 14y ago
      "Because anyone who can't do this almost certainly doesn't have the ability to program any software system well, some shitty web app or otherwise. You're not trying to fill out a remedial CS course in community college, you're trying to get someone to program real things real people use." So...I'm hiring someone that can reverse a string because this demonstrates that they can program real things that real people use? "And yes I've hired people and all of them have had to answer much more complex algorithmic questions to get the job and all of them turned out to be competent." Out of interest, what did this job entail? I assume that you quizzed them on their knowledge of basic algorithms because they are required to write them, right?
DanBC 14y ago
Being able to web-search the answer is good. Being able to recognise the correct answer in the sea of dross that is search engine results pages is better. Being able to take the correct answer, and adapt it to what you need, and plugging it into what you already have, is best. Do you really want to employ people who say they have X years of experience doing something but who cannot do a very simple task in the choice of their language? That's not a stupid trick gimmick question - there's no "gotcha" there. Perhaps we're getting caught up on the specific "reverse a string". Substitute that for something relevant to maintaining and building on a shitty web app.