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Was it in lieu of a phone screen? A lot of companies do that now, and it's generally done for the same reasons as a phone screen. My company doesn't do this, bu

Was it in lieu of a phone screen? A lot of companies do that now, and it's generally done for the same reasons as a phone screen. My company doesn't do this, but we do phone screens for every developer, no matter how much experience they have. There are just too many crappy "senior" developers out there.

raverbashing 10y ago
A phone screen/coding exercise is ok to filter bad ones out (but not to pick good ones from)
- therein 10y ago
  Yeah, we use phone screens as a smoke test. It is disheartening seeing how many "Senior" Software Engineers with over a decade of experience fail to implement `bool isNumber(const char*)` that works for positive/negative integers and decimals. And these people somehow get past the filtering that our recruiters (large social network headquartered in the Bay Area) are supposed to perform. Honestly exactly for this reason, I've been feeling a lot less passionate about conducting interviews than I did when I started my current job.
  - NumberSix 10y ago
    Most senior software engineers with over a decade of experience never implement bool isNumber(const char *) for positive/negative integers and decimals. It is rare to need this and, if you do, either use a library or find it on Stack Overflow, in a book, or some other source. Implementing it is unnecessarily reinventing the wheel. One thing senior software engineers learn or should learn is not to reinvent the wheel. This is one of the problems with these types of questions, including the CS 101 type questions that often make up purported coding tests during hiring. In most cases, they do not test what practicing software engineers actually do.
    - hcho 10y ago
      The point of the question is to see if a candidate can glue a loop,an if statement and a bit of arithmetic together, on the spot. Failing to come up with an answer to such a question is generally symptomatic of lack of problem solving skills.
    - raverbashing 10y ago
      I disagree. If you can't code IsNumber at least for plain integers you shouldn't be touching code. Then work up to negative/decimal Yes, for a lot of problems you should go for stack overflow or a book. But this is a simple problem. SO won't have the solutions to all of your problems
      - NumberSix 10y ago
        As another commenter noted, for negative/decimal it is not so simple. That is why a highly experienced software engineer would look for an existing, fully debugged implementation rather than spend substantial time making sure all the corner cases are handled. In the context of an interview, it is highly likely a highly experienced software engineer will miss some of the corner cases. The exception would mostly be someone who has specifically studied and drilled on implementing isNumber(char * string) or specifically works in implementing these kind of functions which is rare. As I said there are libraries with these today.
    - NotSammyHagar 10y ago
      You are missing the point. The goal is to show you can do simple coding and design. The particular example is not necessarily something you'd do explicitly. It's like writing fizzbuzz.
  - MrQuincle 10y ago
    Tougher than it looks at first sight: * there is no length argument * localization, should it contain dots or commas? * the minus sign or a plus sign should be only at start * there should be only a single decimal separator * just a dot is not a number * just a minus or plus sign is not a number * empty string is not a number * there should be only a single minus or plus sign * there should be a minus OR a plus sign * let's assume something like .0 or 0. is allowed * let's assume 4E04 is not allowed (although it is a positive integer)
    - therein 10y ago
      Yup, those are exactly what we look for as well. And yes, you're correct at all of those assumptions. :)
      - closeparen 10y ago
        Does the candidate get to develop this code iteratively and test it, or is it a timed/whiteboard scenario?
        therein 10y ago
        They develop the code iteratively and test it while thinking out loud.
      - MrQuincle 10y ago
        This is a nice example of how much work goes into a good implementation: http://www.exploringbinary.com/how-strtod-works-and-sometimes-doesnt/ http://www.exploringbinary.com/how-strtod-works-and-sometime...
mkagenius 10y ago
> There are just too many crappy "senior" developers out there. In what ways do you find them crappy?
- cerrelio 10y ago
  I'd like to know too. I'm a senior dev with 10+ years of experience. I don't do interviews that require a coding portion. It's a little insulting to me. I know what a binary search tree is. I've never written one outside of college, because they're already implemented in the tools I use. I'm not going to waste my company's time doing freshman-year exercises. If I need to know a specific structure or algorithm, I have books filled with hundreds of them. I know how to use a book's index. I just assume any company that makes you code during the interview for senior positions is looking for a code robot. My skills have advanced beyond that point. I don't want to go back there.
  - garysieling 10y ago
    Does that mean you're looking for management type positions? It's been a while since I've interviewed, but I always thought at least a little bit of coding in an interview was good, because you know the company weeds out people who are lying about being programmers.
    - cerrelio 10y ago
      No, for development positions. If a recruiter can't weed out posers before a manager/developer talks to them, that recruiter should be dehired. To get jobs at my current and previous company, I just talked to the lead developer for 3+ hours. No coding necessary. I was quizzed on design patterns and given architecture problems, which I find more appropriate than FizzBuzz. Also, my alumni association is very useful for job hunts. I'll never go back to cold-calling or responding to LinkedIn solicitations again. I chat with an alumnus over coffee for a few hours, and twice it's resulted in job offers without the need for a formal interview.
      - 10y ago

raverbashing 10y ago

A phone screen/coding exercise is ok to filter bad ones out (but not to pick good ones from)

therein 10y ago
Yeah, we use phone screens as a smoke test. It is disheartening seeing how many "Senior" Software Engineers with over a decade of experience fail to implement `bool isNumber(const char*)` that works for positive/negative integers and decimals. And these people somehow get past the filtering that our recruiters (large social network headquartered in the Bay Area) are supposed to perform. Honestly exactly for this reason, I've been feeling a lot less passionate about conducting interviews than I did when I started my current job.
- NumberSix 10y ago
  Most senior software engineers with over a decade of experience never implement bool isNumber(const char *) for positive/negative integers and decimals. It is rare to need this and, if you do, either use a library or find it on Stack Overflow, in a book, or some other source. Implementing it is unnecessarily reinventing the wheel. One thing senior software engineers learn or should learn is not to reinvent the wheel. This is one of the problems with these types of questions, including the CS 101 type questions that often make up purported coding tests during hiring. In most cases, they do not test what practicing software engineers actually do.
  - hcho 10y ago
    The point of the question is to see if a candidate can glue a loop,an if statement and a bit of arithmetic together, on the spot. Failing to come up with an answer to such a question is generally symptomatic of lack of problem solving skills.
  - raverbashing 10y ago
    I disagree. If you can't code IsNumber at least for plain integers you shouldn't be touching code. Then work up to negative/decimal Yes, for a lot of problems you should go for stack overflow or a book. But this is a simple problem. SO won't have the solutions to all of your problems
    - NumberSix 10y ago
      As another commenter noted, for negative/decimal it is not so simple. That is why a highly experienced software engineer would look for an existing, fully debugged implementation rather than spend substantial time making sure all the corner cases are handled. In the context of an interview, it is highly likely a highly experienced software engineer will miss some of the corner cases. The exception would mostly be someone who has specifically studied and drilled on implementing isNumber(char * string) or specifically works in implementing these kind of functions which is rare. As I said there are libraries with these today.
  - NotSammyHagar 10y ago
    You are missing the point. The goal is to show you can do simple coding and design. The particular example is not necessarily something you'd do explicitly. It's like writing fizzbuzz.
- MrQuincle 10y ago
  Tougher than it looks at first sight: * there is no length argument * localization, should it contain dots or commas? * the minus sign or a plus sign should be only at start * there should be only a single decimal separator * just a dot is not a number * just a minus or plus sign is not a number * empty string is not a number * there should be only a single minus or plus sign * there should be a minus OR a plus sign * let's assume something like .0 or 0. is allowed * let's assume 4E04 is not allowed (although it is a positive integer)
  - therein 10y ago
    Yup, those are exactly what we look for as well. And yes, you're correct at all of those assumptions. :)
    - closeparen 10y ago
      Does the candidate get to develop this code iteratively and test it, or is it a timed/whiteboard scenario?
      - therein 10y ago
        They develop the code iteratively and test it while thinking out loud.
    - MrQuincle 10y ago
      This is a nice example of how much work goes into a good implementation: http://www.exploringbinary.com/how-strtod-works-and-sometimes-doesnt/ http://www.exploringbinary.com/how-strtod-works-and-sometime...

mkagenius 10y ago

> There are just too many crappy "senior" developers out there. In what ways do you find them crappy?

cerrelio 10y ago
I'd like to know too. I'm a senior dev with 10+ years of experience. I don't do interviews that require a coding portion. It's a little insulting to me. I know what a binary search tree is. I've never written one outside of college, because they're already implemented in the tools I use. I'm not going to waste my company's time doing freshman-year exercises. If I need to know a specific structure or algorithm, I have books filled with hundreds of them. I know how to use a book's index. I just assume any company that makes you code during the interview for senior positions is looking for a code robot. My skills have advanced beyond that point. I don't want to go back there.
- garysieling 10y ago
  Does that mean you're looking for management type positions? It's been a while since I've interviewed, but I always thought at least a little bit of coding in an interview was good, because you know the company weeds out people who are lying about being programmers.
  - cerrelio 10y ago
    No, for development positions. If a recruiter can't weed out posers before a manager/developer talks to them, that recruiter should be dehired. To get jobs at my current and previous company, I just talked to the lead developer for 3+ hours. No coding necessary. I was quizzed on design patterns and given architecture problems, which I find more appropriate than FizzBuzz. Also, my alumni association is very useful for job hunts. I'll never go back to cold-calling or responding to LinkedIn solicitations again. I chat with an alumnus over coffee for a few hours, and twice it's resulted in job offers without the need for a formal interview.
    - 10y ago