Re: interview question on primes

On Tue, 26 Feb 2008 12:28:27 +1100, "Peter Webb"
<webbfamily@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:


"Digital Puer" <digital_puer@xxxxxxxxxxx> wrote in message
news:3bdc49e5-d202-491a-bde2-c7c31bee801f@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Got this on a software engineering interview question:
given two integers A and B, find all primes between them.

I basically wrote an initial function, bool isPrime(int i), which
loops over all numbers between 2 and sqrt(i) to see if i%num == 0,
in which case the number is not a prime. With this function, I then
loop between A and B, calling isPrime() on each value.

Any better ideas?

The "correct" answer is heavily dependent on the range of values of A and B,
and if this is all the question states, its a pretty poor question.

No, not really.

It's a real world question, not an academic one.

Moreover, the question was not a "take-home project". Presumably it
was expected to solved right then and there, at the interview.

Judgement is required here.

Of course, the applicant can always _ask_ the interviewer about the
range of values, but in my opinion, having to ask that question would
show a lack of common sense. The very fact that the range was not
specified, together with the implied time constraints of the
interview, should be enough for the applicant to opt for a clean,
simple, standard solution.

quasi
.

Relevant Pages

  • Re: interview question on primes
    ... given two integers A and B, find all primes between them. ... loops over all numbers between 2 and sqrtto see if i%num == 0, ... They can't assume that the applicant is a Number ... research project out of it, ...
    (sci.math)
  • Re: interview question on primes
    ... given two integers A and B, find all primes between them. ... loops over all numbers between 2 and sqrtto see if i%num == 0, ... was expected to solved right then and there, at the interview. ... situation (interview time, on the spot) calls for simplicity. ...
    (sci.math)
  • Re: interview question on primes
    ... given two integers A and B, find all primes between them. ... loops over all numbers between 2 and sqrtto see if i%num == 0, ... was expected to solved right then and there, at the interview. ... the applicant can always _ask_ the interviewer about the ...
    (sci.math)
  • Re: interview question on primes
    ... quasi wrote: ... given two integers A and B, find all primes between them. ... was expected to solved right then and there, at the interview. ... simple programming tasks during the interview. ...
    (sci.math)
  • Re: finding primes
    ... find all primes between them. ... I basically wrote an initial function, bool isPrime, which ... loops over all numbers between 2 and sqrtto see if i%num == 0, ... force (all the mentioned solutions in this thread are brute force) for ...
    (comp.programming)