My logic is right but test cases are very hude numbers.... failed to evaluate...
You need to learn to avoid loops. You can use isprime on an array. In any case, your logic is wrong. You never test that b is prime.
As Guillaume pointed out, this solution doesn't test if the numbers in b are Mersenne primes, simply if they're less than 2^n-1, which is not the right criterion. Further, you concatenate the index of the loop (j, which goes from 1 to 1...), rather than a Mersenne prime to b.
Also, this problem is designed, as many of James's problems are, to fail by timeout unless vectorized solutions are used.
i have corrected the logic but plz can u tell me smthing about vectorized solutions...
u can also mail me on email@example.com
some tips: http://nl.mathworks.com/help/matlab/matlab_prog/techniques-for-improving-performance.html
While evaluating the solution, the server encountered an error caused by temporary unavailability of MATLAB Service. Wait a few minutes for the MATLAB Service to return, and then rescore.
Remove any row in which a NaN appears
Back to basics 1 - Saving
Right Triangle Side Lengths (Inspired by Project Euler Problem 39)
03 - Matrix Variables 6
Rumis Scorer 4
Calculator spelling - Numbers to Letters
Divisible by 15
Divisible by n, prime divisors - 11, 13, 17, & 19
Rule of mixtures (composites) - upper bound
Choose a web site to get translated content where available and see local events and offers. Based on your location, we recommend that you select: .
You can also select a web site from the following list:
Select the China site (in Chinese or English) for best site performance. Other MathWorks country sites are not optimized for visits from your location.
Contact your local office