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 firstname.lastname@example.org
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.
Tic Tac Toe FTW
Bottles of beer
Replace multiples of 5 with NaN
Area of a circle
How many Fibonacci numbers?
Stress-Strain Properties - 7
Lights Out 14 - 5x5, four stages, x moves
Pattern Recognition 2 - Known Unit Length, Various Array Length (including cell arrays)
Rule of mixtures (composites) - lower bound
Divisible by n, prime divisors - 11, 13, 17, & 19
Find the treasures in MATLAB Central and discover how the community can help you!
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