Cody

Problem 1761. Primes Faster for Large N

Solution 299483

Submitted on 9 Aug 2013 by Jan Orwat
This solution is locked. To view this solution, you need to provide a solution of the same size or smaller.

Test Suite

Test Status Code Input and Output
1   Pass
feval(@assignin,'caller','score',30); %

2   Pass
%% tic assert(isequal(primes_faster(1),primes(1))) assert(isequal(primes_faster(2),primes(2))) for i=1:100 n=randi(2000,1); assert(isequal(primes_faster(n),primes(n))) end toc

Elapsed time is 0.037774 seconds.

3   Pass
%% tic ta=clock; p = primes_faster(2^28); t1=etime(clock,ta); % time in sec fprintf('P 2^28 %12i %10.3f\n',length(p),t1) assert(isequal(size(unique(p),2),14630843)) ptr=randi(7603553,1,10); % small to avoid timeout pchk=double(p(ptr)); assert(all(isprime(pchk))) feval( @assignin,'caller','score',floor(min(30,t1)) ); toc

P 2^28 14630843 10.695 Elapsed time is 12.382377 seconds.

Suggested Problems

More from this Author246

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!