Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.
Ask questions, find answers and collaborate at work with Stack Overflow for Teams.
Ask questions, find answers and collaborate at work with Stack Overflow for Teams. Explore Teams
Teams
Q&A for work
Connect and share knowledge within a single location that is structured and easy to search.
n=1000000;t=true;a=[t]*n;n=999984;t=true;a=[t]*n;(2..Math.sqrt(n).round).each{|i|a[i]&&(i..n/i).each{|j|a[j*i]=!t}};(2..n).each{|i|a[i]&&p(i)}
0.54s53s user 0.13s system 89%92% cpu 0.752714 total
n=1000000;t=true;a=[t]*n;(2..Math.sqrt(n).round).each{|i|a[i]&&(i..n/i).each{|j|a[j*i]=!t}};(2..n).each{|i|a[i]&&p(i)}
0.54s user 0.13s system 89% cpu 0.752 total
n=999984;t=true;a=[t]*n;(2..Math.sqrt(n).round).each{|i|a[i]&&(i..n/i).each{|j|a[j*i]=!t}};(2..n).each{|i|a[i]&&p(i)}
0.53s user 0.13s system 92% cpu 0.714 total
