How to optimize Ruby code?

[ducnguyen_sof]

I have tried PRIME1 with ruby and finally got accepted after so many TLEs . But it is still too low. I think the most of time was spent to print out the data. Other version in java and c run only under 1 sec!

So can I make it a little faster? What can be optimized?
I see the best submit run in only 3 or 4 sec (ruby). How you guys do it???

[ricardohead]

Can you please tell me, how did you managed the input and output data in ruby?, My PRIME1 problem works fine in my computer but when I submit to the judge gives me a Runtime Error (NZEC) I think something is wrong when manage the input data because the algorithm works fine.

Thanks a lot.