matcoder's blog

By matcoder, history, 6 years ago, In English

Segmented sieve of Eratosthenes can be used to evaluate prime numbers less than n, where n is large enough in pretty less time and memory.

Time complexity: O(n.log(log(n)))

Space complexity: O(sqrt(n))

Link:

https://primesieve.org/segmented_sieve.html

  • Vote: I like it
  • +13
  • Vote: I do not like it

| Write comment?
»
6 years ago, # |
  Vote: I like it +7 Vote: I do not like it

Auto comment: topic has been updated by matcoder (previous revision, new revision, compare).

»
6 years ago, # |
  Vote: I like it +5 Vote: I do not like it

If you had posted this 1 day earlier, I could've solved problem C at the NCTU camp :(. (the problem involved looking for minimum prime gaps in a given range, where the left and right bounds can be very big, but their difference is small).

Be it late or not, at least I learned something :).

»
3 years ago, # |
  Vote: I like it -9 Vote: I do not like it

If n is 1e9, then T.C. would be O( 1e9 * log( log( 1e9) ) ) ?