要求质数很简单，但如何快速的求出质数则一直是程式设计人员与数学家努力的课题，在这边介绍一个着名的 Eratosthenes求质数方法。-Requirements primes is very simple, but how fast it has been determined primes programmers and mathematicians efforts topics here introduce a famous Eratosthenes seeking prime method