生成具有上限的素数 [英] Generate prime numbers with upper limit

问题描述

我正在尝试生成一个上限内的素数列表，例如。 100：所以它应该从0生成100以下的所有素数。

我遵循Sieve of Eratosthenes算法，但不能在代码中实现它。多次尝试。

我要做的是：

I am trying to generate a list of prime numbers within a upper limit , eg. 100: so it should generate all the prime numbers below 100 from 0.
I was following Sieve of Eratosthenes algorithm , but cant implement it in code. Tried many times.
What i am trying to do is:

引用：

假设所有数字的列表从2到N.

设p最初等于2.第一个素数。

从列表中删除小于或等于N的所有倍数。

找到p后面的下一个数字，该数字尚未在列表中划掉。这是下一个素数。

对新p重复步骤3和4，除非p2大于N.

列表中没有划掉的数字是下面的素数limit N。

Assume list of all numbers from 2 to N.
Let p initially equal to 2. The first prime.
Strike all multiples of p from the list less than or equal to N.
Find the next number after p, that’s not yet crossed out on the list. This is the next prime.
Repeat step 3 and 4 for the new p, unless p2 is greater than N.
Numbers not crossed out on the list are primes below the limit N.

我可以不使用数组做到这一点，或者我必须使用数组肯定。

还有任何其他方法来生成Prime数字（即使检测它们，我会在以后自己工作）。谢谢

Can i do this without using an array, or do i have to use an array for sure.
Also is there any other method to generate Prime numbers( even to detect them , i would work on later myself). Thanks

推荐答案

算法：

Algorithm:

引用：

创建从2到N的所有数字的列表。

[...]

Create list of all numbers from 2 to N.
[...]

问题：

Question:

引用：

我可以在不使用数组的情况下执行此操作，还是必须使用数组。

Can i do this without using an array, or do i have to use an array for sure.

答案： 不，你不能。



[update]

当然，使用阵列可以找到0到100之间的素数。对于每个候选人 n 只测试 2 和 n （整数）平方根，除以它

[/ update]

Answer: "No, you cannot".

[update]
Finding the prime numbers between 0 and 100 wihtout using an array is possible, of course. For each candidate n just test if there is a number between 2 and n (integer) square root, dividing it
[/update]

我们不要在这里做作业。你说你已经尝试了很多次，但是没有在这里发布你的代码，以便我们帮助解决一个特定的问题。



说了这个链接以获得一些建议



http://stackoverflow.com/questions/14211628/listing-prime-numbers-up-to-2-billion-using-sieves-method-in-c [ ^ ]



Google提供的这些结果还有很多其他建议。我已将完整链接保留在视图中，以便您可以查看搜索条件是什么



https://www.google.co.uk/#q=sieve+of+eratosthenes+prime+数字+上涨+至+ 100 + C& safe =有效 [ ^ ]

We don't do homework here. You say you have tried many times but have not posted your code here for us to help with a specific problem.

Having said that look at this link for some suggestions

http://stackoverflow.com/questions/14211628/listing-prime-numbers-up-to-2-billion-using-sieves-method-in-c[^]

And there are many many more suggestions with these results from google. I've left the full link in view so you can see what the search criteria were

https://www.google.co.uk/#q=sieve+of+eratosthenes+prime+numbers+up+to+100+C&safe=active[^]

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