Prime Number Algorithm

Question

Can anyone tell me how to implement Sieve of Eratosthenes algorithm in C? I need to generate prime numbers but my algorithm is slow.

My code:

#inclu         


        

Answer 1

Though it's very old post, Following is my try to generate the prime number using "Sieve of Eratosthenes" algorithm.

#include 

#define NUM 8000        /* Prime Numbers in the Range.  'Range + 2' actually. */

int main()
{
  int a[NUM] = {0};         /* Array which is going to hold all the numbers */
  int i , j;

  /* initializing array from 2 to given number + 2, assuming the first prime number is 2 */
  for(i = 2,j=0; i < NUM+2, j

Hope this will help someone.