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

Here is actually very simple code that use the Sieve of Eratosthenes algorithm. works for all positive int.

int is_prime(int n){
  int p;
  for(p = 2; p < n; p++){
    if(n % p ==0 && p != n)
      return 0;    
  }
  return 1;
}