C语言给定一个数N列出所有不大于N的素数

#include <stdio.h>
#include <stdlib.h>

#define COUNTS 4294967295

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Author：Stat&陈

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int get_prime_number(unsigned long);

int main(void)
{
   unsigned long number, i, count;

   printf("Please enter a number:\n");
   scanf("%lu", &number);

   if(1 > number && COUNTS < number){
      fprintf(stderr, "Out of range!\n");
      exit(1);
   }

   for(i = 2, count = 0; i < number; i++)
      count += get_prime_number(i);

   printf("\nprime number: %lu\n", count);
   return 0;
}

int get_prime_number(unsigned long a)