用c语言验证哥德巴赫猜想

#include 

int Is_Primer(int num)
{
    int i;
    int pow_num;

    pow_num = sqrt(num);
    for(i = 2; i <= pow_num; i++)
    {
        if(0 == (num % i))
	{
	    return -1;
	}
    }
    return 0;
}

void Goldbach_Guess(int max_num)
{
    int even;
    int i;

    printf("Goldbach is right:\n");
    for(even = 2; even <= max_num; even += 2)
    {
        for(i = 1; i < even; i++)
	{
	    if(0 == Is_Primer(i))
	    {
	        if(0 == Is_Primer(even - i))
		{
		    printf("%d + %d = %d\n", i, even - i, even);
		    break;
		}
	    }
	}
    }
}

int main()
{
    int max_num;

    printf("Please input the max_num:\n");
    scanf("%d", &max_num);

    Goldbach_Guess(max_num);

    return 0;
}