pta怎么也不过？拜托各位大佬帮我指正一下

#include<stdio.h>
#include<math.h>

int main(void)
{
	int i,flat;
	double item,sum,eps;
	flat = 1;
	sum = 0;
	i = 1;
	item = 1.0;
	printf("Enter a number:");
	scanf("%lf", &eps);
	do{
        item = flat *1.0 / i;
		sum = sum + item;
		flat = -flat;
		i = i + 3;
		
     }while(fabs(item)>eps);
	printf("sum = %.6f\n", sum);

	return 0;
}

`printf("Enter a number:");`这样的语句通常需要注释或删除掉。

另外题主没说是pta哪题？