浮点数的比较

//功能：循环一直提醒用户继续输入，除非用户输入的值与正确值之间相差0.0001；
//伪代码：用到fabs()引用math.h  const 定义一个值  交互
#include<stdio.h>
#include<math.h>
#include<stdlib.h>
int main()
{
	const float answer = 3.14159;
	float response;
	printf("what is the value of pi?\n");
		scanf("%f", &response);
	while (fabs(response - answer) > 0.0001)
	{
		printf("try it again!\n");
			scanf("%f", &response);
	}
	printf("close enough!\n");
	system("pause");
	return 0;
}