C语言编程题代码为什么不对

样例输入为: 1 5 -2 <<<样例应该是空白符为分隔
程序写成了输入逗号分隔: scanf("%f,%f,%f",&a,&b,&c);

改正为: scanf("%f%f%f",&a,&b,&c);修改之后就正确了，调试通过

# include
# include

int main(void)
{
double a, b, c;
double delta;
double x1, x2;
char ch;

do
{
printf("请输入一元二次方程的三个系数:\n");
printf("a = ");
scanf("%lf", &a);

printf("b = ");
scanf("%lf", &b);

printf("c = ");
scanf("%lf", &c);

delta = b*b - 4*a*c;

if (delta > 0)
{
x1 = (-b + sqrt(delta)) / (2*a);
x2 = (-b - sqrt(delta)) / (2*a);
printf("有两个解，x1 = %lf, x2 = %lf\n", x1, x2);
}
else if (0 == delta)
{
x1 = x2 = (-b) / (2*a);
printf("有唯一解，x1 = x2 = %lf\n", x1, x2);
}
else
{
printf("无实数解!\n");
}

printf("您想继续么(Y/N): ");
scanf(" %c", &ch); //%c前面必须得加一个空格
}
while ('y'==ch || 'Y'==ch);

return 0;
}
//可以参考一下

样例输入: 1 5 -2 <<<样例是空白符为分隔
程序写成了输入逗号分隔: scanf("%f,%f,%f",&a,&b,&c);

改正为: scanf("%f%f%f",&a,&b,&c);