Question

C语言编程初学，求大佬指明错误！

#include <stdio.h>
#include <math.h>
int main()
{
double a,b,c,disc,x1,x2,realpart,imagpart;
scanf("%lf,%lf,%lf",&a,&b,&c);
printf("The equation ");
if(fabs(a)<=1e-6)
printf("is not a quadratic\n");//10
else
{
disc=b*b-4*a*c;
if(fabs(disc)<=1e-6)
printf("has two equal roots:");
printf("x1=x2=%8.4f",-b/(2*a));
else
if(disc>1e-6)
{
x1=(-b-sqrt(disc))/(2*a);//20
x2=(-b sqrt(disc))/(2*a);
printf("has two distinct roots:x1=%6.2lf x2=%6.2lf",x1,x2);
}
else
{
realpart=-b/(2*a);
imagpart=sqrt(-disc)/(2*a);
printf("has two complex roots:\n");
printf("x1=%8.4f-%8.4fi\n",realpart,imagpart);
printf("x2=%8.4f %8.4fi\n",realpart,imagpart);
}
}
rerurn 0;
}
（完了）
它说是18:error:identifier expected

Answer 1

#include <stdio.h>
#include <math.h>
int main()
{
    double a, b, c, disc, x1, x2, realpart, imagpart;
    scanf("%lf,%lf,%lf", &a, &b, &c);
    printf("The equation ");
    if (fabs(a) <= 1e-6)
        printf("is not a quadratic\n"); // 10
    else
    {
        disc = b * b - 4 * a * c;
        if (fabs(disc) <= 1e-6)
        {//<===============
            printf("has two equal roots:");
            printf("x1=x2=%8.4f", -b / (2 * a));
        }//<===============
        else if (disc > 1e-6)
        {
            x1 = (-b - sqrt(disc)) / (2 * a); // 20
            x2 = (-b + sqrt(disc)) / (2 * a);//<==============
            printf("has two distinct roots:x1=%6.2lf x2=%6.2lf", x1, x2);
        }
        else
        {
            realpart = -b / (2 * a);
            imagpart = sqrt(-disc) / (2 * a);
            printf("has two complex roots:\n");
            printf("x1=%8.4f-%8.4fi\n", realpart, imagpart);
            printf("x2=%8.4f %8.4fi\n", realpart, imagpart);
        }
    }
    return 0;//<============
}

追问

已采纳！感谢！我一直用的是手机版的C编辑器，Visual C 6.0和我的windows7不兼容。。如果你有兼容的软件的话麻烦发一下好嘛（或者告诉我个网址我自己下。。。）