请问Else是哪里没有配对起来

牛课网的各位大牛好，我刚刚学习C语言，有很多不懂的问题，请问知道，谢谢

请问以下程序第16行else为什么显示没有配对起来，非常感谢，在线等，小妹感谢

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