#include<stdio.h>   //请帮我看看，这程序哪里有问题。。才导致下面的运行结果。这是求ax^2+bx+c=0的根的程序

#include<math.h>
    void fun1(double a,double b,double c,double d)      //Δ=0的情况
    {
        double ans=-b/(2*a);
        printf("b^2-4*a*c==0,x1=x2=%lf.\n",ans);
        }
 void fun2(double a,double b,double c,double d)  //Δ>0的情况
 {
     double ans1,ans2;
     ans1=(-b-sqrt(d))/(2*a);
     ans2=(-b-sqrt(d))/(2*a);
     printf("b^2-4*a*c>0,x1=%lf,x2=%lf.\n",ans1,ans2);
 }，
 void fun3(double a,double b,double c,double d)  //Δ<0的情况，输出复数解
 {
     double real,imar;
     real=-b/(2*a);
     imar=sqrt(-d)/(2*a);
     printf("b*b-4*a*c<0,x1=%lf+%lfi,x2=%lf-%lfi.\n",real,imar,real,imar);
 }
 int main(）      //我感觉是不是主函数的问题
 {
     void fun1(double a,double b,double c,double d);
     void fun2(double a,double b,double c,double d);
     void fun3(double a,double b,double c,double d);
     double a,b,c,d;
     printf("please intput a,b,c.\n");
     while(scanf("%lf，%lf，%lf",&a,&b,&c)!=EOF)      
        {
         d=b*b-4*a*c;
         if(d==0)fun1(a,b,c,d);
         else if(d>0)fun2(a,b,c,d);
         else fun3(a,b,c,d);
         printf("please enter put a,b,,c.\n");
     }
}

           //无限循环，用的DEV编译器

[此贴子已经被作者于2016-5-25 16:24编辑过]

能运行啊，我都发图了。

确实好了。但是我希望可以循环输入的。用while语句怎么不行？