#include "stdio.h"
 #include "math.h"
 int main()
 {
     float a,b,c,disc,x1,x2,real,imag;
     scanf("%f%f%f",&a,&b,&c);
     if(fabs(a)<1e-6)  {printf("该方程不是二次方程！\n");return;}
     disc=b*b-4*a*c;
     if (fabs(disc)<=1e-6)
     printf("该方程有两个相等的实根: %.4f .\n",-b/(2*a));
     if (disc>1e-6)
     {x1=(-b+sqrt(disc))/(2*a);
      x2=(-b-sqrt(disc))/(2*a);
      printf("该方程有两个不相等的实根: %.4f , %.4f.\n",x1,x2);
     }
 if (disc<-1e-6)
 {real=-b/(2*a);
 imag=sqrt(-disc)/(2*a);
 printf("该方程有两个共轭复根:\n");
 printf("%.4f+%.4fi\n",real,imag);
 printf("%.4f-%.4fi\n",real,imag);
 }
 getchar();getchar();
 return (0);
 }