输入几个数，告诉您有几个根

              
#include

int equation(double a,double b,double c)   
{
 if(b*b-4*a*c>0)
 {
  return 2;  
 }
 else if(b*b-4*a*c>0)
 {
  return 1;
 }
 else if(b*b-4*a*c<0)
 {
  return 0;
 }
}
int main()
{
 double a,b,c;
 scanf("%lf%lf%lf",&a,&b,&c);
 printf("%d\n",equation(a,b,c));
 return 0;
}