题解 | #计算一元二次方程#

#include<stdio.h>
#include<math.h>
int main()
{
    float a,b,c;
    while(scanf("%f %f %f",&a,&b,&c)!= EOF)
    {
      
        if(a==0) printf("Not quadratic equation\n");
        else
        {
            float d=b*b-4*a*c;
            if(d==0)
            {
                printf("x1=x2=%.2f\n",(-b+sqrt(d))/(2*a));
            }else if(d>0)
            {
               printf("x1=%.2f;x2=%.2f\n",(-b-sqrt(d))/(2*a),(-b+sqrt(d))/(2*a));
            }else 
            {
                float x = (-b)/(2*a),y = sqrt(-d)/(2*a);
                if(x==-0) x=-x;
                printf("x1=%.2f-%.2fi;x2=%.2f+%.2fi\n",x,y,x,y);
            }
        }
    }
    return 0;
}