题解 | #计算一元二次方程#

#include <stdio.h>
#include <math.h>
int main() {
    float a, b,c;
    float x1,x2;
    while((scanf("%f%f%f",&a,&b,&c))!=EOF){
        if(a==0){
            printf("Not quadratic equation\n");
        }
        else{
            float delta=b*b-4*a*c;
            if(delta==0){
                x1=x2=-b/(2*a);
                if(fabs(x1)<0.000001){
                    x1=0.00;
                }
                printf("x1=x2=%.2f\n",x1);
            }
            else if(delta>0){
                x1=(-b-sqrt(delta))/(2*a);
                x2=(-b+sqrt(delta))/(2*a);
                printf("x1=%.2f;x2=%.2f\n",x1,x2);
            }
            else{
                float real_part=-b/(2*a);
                float imaginary_part=sqrt(-delta)/(2*a);
                printf("x1=%.2f-%.2fi;x2=%.2f+%.2fi\n",real_part,imaginary_part,real_part,imaginary_part);
            }
        }
    }
    return 0;
}