题解 | #计算一元二次方程#

#include <stdio.h>
#include <math.h>


int main() {
    double a = 0;
    double b = 0;
    double c = 0;

    while (3 == scanf("%lf %lf %lf", &a, &b, &c))
    {
        if (a != 0)
        {
            double dif = b * b - 4 * a * c;
            
            if (0 == dif)
            {
                printf("x1=x2=%.2lf\n", ((-b / (2 * a) != 0) ? (-b / (2 * a)): 0));
            }
            else if (dif > 0)
            {
                printf("x1=%.2lf;x2=%.2lf\n", (-sqrt(dif) - b) / (2 * a), (sqrt(dif) - b) / (2 * a));
            }
            else
            {
                printf("x1=%.2lf-%.2lfi;x2=%.2lf+%.2lfi\n",(-b)/ (2 * a),sqrt(-dif) / (2 * a), (-b) / (2 * a), (sqrt(-dif) / (2 * a)));
            }
        }
        else
        {
            printf("Not quadratic equation\n");
        }
    }
    
    return 0;
}