题解 | #计算一元二次方程#

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

int main() 
{
    double a, b, c;
    double x = 0,derta = 0;
    while (scanf("%lf %lf %lf ", &a, &b, &c) != EOF) 
    {
        derta = b*b - 4*a*c;
        if(a == 0)
        {
            printf("Not quadratic equation\n");
        }
        else 
        {
            if(derta == 0)
            {
                if(-b/(2.0*a) == 0)
                 printf("x1=x2=0.00\n");
                else
                 printf("x1=x2=%.2lf\n",-b/(2.0*a));
            }
            else if(derta > 0)
            {
                printf("x1=%.2lf;x2=%.2lf\n",(-b-sqrt(derta))/(2.0*a),(-b+sqrt(derta))/(2.0*a));
            }
            else 
            {
                printf("x1=%.2lf%.2lfi;x2=%.2lf+%.2lfi\n",-b/(2.0*a),-sqrt(-derta)/(2.0*a),-b/(2.0*a),sqrt(-derta)/(2.0*a));
            }
        }
    }
    return 0;
}