题解 | #计算一元二次方程#

#include <stdio.h>
#include <math.h>
int main()
{
    float a = 0.0;
    float b = 0.0;
    float c = 0.0;
    while (scanf("%f %f %f", &a, &b, &c) != EOF)
    {
        if (a == 0)
        {
            printf("Not quadratic equation\n");
        }
        else
        {
            float t=b*b-4*a*c;
                if(t==0){
                    float mp=-b+sqrt(t);
                    if(mp==0){
                    printf("x1=x2=%.2f",mp);
                }
                else {
                printf("x1=x2=%.2f\n",(-b+sqrt(t))/2.0/a);
                }
        }else if(t>0){
                printf("x1=%.2f;x2=%.2f\n",(-b-sqrt(t))/2.0/a,(-b+sqrt(t))/2.0/a);
        }else {
                printf("x1=%.2f-%.2fi;x2=%.2f+%.2fi\n",-b/2/a,sqrt(-t)/2/a,-b/2/a,sqrt(-t)/2/a);
            }
    }
}
}