题解 | 计算一元二次方程

#include <stdbool.h>
#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 derta,x1,x2;
         derta=b*b-4*a*c;
        if (derta==0) {
            x1=-b/(2*a);
            if (x1==-0.0) {
                x1=0;
            }
             printf("x1=x2=%0.2f\n",x1);
        }
        else if(derta>0){
            x1=(-b+sqrt(derta))/(2.0*a);
            x2=(-b-sqrt(derta))/(2.0*a);
            if(x1<=x2){
               printf("x1=%0.2f;x2=%0.2f\n",x1,x2);
            }
            else{
                float tmp=x1;
                x1=x2;
                x2=tmp;
                printf("x1=%0.2f;x2=%0.2f\n",x1,x2);
            }
        }
        else{
            float realPart = -b / (2 * a);
            float imagPart = sqrt(-derta) / (2 * a);
            // 处理-0.00的情况
            if (realPart == -0.0f) realPart = 0.0f;
            if (imagPart == -0.0f) imagPart = 0.0f;
            
            if (realPart != 0.0f) {
                printf("x1=%.2f-%.2fi;x2=%.2f+%.2fi\n", realPart, imagPart, realPart, imagPart);
            } else {
                printf("x1=%.2fi;x2=%.2fi\n", -imagPart, imagPart);
            }
        }
    }
    }
    
    return 0;
}