题解 | #计算一元二次方程#

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

int main() {
    float a = 0;
    float b = 0;
    float c = 0;
    float d = 0;
    float x1 = 0;
    float x2 = 0;
    float s = 0;
    float x = 0;

    while(scanf("%f %f %f", &a, &b, &c)!=EOF){
    d = b * b - 4 * a * c;
    if (a == 0) {
        printf("Not quadratic equation");
    }else if(d==0){
        if(a<0){
            a=-a;
        }
        x1 = (-b+sqrt(d)) / (2 * a);
        printf("x1=x2=%.2f",x1);
        printf("\n");
    }else if(d>0){
        x1 = (-b - sqrt(d)) / (2 * a);
        x2 = (-b + sqrt(d)) / (2 * a);
        printf("x1=%.2f;x2=%.2f", x1, x2);
        printf("\n");
    }
    else {
        s = -b / (2 * a);
        x = sqrt(-d) / (2 * a);
        printf("x1=%.2f-%.2lfi;x2=%.2f+%.2fi", s, x, s, x);
        printf("\n");
    }
    }
}