C语言一元二次方程

C语言一元二次方程的写法

# include <stdio.h>
# include <math.h>
int main (void){
//  把三个系数保存到变量当中
    int a = 1;
    int b = 2;
    int c = 3; 
    
//  定义一个变量来判断到底有几个解
    double solution;
    solution = b*b - 4*a*c; 
//  定义两个变量来装解 
    double x1;
    double x2;
    
//  通过判断 solution的值来判断有几个解
    if(solution > 0)
    {
        x1 = (-b + sqrt(solution)) / (2*a);
        x2 = (-b - sqrt(solution)) / (2*a);
        printf("该方程有两个解，x1 = %f x2 = %f\n" ,x1,x2);
    } else if(solution == 0)
    {
        x1 = (-b + sqrt(solution)) / 2*a;
        x2 = x1;
        printf("该方程有一个解，x1 = x2 = %f\n" ,x1);
    }else if(solution < 0)
    {
        printf("该方程无解\n");
    }
    return 0;
}