//求ax2+bx+c=0方程的解
#include<stdio.h>
#include<math.h>
void main()
{
    float a,b,c,disc,x1,x2,realpart,imagpart;
    printf("请输入a,b,c的值：\n");
    scanf("%f,%f,%f",&a,&b,&c);
    printf("The equation ");
    if(fabs(a)<=1e-6)   //相当于=0
        printf("is not a quadratic\n");
    else
    {
        disc=b*b-4*a*c;
        if(fabs(disc)<=1e-6)   //相当于=0
            printf("has two equal roots:%8.4fand %8.4f\n",-b/(2*a));
        else
            if(disc>1e-6)
            {
                x1=(-b+sqrt(disc))/(2*a);
                x2=(-b-sqrt(disc))/(2*a);
                printf("has distinct real roots:%8.4f and %8.4f\n",x1,x2);
            }
            else
            {
                realpart=-b/(2*a);
                imagpart=sqrt(disc)/(2*a);
                printf("此方程有2个复解：\n");
                printf("%8.4f+%8.4fi\n",realpart,imagpart);
                printf("%8.4f-%8.4fi\n",realpart,imagpart);
            }
    }
}

D:\vc\vc\MSDev98\MyProjects\t1\t1.1.c(20) : warning C4244: '=' : conversion from 'double ' to 'float ', possible loss of data
D:\vc\vc\MSDev98\MyProjects\t1\t1.1.c(21) : warning C4244: '=' : conversion from 'double ' to 'float ', possible loss of data
D:\vc\vc\MSDev98\MyProjects\t1\t1.1.c(27) : warning C4244: '=' : conversion from 'double ' to 'float ', possible loss of data
运行每次都有这几个警告，运行结果也不对，我找 了好多资料就是不知道错在哪啊，求助！！！感激不尽！

调试了一下，大概是这样吧

//求ax2+bx+c=0方程的解
#include<stdio.h>
#include<math.h>
int main()
{
    double a,b,c,disc,x1,x2,realpart,imagpart;
    printf("请输入a,b,c的值：\n");
    scanf("%lf,%lf,%lf",&a,&b,&c);
    printf("The equation ");
    if(fabs(a)<=1e-6)   //相当于=0
        printf("is not a quadratic\n");
    else
    {
        disc=b*b-4*a*c;
        if(fabs(disc)<=1e-6)   //相当于=0
            printf("has two equal roots:%8.4f and %8.4f\n",-b/(2*a),-b/(2*a));
        else
            if(disc>1e-6)
            {
                x1=(-b+sqrt(disc))/(2*a);
                x2=(-b-sqrt(disc))/(2*a);
                printf("has distinct real roots:%8.4f and %8.4f\n",x1,x2);
            }
            else
            {
                realpart=-b/(2*a);
                imagpart=sqrt(-1*disc)/(2*a); //这里disc为负，所以要乘以-1才能开平方
                printf("此方程有2个复解：\n");
                printf("%8.4f+%8.4fi\n",realpart,imagpart);
                printf("%8.4f-%8.4fi\n",realpart,imagpart);
            }
    }
    return 0;
}

 

谢谢，我运行了一下  警告没有了，但是结果还是不对，为什么会这样呢？

我的 gcc调试通过


[ 本帖最后由 lonmaor 于 2012-3-13 09:41 编辑 ]

我想哭了 我用的VC6.0，怎么会这样啊，谢谢你啊，非常感谢