#include
#include
double f(double x)
{double y;
y=((x-5.0)*x+16.0)*x-80.0;
return(y);
}
double xpoint(double x1,double x2)
{
double y;
y=(x1+x2)/2;
return(y);
}
double root(double x1,double x2)
{
double x,y,y1;
y1=f(x1);
do
{
x=xpoint(x1,x2);
y=f(x);
if(y*y1>0)
{
y1=y;
x1=x;
}
else
x2=x;
}
while (fabs(y)>=0.0001);
return(x);
}
void main()
{
double x1,x2,f1,f2,x;
do
{
printf("input x1,x2\n");
scanf("%f %f",&x1,&x2);
f1=f(x1);
f2=f(x2);
}
while (f1*f2>=0);
x=root(x1,x2);
printf("A root of equation is%8.4f\n",x);
}
这程序我在Visual C++6.0下运行，输入2 6，为啥结果还是输出input x1,x2。希望有高手给予解惑啊！
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