二分法求一元二次方程的根

//二分法求方程的根
#include
#include
double EPS=1e-6;
double f(double x){ return  x*x*x-5*x*x+10*x-80; }
int main(){


	double root,x1=0,x2=100,y;
	root=x1+(x2-x1)/2;
	int triedTimes =1;
	y=f(root);
	while(fabs(y)>EPS){
		if(y>0) x2=root;
		else    x1=root;
		root=x1+(x2-x1)/2;
		y=f(root);
		triedTimes ++;
	}
	printf("%.8f\n",root);
	printf("%d",triedTimes);
	return 0;
}