hdu2199 Can you solve this equation?

Can you solve this equation?

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 13731    Accepted Submission(s): 6115

Problem Description

Now,given the equation 8*x^4 + 7*x^3 + 2*x^2 + 3*x + 6 == Y,can you find its solution between 0 and 100;
Now please try your lucky.

 

Input

The first line of the input contains an integer T(1<=T<=100) which means the number of test cases. Then T lines follow, each line has a real number Y (fabs(Y) <= 1e10);

 

Output

For each test case, you should just output one real number(accurate up to 4 decimal places),which is the solution of the equation,or “No solution!”,if there is no solution for the equation between 0 and 100.

 

Sample Input

   
   
   
   

    
    
    
    2
100
-4
   
   
   
   

 

#include<iostream>
#include<stdio.h>
#include<math.h>
using namespace std;
double fan(double x){
	return 8*pow(x,4)+7*pow(x,3)+2*pow(x,2)+3*x+6;
}
double Binsearch(double l,double h,double k){
	double mid;
	while(h-l>1e-10)   //精度
	{
		mid=(h+l)/2;
		if(fan(mid)>k) h=mid;
		else l=mid;
	}
	return mid;
}
int main()
{
    int T;
    double s;
    cin>>T;
    while(T--)
    {
        cin>>s;
        if(fan(1)>s||fan(100)<s)
	cout<<"No solution!\n";
	else printf("%.4lf\n",Binsearch(0,100,s));
    }
    return 0;
}