hdu 2199 java 二分法

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

Sample Output
1.6152
No solution!

import java.util.Scanner;


public class P2199 {
    public static void main(String[] args) {
        Scanner sc=new Scanner(System.in);
        int t=sc.nextInt();
        while(t-->0){
            long y=sc.nextLong();
            double left=0;
            double right=100;
            if(y-f(left)<0||y-f(right)>0){
                System.out.println("No solution!");
                continue;
            }else{
                while(right-left>Math.pow(10, -6)){
                    double mid=(right+left)/2;
                    if(f(mid)>y){
                        right=mid;
                    }else {
                        left=mid;
                    }
                }
                System.out.printf("%.4f",right);
                System.out.println();
            }
        }
    }

    public static double f(double x){
        return 8*myPow(x,4) + 7*myPow(x,3) + 2*myPow(x,2) + 3*x + 6;
    }
    public static double myPow(double x,int i){
        return Math.pow(x, i);
    }
}