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): 1182 Accepted Submission(s): 558

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!

 

Author

Redow

 

Recommend

lcy

#include<bits/stdc++.h>
#define op 1e-8
using namespace std;
double F(double x)
{
    return 8*x*x*x*x+7*x*x*x+2*x*x+3*x+6;
}
int main()
{
    //freopen("C:\Users\acer\Desktop\in.txt","r",stdin);
    int t;
    double n;
    scanf("%d",&t);
    while(t--)
    {
        scanf("%lf",&n);
        if(n<6||n>807020306)
        {
            puts("No solution!");
            continue;
        }    
        double l=0,r=100,mid;
        while(fabs(r-l)>op)
        {
            mid=(l+r)*1.0/2;
            if(F(mid)>n)
                r=mid;
            else
                l=mid;
        }
        printf("%.4lf
",l);
    }
    return 0;
}