Can you solve this equation?

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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

2100-4

Sample Output

1.6152No solution!

YYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYY
因为f函数是单调递增的，所以可以用二分；

#include<stdio.h>#include<math.h>double f(double x){return (8*x*x*x*x + 7*x*x*x + 2*x*x + 3*x + 6);}int main(){int ncase,i,j,k;double m,n;scanf("%d",&ncase);while(ncase--){scanf("%lf",&m);if(f(0)>m||f(100)<m){printf("No solution!\n");continue;}double l,r;l=0.0;r=100.0;double mid=50.0;while(fabs(f(mid)-m)>1e-5){     if((f(mid)>m)) { r=mid; mid=(l+r)/2;  }  else if(f(mid)<m)  {  l=mid;  mid=(l+r)/2;    }}printf("%.4lf\n",mid);}return 0;}