hdu 2199 Can you solve this equation?

本题链接：http://acm.hdu.edu.cn/showproblem.php?pid=2199

本题用二分法查找，AC代码：

#include<stdio.h>#include<math.h>double F(double x){double s=8*x*x*x*x+7*x*x*x+2*x*x+3*x+6;return s;}int main(){int T;scanf("%d",&T);while(T--){double m;scanf("%lf",&m);if( m > F(100) || m < F(0) ) printf("No solution!\n");else{double left,right,mid;left=0;right=100;while(right-left>1e-8){mid=(left+right)/2;if(m-F(mid)>1e-8)left=mid;else right=mid;}printf("%.4lf\n",mid);}}return 0;}