OJ-Problems-Source/HDOJ/2899_autoAC.cpp

47 lines
862 B
C++

#include<cstdio>
#include<cstring>
#include<iostream>
#include<utility>
#include<string>
#include<vector>
#include<algorithm>
#include<queue>
#include<cstdlib>
#include<cmath>
using namespace std;
const double eps=1e-8;
int y;
double g(double x)
{
return 42*pow(x,6)+48*pow(x,5)+21*pow(x,2)+10*x;
}
double f(double x)
{
return 6*pow(x,7)+8*pow(x,6)+7*pow(x,3)+5*pow(x,2)-y*x;
}
int main()
{
int T;
scanf("%d",&T);
while(T--)
{
scanf("%d",&y);
if(g(100.0)-y<=0)
{
printf("%.4lf\n",f(100.0));
continue;
}
double l=0,r=100,m;
while(l+eps<=r)
{
m=(l+r)/2;
if(g(m)-y<0)
l=m;
else
r=m;
}
printf("%.4lf\n",f(m));
}
return 0;
}