hdu 2899

#include<stdio.h>
#include<string.h>
#include<stdlib.h>
#include<math.h>
#include<algorithm>
#define N 1010
#define INF 0x3f3f3f3f

using namespace std;

int main()
{
    int t;
    double y, f, f1;
    scanf("%d", &t);
    while(t--)
    {
        scanf("%lf", &y);
        double mid, low = 0, high = 100;
        while(high - low > 1e-8)/***此处注意*/
        {
            mid = (low + high) / 2;
            f1 = 42 * pow(mid, 6) + 48 * pow(mid, 5) + 21 * pow(mid, 2) + 10 * mid;//导数
            if(f1 < y)
                low = mid;
            else if(f1 == y)
                break;
            else
                high = mid;
        }
        f = 6 * pow(mid, 7) + 8 * pow(mid, 6) + 7 * pow(mid, 3) + 5 * pow(mid, 2) - mid * y;
        printf("%.4f\n", f);
    }
    return  0;
}