弱校联盟 10.7

#include <cmath>
#include <cstdio>
using namespace std;
const double eps = 1e-8;
#define PI acos(-1.0)
double S;
double GetH(double r){
    double a = S/PI/r - r;
    a = a*a - r*r;
    return sqrt(a);
}
double GetV(double r, double h){
    return PI*r*r*h/3;
}
int main(){
    while(scanf("%lf", &S) != EOF){
        double l, r, lm, rm, lV, rV;
        l = 0.00001;
        r = sqrt(S/PI/2);
        while(r-l > eps){
            lm = (r-l)/3 + l;
            rm = (r-l)/3*2 + l;
            lV = GetV(lm, GetH(lm));
            rV = GetV(rm, GetH(rm));
            if(lV < rV) l = lm;
            else r = rm;
        }

        double h = GetH(r);
        double V = GetV(r, h);
        printf("%.2lf\n%.2lf\n%.2lf\n", V, h, r);
    }
    return 0;
}