#include <iostream>
#include <cmath>
#define eps 0.00001
using namespace std;
double f(double x){
    return x*x*x-3;
}

double Root(double a, double b, double (*f)(double)){
    double x=(a+b)/2;
    if (fabs(f(x))<eps)
        return x;
    else{
        if (f(x)*f(a)<0)
            return Root(a,x,f);
        else
            return Root(x,b,f);
    }
}

int main(int argc, char *argv[])
{
    double x = Root(0, 2, f);
    cout << x << endl;
    return 0;
}