include[HTML_REMOVED]

using namespace std;

int main()
{
double x;
scanf(“%lf”,&x);

double l=-10000,r=10000;
while(r-l>1e-8)
{
    double mid=(l+r)/2;
    if(mid*mid*mid>=x) r=mid;
    else l=mid;
}
printf("%.6lf",r);
return 0;

}