include

include

using namespace std;

double cubeRoot(double x){
int flag=1;
if(x<0){
x=-x;
flag=-1;
}
double L;
double R;
double m;
double ERR;
if(x>1){
ERR=0.01;
L=0;
R=x;
while(1){
m=L+(R-L)/2.0;
if(mmm-x<=ERR && x-mmm<=ERR)
return mflag;
else if(mmm-x>ERR)
R=m;
else
L=m;
}
}
else{//0-1
ERR=0.00001;
L=x;
R=1;
while(1){
m=L+(R-L)/2.0;
if(mmm-x<=ERR && x-mmm<=ERR)
return mflag;
else if(mmm-x>ERR)
R=m;
else
L=m;
}
}
}

int main(){
double d;
cin>>d;
d=cubeRoot(d);
printf("%0.1f",d);
return 0;
}