#include <stdio.h>
#define Pi 3.14
int main(void)
{
double r,V;
scanf("%lf",&r);
V=4/3.0*Pi*r*r*r;
printf("%lf\n",V);
}

#include <stdio.h>
#define Pi 3.14
int main(void)
{
double r,V;
scanf("%lf",&r);
V=4/3.0*Pi*r*r*r;
printf("%lf\n",V);
}