#include <stdio.h>
int main()
{
    double pi = 3.14159;
    double r; scanf("%lf", &r);
    if(r <= 0){
      printf("ERROR");
      return 0;
    }
    double x = 2.0 * r * pi;
    printf("%lf\n", x);
    printf("%lf", pi * r * r);
}