P4326 [COCI2006-2007#1] Herman

题目链接

#include<stdio.h>
#include<math.h>
const double pi = acos(-1.0);
int main()
{double R;scanf("%lf", &R);printf("%.6lf\n%.6lf\n", pi * R * R, 2 * R * R);return 0;
}