C++ :

#include <iostream>
#include <iomanip>
using namespace std;
int main() {
    double r, pi = 3.14159;
    cin >> r;
    double d = r * 2;
    double c = 2 * pi * r;
    double s = pi * r * r;
    printf("%.4lf %.4lf %.4lf", d, c, s);

    return 0;
}