3053. 택시 기하학

c
#include <bits/stdc++.h>

using namespace std;

int main(){
    cin.tie(NULL);
    cout.tie(NULL);
    ios_base::sync_with_stdio(false);

    double R;
    cin >> R;

    cout << fixed;
    cout.precision(6);
    cout << R * R * 3.14159265358979 << "\n";
    cout << R * R * 2 << "\n";

    return 0;
}```