#include <iostream>
#include <iomanip>
#include <cmath>

using namespace std;

int main() {
    double r;
    const double PI = 3.14;
    cout << "\u8f93\u5165\u534a\u5f84: ";
    cin >> r;

    if (r < 0 || r > 100) {
        cout << "\u8f93\u5165\u9519\u8bef: \u534a\u5f84\u5fc5\u987b\u4e3a0\u5230100\u4e4b\u95f4" << endl;
        return 1;
    }

    double volume = (4.0 / 3) * PI * pow(r, 3);

    cout << fixed << setprecision(2);
    cout << "\u4f53\u79ef: " << volume << endl;

    return 0;
}