#include <iostream>
#include <cmath>

using namespace std;

int main() {
    double sudut, kecepatan;
    const double g = 10;

    cin >> sudut >> kecepatan;

    double sudut_rad = sudut * M_PI / 180.0;
    double jarak = (pow(kecepatan, 2) * sin(2 * sudut_rad)) / g;

    cout << fixed;
    cout.precision(1);
    cout << jarak << endl;

    return 0;
}