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

int main() {
    double v0, sudut;
    std::cin >> v0 >> sudut;
    double jarak = (v0*v0 * sin(2 * sudut * 3.14159265 / 180.0)) / 10.0;
    std::cout << std::fixed << std::setprecision(1) << jarak << std::endl;
    return 0;
}