#include <bits/stdc++.h>
using namespace std;
int main() {
  double w, h, a;
  cin >> w >> h >> a;
  if (w < h) {
    double t = h;
    h = w;
    w = t;
  }
  if (a > 90) a = 180 - a;
  double alpha = a * 3.14159265 / 180.0;
  if (alpha >= 2 * atan(h * 1.0 / w)) {
    cout << setprecision(20) << h * h * 1.0 / (sin(alpha)) << endl;
  } else {
    double x = (w - h * tan(alpha / 2)) / 2.0;
    double y = (h - w * tan(alpha / 2)) / 2.0;
    cout << setprecision(20) << w * h - x * x * tan(alpha) - y * y * tan(alpha)
         << endl;
  }
  return 0;
}
