#include <bits/stdc++.h>
using namespace std;
int main() {
  double W, H, a;
  cin >> W >> H >> a;
  if (W < H) swap(W, H);
  double p = (W * W - H * H) / (2 * W);
  if (a > 90) a = 180 - a;
  a = (a / 180) * 3.14159265358979323846;
  if (tan(a) > H / p) {
    cout.precision(25);
    cout << (H * H) / sin(a) << endl;
    return 0;
  }
  double h = H * cos(a);
  double w = W * cos(a);
  double s = sin(a);
  double t = cos(a);
  double y = (h * (1 + t) - s * w) / (((1 + t) * (1 + t) - s * s) * t);
  double x = w / (1 + t) - (s * t) / (1 + t) * y;
  cout.precision(25);
  double res = W * H - x * x * tan(a) - y * y * s * t;
  cout << res << endl;
  return 0;
}
