#include <bits/stdc++.h>
using namespace std;
template <typename T>
inline T abs(T a) {
  return a < 0 ? (-a) : a;
}
template <typename T>
inline T sqr(T x) {
  return x * x;
}
const double PI = 3.1415926535897932384626433832795;
int main() {
  double w, h, a;
  cin >> w >> h >> a;
  if (a > 90) a = 180 - a;
  if (h > w) swap(w, h);
  a = a / 180 * PI;
  double x = (w - h / tan((PI - a) / 2)) / 2;
  double y = (h - w / tan((PI - a) / 2)) / 2;
  if (y < 0) {
    printf("%.12f\n", h * h / sin(a));
  } else {
    printf("%.12f\n", w * h - tan(a) * (x * x + y * y));
  }
  return 0;
}
