#include <bits/stdc++.h>
using namespace std;
const double EPS = 1E-7;
inline int SG(double x) {
  if (x > -EPS && x < EPS) return 0;
  return x > 0 ? 1 : -1;
}
int main() {
  double w, h, a, b, d, h1, h2;
  const double pi = acos(-1.0);
  scanf("%lf %lf %lf", &w, &h, &a);
  if (w < h) swap(w, h);
  if (SG(a - 90) == 0) {
    printf("%.12f\n", h * h);
  } else if (SG(a - 180) == 0 || SG(a) == 0) {
    printf("%.12f\n", w * h);
  } else {
    if (SG(a - 90) > 0) {
      a = 180 - a;
    }
    a = a / 180.0 * pi;
    b = atan(h / w);
    d = sqrt(w * w + h * h) / 2;
    if (a < b * 2) {
      h1 = d * cos(a - b) - w / 2;
      h2 = d * sin(a + b) - h / 2;
      h1 = h1 * h1 / (sin(a) * cos(a));
      h2 = h2 * h2 / (sin(a) * cos(a));
      printf("%.12f\n", w * h - (h1 + h2));
    } else {
      h1 = d * sin(a - b) - h / 2;
      h2 = d * sin(a + b) - h / 2;
      h1 = h1 * h1 / (sin(a) * cos(a));
      h2 = h2 * h2 / (sin(a) * cos(a));
      printf("%.12f\n", w * h - (h2 - h1));
    }
  }
  return 0;
}
