#include <bits/stdc++.h>
using namespace std;
const double Pi = acos(-1.0);
inline int cmp(double x, double y = 0, double tol = 1e-8) {
  return (x <= y + tol) ? (x + tol < y) ? -1 : 0 : 1;
}
struct point {
  double x, y;
  point(double x = 0, double y = 0) : x(x), y(y) {}
  point operator+(point q) { return point(x + q.x, y + q.y); }
  point operator-(point q) { return point(x - q.x, y - q.y); }
  point operator*(double t) { return point(x * t, y * t); }
  point operator/(double t) { return point(x / t, y / t); }
  double operator*(point q) { return x * q.x + y * q.y; }
  double operator%(point q) { return x * q.y - y * q.x; }
  double mod() { return sqrt(x * x + y * y); }
  point rotate(double t) {
    return point(x * cos(t) - y * sin(t), x * sin(t) + y * cos(t));
  }
  int cmp(point q) const {
    if (int t = ::cmp(x, q.x)) return t;
    return ::cmp(y, q.y);
  }
  bool operator==(point q) const { return cmp(q) == 0; }
  bool operator!=(point q) const { return cmp(q) != 0; }
  bool operator<(point q) const { return cmp(q) < 0; }
  static point pivot;
};
point point::pivot;
double poly_area(vector<point>& T) {
  double s = 0;
  int n = T.size();
  for (int i = 0; i < n; i++) s += T[i] % T[(i + 1) % n];
  return s / 2;
}
point line_intersect(point p, point q, point r, point s) {
  point a = q - p, b = s - r, c = point(p % q, r % s);
  return point(point(a.x, b.x) % c, point(a.y, b.y) % c) / (a % b);
}
vector<point> halfplane(vector<point>& p, pair<point, point> semiplano) {
  vector<point> q;
  point p1 = semiplano.first, p2 = semiplano.second;
  int n = p.size();
  for (int i = 0; i < n; i++) {
    double c = (p2 - p1) % (p[i] - p1);
    double d = (p2 - p1) % (p[(i + 1) % n] - p1);
    if (cmp(c) >= 0) q.push_back(p[i]);
    if (cmp(c * d) < 0)
      q.push_back(line_intersect(p1, p2, p[i], p[(i + 1) % n]));
  }
  return q;
}
vector<point> semi_plano_cruzado(vector<pair<point, point> > semiplano) {
  vector<point> p;
  p.push_back(point(-1e9, -1e9));
  p.push_back(point(-1e9, +1e9));
  p.push_back(point(+1e9, +1e9));
  p.push_back(point(+1e9, -1e9));
  int n = semiplano.size();
  for (int i = 0; i < n; i++) {
    p = halfplane(p, semiplano[i]);
    if (p.size() == 0) break;
  }
  return p;
}
int main() {
  double w, h, a;
  cin >> w >> h >> a;
  double gama = atan(w / h);
  double beta = atan(h / w);
  vector<point> p, q;
  p.push_back(point(-0.5 * w, -0.5 * h));
  p.push_back(point(-0.5 * w, 0.5 * h));
  p.push_back(point(0.5 * w, 0.5 * h));
  p.push_back(point(0.5 * w, -0.5 * h));
  a = a * Pi / 180;
  double teta = 0.5 * Pi + a - gama - beta;
  q.push_back(point(-0.5 * w, -0.5 * h));
  q.push_back(point(-0.5 * w, 0.5 * h));
  q.push_back(point(0.5 * w, 0.5 * h));
  q.push_back(point(0.5 * w, -0.5 * h));
  for (int i = 0; i < 4; i++) q[i] = q[i].rotate(teta);
  for (int i = 0; i < 4; i++) {
    p = halfplane(p, make_pair(q[(i + 1) % 4], q[i]));
  }
  printf("%.9lf\n", fabs(poly_area(p)));
  return 0;
}
