Problem: You are given two rectangles on a plane. The centers of both rectangles are located in the origin of coordinates (meaning the center of the rectangle's symmetry). The first rectangle's sides are parallel to the coordinate axes: the length of the side that is parallel to the Ox axis, equals w, the length of the side that is parallel to the Oy axis, equals h. The second rectangle can be obtained by rotating the first rectangle relative to the origin of coordinates by angle α.

<image>

Your task is to find the area of the region which belongs to both given rectangles. This region is shaded in the picture.

Input

The first line contains three integers w, h, α (1 ≤ w, h ≤ 106; 0 ≤ α ≤ 180). Angle α is given in degrees.

Output

In a single line print a real number — the area of the region which belongs to both given rectangles.

The answer will be considered correct if its relative or absolute error doesn't exceed 10 - 6.

Examples

Input

1 1 45


Output

0.828427125


Input

6 4 30


Output

19.668384925

Note

The second sample has been drawn on the picture above.

Solution (in CPP):

Solution:
#include <bits/stdc++.h>
#pragma GCC optimize("O3")
using namespace std;
unsigned seed = chrono::system_clock::now().time_since_epoch().count();
mt19937 eng(seed);
long long random2() { return (1ll << 31ll) * eng() + eng(); }
long long n, m, k, q, T;
const long long big = 1000000007;
const long long big2 = 1000000009;
const long long mod = 998244353;
template <class T>
int sgn(T x) {
  return (x > 0) - (x < 0);
}
template <class T>
struct Point {
  T x, y;
  explicit Point(T x = 0, T y = 0) : x(x), y(y) {}
  bool operator<(Point p) const { return tie(x, y) < tie(p.x, p.y); }
  bool operator==(Point p) const { return tie(x, y) == tie(p.x, p.y); }
  Point operator+(Point p) const { return Point(x + p.x, y + p.y); }
  Point operator-(Point p) const { return Point(x - p.x, y - p.y); }
  Point operator*(T d) const { return Point(x * d, y * d); }
  Point operator/(T d) const { return Point(x / d, y / d); }
  T dot(Point p) const { return x * p.x + y * p.y; }
  T cross(Point p) const { return x * p.y - y * p.x; }
  T cross(Point a, Point b) const { return (a - *this).cross(b - *this); }
  T dist2() const { return x * x + y * y; }
  double dist() const { return sqrt((double)dist2()); }
  double angle() const { return atan2(y, x); }
  Point unit() const { return *this / dist(); }
  Point perp() const { return Point(-y, x); }
  Point normal() const { return perp().unit(); }
  Point rotate(double a) const {
    return Point(x * cos(a) - y * sin(a), x * sin(a) + y * cos(a));
  }
  friend ostream& operator<<(ostream& os, Point p) {
    return os << "(" << p.x << "," << p.y << ")";
  }
};
template <class Point>
int sideOf(Point s, Point e, Point p) {
  return sgn(s.cross(e, p));
}
template <class Point>
int sideOf(const Point& s, const Point& e, const Point& p, double eps) {
  auto a = (e - s).cross(p - s);
  double l = (e - s).dist() * eps;
  return (a > l) - (a < -l);
}
template <class Point>
pair<int, Point> lineInter(Point s1, Point e1, Point s2, Point e2) {
  auto d = (e1 - s1).cross(e2 - s2);
  if (d == 0) return {-(s1.cross(e1, s2) == 0), Point(0, 0)};
  auto p = s2.cross(e1, e2), q = s2.cross(e2, s1);
  return {1, (s1 * p + e1 * q) / d};
}
int angDiff(array<Point<double>, 2> a, array<Point<double>, 2> b) {
  return sgn((a[1] - a[0]).angle() - (b[1] - b[0]).angle());
}
bool cmp(array<Point<double>, 2> a, array<Point<double>, 2> b) {
  int s = angDiff(a, b);
  return (s ? s : sideOf(a[0], a[1], b[0])) < 0;
}
vector<Point<double>> halfPlaneIntersection(
    vector<array<Point<double>, 2>> vs) {
  const double EPS = sqrt(2) * 1e-8;
  sort(vs.begin(), vs.end(), cmp);
  vector<array<Point<double>, 2>> deq((int)(vs).size() + 5);
  vector<Point<double>> ans((int)(vs).size() + 5);
  deq[0] = vs[0];
  int ah = 0, at = 0, n = (int)(vs).size();
  for (int i = 1; i < (n + 1); ++i) {
    if (i == n) vs.push_back(deq[ah]);
    if (angDiff(vs[i], vs[i - 1]) == 0) continue;
    while (ah < at && sideOf(vs[i][0], vs[i][1], ans[at - 1], EPS) < 0) at--;
    while (i != n && ah < at && sideOf(vs[i][0], vs[i][1], ans[ah], EPS) < 0)
      ah++;
    auto res = lineInter(vs[i][0], vs[i][1], deq[at][0], deq[at][1]);
    if (res.first != 1) continue;
    ans[at++] = res.second, deq[at] = vs[i];
  }
  if (at - ah <= 2) return {};
  return {ans.begin() + ah, ans.begin() + at};
}
const int MAXN = 300001;
template <class T>
T polygonArea2(vector<Point<T>>& v) {
  T a = v.back().cross(v[0]);
  for (int i = 0; i < ((int)(v).size() - 1); ++i) a += v[i].cross(v[i + 1]);
  return a;
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  long long a, b, c, d;
  long double w, h, ang;
  cin >> w >> h >> ang;
  ang *= 2 * acos(-1);
  ang /= 360.0;
  vector<array<Point<double>, 2>> lines;
  lines.push_back(
      {Point<double>(w / 2.0, h / 2.0), Point<double>(-w / 2.0, h / 2.0)});
  lines.push_back(
      {Point<double>(w / 2.0, -h / 2.0), Point<double>(w / 2.0, h / 2.0)});
  lines.push_back(
      {Point<double>(-w / 2.0, -h / 2.0), Point<double>(w / 2.0, -h / 2.0)});
  lines.push_back(
      {Point<double>(-w / 2.0, h / 2.0), Point<double>(-w / 2.0, -h / 2.0)});
  lines.push_back({Point<double>(w / 2.0, h / 2.0).rotate(ang),
                   Point<double>(-w / 2.0, h / 2.0).rotate(ang)});
  lines.push_back({Point<double>(w / 2.0, -h / 2.0).rotate(ang),
                   Point<double>(w / 2.0, h / 2.0).rotate(ang)});
  lines.push_back({Point<double>(-w / 2.0, -h / 2.0).rotate(ang),
                   Point<double>(w / 2.0, -h / 2.0).rotate(ang)});
  lines.push_back({Point<double>(-w / 2.0, h / 2.0).rotate(ang),
                   Point<double>(-w / 2.0, -h / 2.0).rotate(ang)});
  vector<Point<double>> hull = halfPlaneIntersection(lines);
  long double ans = polygonArea2<double>(hull) / 2.0;
  cout << setprecision(18) << abs(ans) << "\n";
  return 0;
}