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>
using namespace std;
template <typename Arg1>
void prn(Arg1&& arg1) {
  cout << arg1 << "\n";
}
template <typename Arg1, typename... Args>
void prn(Arg1&& arg1, Args&&... args) {
  cout << arg1 << " ";
  prn(args...);
}
template <typename Arg1>
void prs(Arg1&& arg1) {
  cout << arg1 << " ";
}
template <typename Arg1, typename... Args>
void prs(Arg1&& arg1, Args&&... args) {
  cout << arg1 << " ";
  prs(args...);
}
template <typename Arg1>
void read(Arg1&& arg1) {
  cin >> arg1;
}
template <typename Arg1, typename... Args>
void read(Arg1&& arg1, Args&&... args) {
  cin >> arg1;
  read(args...);
}
namespace geometry {
struct pt {
  double x, y;
};
const double pi = 2. * acos(0);
double radian(double dgre) { return (pi * dgre) / 180; }
double degree(double rad) { return (180 * rad) / pi; }
double dist2(pt p) { return p.x * p.x + p.y * p.y; }
double dist(pt p) { return sqrtl(dist2(p)); }
pt operator-(pt p1, pt p2) { return {p1.x - p2.x, p1.y - p2.y}; }
pt operator+(pt p1, pt p2) { return {p1.x + p2.x, p1.y + p2.y}; }
pt operator*(pt p, double d) { return {p.x * d, p.y * d}; }
pt operator*(double d, pt p) { return {p.x * d, p.y * d}; }
pt operator/(pt p, double d) { return {p.x / d, p.y / d}; }
pt operator/(double d, pt p) { return {p.x / d, p.y / d}; }
pt perp(pt p) { return {-p.y, p.x}; }
double cross(pt p1, pt p2) { return p1.x * p2.y - p1.y * p2.x; }
double dot(pt p1, pt p2) { return p1.x * p2.x + p1.y * p2.y; }
pt rotl(pt p) { return {-p.y, p.x}; }
pt rotr(pt p) { return {p.y, -p.x}; }
pt rotate(pt p, double ang) {
  return {p.x * cos(ang) - p.y * sin(ang), p.x * sin(ang) + p.y * cos(ang)};
}
pt unit(pt p) { return p / dist(p); }
pt normal(pt p) { return unit(perp(p)); }
bool isParallel(pt a, pt b, pt c, pt d) { return cross(b - a, d - c) == 0; }
bool isColinear(pt a, pt b, pt c) { return cross(a - b, a - c) == 0; }
bool isColinear(pt a, pt b, pt c, pt d) {
  return isColinear(a, b, c) && isColinear(b, c, d);
}
bool isLeft(pt front, pt back, pt p) {
  return cross(front - back, p - back) > 0;
}
bool oppositeSides(pt a, pt b, pt c, pt d) {
  return isLeft(a, b, c) != isLeft(a, b, d);
}
bool isBetween(pt a, pt b, pt c) {
  if (!isColinear(a, b, c)) return 0;
  return min(a.x, b.x) <= c.x && c.x <= max(a.x, b.x) && min(a.y, b.y) <= c.y &&
         c.y <= max(a.y, b.y);
}
int lineIntersection(pt a, pt b, pt c, pt d, pt& res) {
  if (cross(b - a, d - c)) {
    res = c - (d - c) * cross(b - a, c - a) / cross(b - a, d - c);
    return 1;
  }
  return -isColinear(a, b, c, d);
}
double lineDist(pt a, pt b, pt p) {
  return abs(cross(b - a, p - a) / dist(b - a));
}
bool segmentIntersect(pt a, pt b, pt c, pt d) {
  if (isBetween(a, b, c) || isBetween(a, b, d) || isBetween(c, d, a) ||
      isBetween(c, d, b))
    return 1;
  return oppositeSides(a, b, c, d) && oppositeSides(c, d, a, b);
}
double segmentDistance(pt v, pt w, pt p) {
  double l2 = dist2(v - w);
  if (l2 == 0.0) return dist(p - v);
  double t = max(double(0), min(double(1), dot(p - v, w - v) / l2));
  pt projection = v + t * (w - v);
  return dist2(p - projection);
}
}  // namespace geometry
using namespace geometry;
double polygonArea(vector<pt>& vertices) {
  double ans = 0;
  for (int i = 1; i + 1 < vertices.size(); ++i)
    ans += cross(vertices[i] - vertices[0], vertices[i + 1] - vertices[0]);
  return abs(ans / 2.0);
}
inline void solve();
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int t = 1;
  for (int tc = 1; tc <= t; ++tc) {
    solve();
  }
  return 0;
}
bool cmp(pt a, pt b) { return a.x < b.x || (a.x == b.x && a.y < b.y); }
bool cw(pt a, pt b, pt c) {
  return a.x * (b.y - c.y) + b.x * (c.y - a.y) + c.x * (a.y - b.y) < 0;
}
bool ccw(pt a, pt b, pt c) {
  return a.x * (b.y - c.y) + b.x * (c.y - a.y) + c.x * (a.y - b.y) > 0;
}
void convex_hull(vector<pt>& a) {
  if (a.size() == 1) return;
  sort(a.begin(), a.end(), &cmp);
  pt p1 = a[0], p2 = a.back();
  vector<pt> up, down;
  up.push_back(p1);
  down.push_back(p1);
  for (int i = 1; i < (int)a.size(); i++) {
    if (i == a.size() - 1 || cw(p1, a[i], p2)) {
      while (up.size() >= 2 && !cw(up[up.size() - 2], up[up.size() - 1], a[i]))
        up.pop_back();
      up.push_back(a[i]);
    }
    if (i == a.size() - 1 || ccw(p1, a[i], p2)) {
      while (down.size() >= 2 &&
             !ccw(down[down.size() - 2], down[down.size() - 1], a[i]))
        down.pop_back();
      down.push_back(a[i]);
    }
  }
  a.clear();
  for (int i = 0; i < (int)up.size(); i++) a.push_back(up[i]);
  for (int i = down.size() - 2; i > 0; i--) a.push_back(down[i]);
}
inline void solve() {
  long long w, h, alfa;
  read(w, h, alfa);
  if (alfa % 180 == 0 || (w == h && alfa % 90 == 0)) {
    prn(w * h);
    return;
  }
  double theta = radian(alfa);
  vector<pt> v1;
  v1.push_back({w / 2., h / 2.});
  v1.push_back({-w / 2., h / 2.});
  v1.push_back({-w / 2., -h / 2.});
  v1.push_back({w / 2., -h / 2.});
  vector<pt> v2 = v1;
  for (auto& i : v2) {
    i = rotate(i, theta);
  }
  vector<pt> intersects;
  for (int i = 0; i < 4; ++i) {
    pt p1 = v1[i], p2 = v1[(i + 1) % 4];
    for (int j = 0; j < 4; ++j) {
      pt q1 = v2[j], q2 = v2[(j + 1) % 4];
      if (!segmentIntersect(p1, p2, q1, q2)) continue;
      pt res;
      int ret = lineIntersection(p1, p2, q1, q2, res);
      if (ret == -1) {
        prn(w * h);
        return;
      }
      assert(ret);
      intersects.push_back(res);
    }
  }
  convex_hull(intersects);
  cout << fixed << setprecision(10);
  prn(polygonArea(intersects));
}