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;
long double EPS = 1e-12;
struct pt {
  long double x, y;
  pt(long double x, long double y) : x(x), y(y) {}
  pt operator+(const pt &first) const { return pt(x + first.x, y + first.y); }
  pt operator-(const pt &first) const { return pt(x - first.x, y - first.y); }
  pt operator*(long double c) const { return pt(x * c, y * c); }
  pt operator/(long double c) const { return pt(x / c, y / c); }
  bool operator==(const pt &first) const {
    return fabs(x - first.x) + fabs(y - first.y) < EPS;
  }
};
bool CONVEX;
long double dot(pt first, pt second) {
  return first.x * second.x + first.y * second.y;
}
long double cross(pt first, pt second) {
  return first.x * second.y - first.y * second.x;
}
long double dist2(pt first, pt second) {
  return dot(first - second, first - second);
}
long double dist(pt first, pt second) {
  return sqrt(dot(first - second, first - second));
}
bool clockwiseLL(pt a, pt b, pt c, pt d) { return cross(a - b, c - d) > 0; }
bool clockwisePPP(pt a, pt b, pt c) { return cross(a - c, a - b) > 0; }
pt intersectLL(pt a, pt b, pt c, pt d) {
  return a + (b - a) * (cross(c - a, c - d)) / (cross(b - a, c - d));
}
pt LINEA = pt(0, 0);
pt LINEB = pt(1, 2);
bool cmp4(pair<pt, pt> l, pair<pt, pt> m) {
  pt first = LINEA;
  pt second = LINEB;
  pt a = LINEA + l.second - l.first;
  pt b = LINEA + m.second - m.first;
  if (cross(a - first, a - second) * cross(b - first, b - second) >= 0) {
    if (cross(a - first, a - second) == 0 && dot(a - first, a - second) > 0)
      return true;
    if (cross(b - first, b - second) == 0 && dot(b - first, b - second) > 0)
      return false;
    return cross(b - first, a - first) < 0;
  }
  return cross(a - first, a - second) > 0;
}
long double areaG(vector<pt> g) {
  long double area = 0;
  for (int i = 0; i < g.size(); i++) {
    area += cross(g[i], g[(i + 1) % g.size()]);
  }
  return area / 2.0;
}
pt rotateP(pt first, long double t) {
  return pt(first.x * cos(t) - first.y * sin(t),
            first.x * sin(t) + first.y * cos(t));
}
vector<pt> rotateG(vector<pt> g, long double t) {
  vector<pt> h;
  for (int i = 0; i < g.size(); i++) {
    h.push_back(rotateP(g[i], t));
  }
  return h;
}
vector<pt> intersectionH(vector<pair<pt, pt> > v) {
  sort(v.begin(), v.end(), cmp4);
  CONVEX = true;
  vector<pair<pt, pt> > ans;
  vector<pt> pts;
  if (v.size() == 0) return pts;
  ans.push_back(v[0]);
  int ind = 1;
  while (v.size() > ind) {
    while (ans.size() > 1) {
      pair<pt, pt> a = v[ind];
      pair<pt, pt> b = ans[(long long)ans.size() - 2];
      pair<pt, pt> c = ans.back();
      if (!clockwiseLL(b.first, b.second, a.first, a.second) ||
          !clockwisePPP(intersectLL(b.first, b.second, c.first, c.second),
                        a.first, a.second))
        break;
      ans.pop_back();
    }
    ans.push_back(v[ind]);
    ind++;
  }
  LINEA = LINEA * -1;
  LINEB = LINEB * -1;
  v = ans;
  ans.clear();
  sort(v.begin(), v.end(), cmp4);
  ans.push_back(v[0]);
  ind = 1;
  while (v.size() > ind) {
    while (ans.size() > 1) {
      pair<pt, pt> a = v[ind];
      pair<pt, pt> b = ans[(long long)ans.size() - 2];
      pair<pt, pt> c = ans.back();
      if (!clockwiseLL(b.first, b.second, a.first, a.second) ||
          !clockwisePPP(intersectLL(b.first, b.second, c.first, c.second),
                        a.first, a.second))
        break;
      ans.pop_back();
    }
    ans.push_back(v[ind]);
    ind++;
  }
  LINEA = LINEA * -1;
  LINEB = LINEB * -1;
  for (int i = 0; i < ans.size(); i++) {
    pair<pt, pt> a = ans[i];
    pair<pt, pt> b = ans[(i + 1) % ans.size()];
    if (!clockwiseLL(a.first, a.second, b.first, b.second)) {
      CONVEX = false;
      cout << "Not convex!";
    }
    pts.push_back(intersectLL(a.first, a.second, b.first, b.second));
  }
  return pts;
}
vector<pt> intersectionGG(vector<pt> g, vector<pt> h) {
  vector<pair<pt, pt> > v;
  for (int i = 0; i < g.size(); i++) {
    v.push_back(make_pair(g[i], g[(i + 1) % g.size()]));
  }
  for (int i = 0; i < h.size(); i++) {
    v.push_back(make_pair(h[i], h[(i + 1) % h.size()]));
  }
  return intersectionH(v);
}
int main() {
  long double w, h, a;
  cin >> w >> h >> a;
  vector<pt> g;
  if (a == 0) a = 0.00000001;
  a = (a * atan(1)) / 45;
  g.push_back(pt(w / 2, h / 2));
  g.push_back(pt(-w / 2, h / 2));
  g.push_back(pt(-w / 2, -h / 2));
  g.push_back(pt(w / 2, -h / 2));
  cout << setprecision(10) << fixed;
  cout << areaG(intersectionGG(g, rotateG(g, a))) << endl;
}