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;
const long double PI = acos(-1);
complex<long double> RotatePointAboutOrgin(complex<long double> p,
                                           long double angle_degree) {
  long double angle_rad = angle_degree * PI / 180.0;
  return complex<long double>(
      p.real() * cos(angle_rad) - p.imag() * sin(angle_rad),
      p.real() * sin(angle_rad) + p.imag() * cos(angle_rad));
}
bool intersect(const complex<long double>& a, const complex<long double>& b,
               const complex<long double>& p, const complex<long double>& q,
               complex<long double>& ret) {
  long double d1 = ((conj(p - a) * (b - a)).imag());
  long double d2 = ((conj(q - a) * (b - a)).imag());
  ret = (d1 * q - d2 * p) / (d1 - d2);
  if (fabs(d1 - d2) > 1e-9) return 1;
  return 0;
}
void polygonCut(const vector<complex<long double> >& p,
                const complex<long double>& a, const complex<long double>& b,
                vector<complex<long double> >& res) {
  res.clear();
  for (int i = 0; i < ((int)(p).size()); i++) {
    int j = (i + 1) % ((int)(p).size());
    bool in1 = ((conj(((b) - (a))) * (((p[i]) - (a)))).imag()) > 1e-9;
    bool in2 = ((conj(((b) - (a))) * (((p[j]) - (a)))).imag()) > 1e-9;
    if (in1) res.push_back(p[i]);
    if (in1 ^ in2) {
      complex<long double> r;
      intersect(a, b, p[i], p[j], r);
      res.push_back(r);
    }
  }
}
void convexPolygonIntersect(const vector<complex<long double> >& p,
                            const vector<complex<long double> >& q,
                            vector<complex<long double> >& res) {
  res = q;
  for (int i = 0; i < ((int)(p).size()); i++) {
    int j = (i + 1) % ((int)(p).size());
    vector<complex<long double> > temp;
    polygonCut(res, p[i], p[j], temp);
    res = temp;
    if (res.empty()) return;
  }
}
struct cmp {
  complex<long double> about;
  cmp(complex<long double> c) { about = c; }
  bool operator()(const complex<long double>& p,
                  const complex<long double>& q) const {
    long double cr = ((conj(((p) - (about))) * (((q) - (about)))).imag());
    if (fabs(cr) < 1e-9)
      return make_pair(p.imag(), p.real()) < make_pair(q.imag(), q.real());
    return cr > 0;
  }
};
void sortAntiClockWise(vector<complex<long double> >& pnts) {
  complex<long double> mn(1 / 0.0, 1 / 0.0);
  for (int i = 0; i < ((int)(pnts).size()); i++)
    if (make_pair(pnts[i].imag(), pnts[i].real()) <
        make_pair(mn.imag(), mn.real()))
      mn = pnts[i];
  sort((pnts).begin(), (pnts).end(), cmp(mn));
}
long double polygonArea(const vector<complex<long double> >& p) {
  long double res = 0;
  for (int i = 0; i < ((int)(p).size()); i++) {
    int j = (i + 1) % ((int)(p).size());
    res += ((conj(p[i]) * (p[j])).imag());
  }
  return fabs(res) / 2;
}
int main() {
  long double w, h, a;
  cin >> w >> h >> a;
  vector<complex<long double> > rec1, rec2, res;
  rec1.push_back(complex<long double>(-w / 2, -h / 2));
  rec1.push_back(complex<long double>(w / 2, -h / 2));
  rec1.push_back(complex<long double>(-w / 2, h / 2));
  rec1.push_back(complex<long double>(w / 2, h / 2));
  sortAntiClockWise(rec1);
  for (int i = 0; i < 4; i++) {
    rec2.push_back(RotatePointAboutOrgin(rec1[i], a));
  }
  sortAntiClockWise(rec2);
  convexPolygonIntersect(rec1, rec2, res);
  cout << fixed << setprecision(10) << polygonArea(res) << endl;
  return 0;
}