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 eps = 1e-6;
struct halfplane {
  long double a, b, c;
};
long double faabs(long double a) { return a < 0 ? -a : a; }
halfplane draw(long double sx, long double sy, long double ex, long double ey,
               long double x, long double y) {
  halfplane p = {1.0 * (ey - sy), 1.0 * (sx - ex), -1};
  p.c = -p.a * sx - p.b * sy;
  if (p.a * x + p.b * y + p.c < 0) {
    p.a = -p.a;
    p.b = -p.b;
    p.c = -p.c;
  }
  return p;
}
long double ccw(pair<long double, long double> a,
                pair<long double, long double> b,
                pair<long double, long double> c) {
  long double dx1 = b.first - a.first;
  long double dy1 = b.second - a.second;
  long double dx2 = c.first - a.first;
  long double dy2 = c.second - a.second;
  return dx1 * dy2 - dy1 * dx2;
}
pair<long double, long double> cross(halfplane a, halfplane b) {
  long double det = a.a * b.b - a.b * b.a;
  long double d1 = a.b * b.c - a.c * b.b;
  long double d2 = a.c * b.a - a.a * b.c;
  if (faabs(det) < eps) return pair<long double, long double>(-1e9, -1e9);
  return pair<long double, long double>(d1 / det, d2 / det);
}
long double dist(pair<long double, long double> a,
                 pair<long double, long double> b) {
  return hypot(b.first - a.first, b.second - a.second);
}
long double solve(vector<halfplane> &v) {
  vector<pair<long double, long double> > pnts, calc;
  for (int i = 0; i < v.size(); i++) {
    for (int j = i + 1; j < v.size(); j++) {
      pair<long double, long double> t = cross(v[i], v[j]);
      if (t.first < -1e8) continue;
      bool bad = 0;
      for (int k = 0; k < v.size(); k++) {
        if (t.first * v[k].a + t.second * v[k].b + v[k].c < -eps) {
          bad = 1;
          break;
        }
      }
      if (!bad) pnts.push_back(t);
    }
  }
  if (pnts.empty()) return 0;
  for (auto &i : pnts) {
    bool bad = 0;
    for (auto &j : calc) {
      if (dist(i, j) < eps) {
        bad = 1;
        break;
      }
    }
    if (!bad) calc.push_back(i);
  }
  swap(calc[0], *min_element(calc.begin(), calc.end()));
  sort(calc.begin() + 1, calc.end(),
       [&](const pair<long double, long double> &a,
           const pair<long double, long double> &b) {
         long double tmp = ccw(calc[0], a, b);
         if (faabs(tmp) < eps) return dist(calc[0], a) < dist(calc[0], b);
         return tmp > 0;
       });
  long double ret = 0;
  for (int i = 1; i < calc.size() - 1; i++) {
    ret += ccw(calc[0], calc[i], calc[i + 1]);
  }
  return ret;
}
int main() {
  int w, h, ang;
  cin >> w >> h >> ang;
  vector<halfplane> v;
  pair<long double, long double> a[4] = {{1.0 * w, 1.0 * h},
                                         {1.0 * w, -1.0 * h},
                                         {-1.0 * w, -1.0 * h},
                                         {-1.0 * w, 1.0 * h}};
  for (int i = 0; i < 4; i++) {
    pair<long double, long double> p1 = a[i], p2 = a[(i + 1) & 3];
    v.push_back(draw(p1.first, p1.second, p2.first, p2.second, 0.0, 0.0));
  }
  long double rad = (acos(-1) * ang) / 180.0;
  for (int i = 0; i < 4; i++) {
    a[i] = pair<long double, long double>(
        a[i].first * cos(rad) - a[i].second * sin(rad),
        a[i].first * sin(rad) + a[i].second * cos(rad));
  }
  for (int i = 0; i < 4; i++) {
    pair<long double, long double> p1 = a[i], p2 = a[(i + 1) & 3];
    v.push_back(draw(p1.first, p1.second, p2.first, p2.second, 0.0, 0.0));
  }
  printf("%.10f", (double)solve(v) * 0.125);
}