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;
struct Point {
  double x, y;
  Point() {}
  Point(double a, double b) {
    x = a;
    y = b;
  }
  double mod2() { return x * x + y * y; }
  double mod() { return sqrt(x * x + y * y); }
  double arg() { return atan2(y, x); }
  Point ort() { return Point(-y, x); }
  Point unit() {
    double k = mod();
    return Point(x / k, y / k);
  }
};
Point operator+(const Point &a, const Point &b) {
  return Point(a.x + b.x, a.y + b.y);
}
Point operator-(const Point &a, const Point &b) {
  return Point(a.x - b.x, a.y - b.y);
}
Point operator/(const Point &a, double k) { return Point(a.x / k, a.y / k); }
Point operator*(const Point &a, double k) { return Point(a.x * k, a.y * k); }
bool operator==(const Point &a, const Point &b) {
  return fabs(a.x - b.x) < 1e-6 && fabs(a.y - b.y) < 1e-6;
}
bool operator!=(const Point &a, const Point &b) { return !(a == b); }
bool operator<(const Point &a, const Point &b) {
  if (a.x != b.x) return a.x < b.x;
  return a.y < b.y;
}
double cross(const Point &A, const Point &B) { return A.x * B.y - A.y * B.x; }
double area(const Point &A, const Point &B, const Point &C) {
  return cross(B - A, C - A);
}
double Area(vector<Point> v) {
  int n = (int)v.size();
  double res = 0;
  for (int i = 1; i <= n - 2; i++) {
    double y = area(v[0], v[i], v[i + 1]);
    res += y;
  }
  return abs(res / 2);
}
bool between(const Point &A, const Point &B, const Point &P) {
  return P.x + 1e-6 >= min(A.x, B.x) && P.x <= max(A.x, B.x) + 1e-6 &&
         P.y + 1e-6 >= min(A.y, B.y) && P.y <= max(A.y, B.y) + 1e-6;
}
bool onSegment(const Point &A, const Point &B, const Point &P) {
  return abs(area(A, B, P)) < 1e-6 && between(A, B, P);
}
bool intersects(const Point &P1, const Point &P2, const Point &P3,
                const Point &P4) {
  double A1 = area(P3, P4, P1);
  double A2 = area(P3, P4, P2);
  double A3 = area(P1, P2, P3);
  double A4 = area(P1, P2, P4);
  if (((A1 > 0 && A2 < 0) || (A1 < 0 && A2 > 0)) &&
      ((A3 > 0 && A4 < 0) || (A3 < 0 && A4 > 0)))
    return true;
  else if (A1 == 0 && onSegment(P3, P4, P1))
    return true;
  else if (A2 == 0 && onSegment(P3, P4, P2))
    return true;
  else if (A3 == 0 && onSegment(P1, P2, P3))
    return true;
  else if (A4 == 0 && onSegment(P1, P2, P4))
    return true;
  else
    return false;
}
Point lineIntersection(const Point &A, const Point &B, const Point &C,
                       const Point &D) {
  return A + (B - A) * (cross(C - A, D - C) / cross(B - A, D - C));
}
vector<Point> inter(vector<Point> a, vector<Point> b) {
  int n = (int)a.size(), m = (int)b.size();
  vector<Point> I;
  for (int i = 0; i < n; i++)
    for (int j = 0; j < m; j++) {
      if (intersects(a[i], a[(i + 1) % n], b[j], b[(j + 1) % m])) {
        Point u = lineIntersection(a[i], a[(i + 1) % n], b[j], b[(j + 1) % m]);
        I.push_back(u);
      }
    }
  return I;
}
vector<Point> ConvexHull(vector<Point> Poly) {
  sort(Poly.begin(), Poly.end());
  int nP = Poly.size(), k = 0;
  Point H[2 * nP];
  for (int i = 0; i < nP; ++i) {
    while (k >= 2 && area(H[k - 2], H[k - 1], Poly[i]) <= 0) --k;
    H[k++] = Poly[i];
  }
  for (int i = nP - 2, t = k; i >= 0; --i) {
    while (k > t && area(H[k - 2], H[k - 1], Poly[i]) <= 0) --k;
    H[k++] = Poly[i];
  }
  if (k == 0) return vector<Point>();
  return vector<Point>(H, H + k - 1);
}
double angulo(double r) {
  if (r < 0) r += 2 * 3.14159265;
  return r;
}
int main() {
  double w, h, a;
  cin >> w >> h >> a;
  if (abs(a) < 1e-6) {
    printf("%f\n", w * h);
    return 0;
  }
  vector<Point> v;
  v.push_back(Point(h / 2, w / 2));
  v.push_back(Point(-h / 2, w / 2));
  v.push_back(Point(-h / 2, -w / 2));
  v.push_back(Point(h / 2, -w / 2));
  double x, y, x2, y2;
  vector<Point> v2;
  for (int i = 0; i < 4; i++) {
    x = (double)v[i].x, y = (double)v[i].y;
    x2 = x * cos((double)a * 3.14159265 / 180.0) -
         y * sin((double)a * 3.14159265 / 180.0);
    if (abs(x2) <= 1e-6) x2 = 0;
    y2 = x * sin((double)a * 3.14159265 / 180.0) +
         y * cos((double)a * 3.14159265 / 180.0);
    if (abs(y2) <= 1e-6) y2 = 0;
    v2.push_back(Point(x2, y2));
  }
  vector<Point> C = inter(v, v2);
  vector<Point> D;
  D = ConvexHull(C);
  printf("%f\n", Area(D));
  return 0;
}