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>
#pragma comment(linker, "/STACK:0x04000000")
using namespace std;
struct Point {
  long double x;
  long double y;
  Point(long double x = 0, long double y = 0) : x(x), y(y) {}
  Point Rotate(long double phi) {
    return Point(x * cosl(phi) - y * sinl(phi), y * cosl(phi) + x * sinl(phi));
  }
  long double Length() { return sqrtl(x * x + y * y); }
  Point LengthenIn(long double times) { return Point(x * times, y * times); }
};
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);
}
const long double PI = 3.14159265358979323846;
long double ToRadians(long double phi) { return phi / 180 * PI; }
vector<Point> polygon;
long double Dot(const Point &a, const Point &b) {
  return a.x * b.x + a.y * b.y;
}
long double Cross(const Point &a, const Point &b) {
  return a.x * b.y - a.y * b.x;
}
const long double EPS = 1e-4;
bool Equal(long double a, long double b) { return fabsl(a - b) < EPS; }
bool EqualOrLess(long double a, long double b) { return a - b < EPS; }
bool EqualOrMore(long double a, long double b) { return b - a < EPS; }
bool Less(long double a, long double b) { return b - a > EPS; }
bool More(long double a, long double b) { return a - b > EPS; }
Point IntersectionOfLines(const Point &a, const Point &b, const Point &c,
                          const Point &d) {
  Point new_c = c - a;
  Point new_d = d - a;
  Point new_b = b - a;
  long double length = new_b.Length();
  long double k = (new_d.x * new_c.y - new_c.x * new_d.y) /
                  (new_b.x * new_c.y - new_b.x * new_d.y + new_b.y * new_d.x -
                   new_b.y * new_c.x);
  Point intersection = new_b.LengthenIn(k);
  return a + intersection;
}
bool IsOnLine(const Point &a, const Point &b, const Point &c) {
  Point ca = a - c;
  Point cb = b - c;
  return Equal(Cross(ca, cb), 0) && EqualOrLess(Dot(ca, cb), 0);
}
void Process(const Point &a, const Point &b, const Point &c, const Point &d) {
  Point intersection = IntersectionOfLines(a, b, c, d);
  if (IsOnLine(a, b, intersection) && IsOnLine(c, d, intersection)) {
    polygon.push_back(intersection);
  }
}
bool LessComparer(const Point &a, const Point &b) {
  return Equal(a.x, b.x) ? Less(a.y, b.y) : Less(a.x, b.x);
}
vector<Point> down, up;
void Graham() {
  sort(polygon.begin(), polygon.end(), LessComparer);
  down.push_back(polygon.front());
  up.push_back(polygon.front());
  for (int i = 1; i < polygon.size(); i++) {
    while (down.size() > 1) {
      Point ab = down.back() - down[down.size() - 2];
      Point bc = polygon[i] - down.back();
      if (More(Cross(ab, bc), 0)) {
        break;
      }
      down.pop_back();
    }
    down.push_back(polygon[i]);
    while (up.size() > 1) {
      Point ab = up.back() - up[up.size() - 2];
      Point bc = polygon[i] - up.back();
      if (Less(Cross(ab, bc), 0)) {
        break;
      }
      up.pop_back();
    }
    up.push_back(polygon[i]);
  }
  reverse(up.begin(), up.end());
  polygon.assign(down.begin(), down.end() - 1);
  polygon.insert(polygon.end(), up.begin(), up.end() - 1);
}
long double Area() {
  polygon.push_back(polygon.front());
  long double area = 0;
  for (int i = 0; i < polygon.size() - 1; i++) {
    area += Cross(polygon[i], polygon[i + 1]);
  }
  area = fabsl(area) / 2;
  return area;
}
long double ToDegrees(long double phi) { return phi / PI * 180; }
int main() {
  long double w;
  long double h;
  int phi;
  cin >> w >> h >> phi;
  cout.setf(cout.fixed);
  cout.precision(20);
  if (phi == 0 || phi == 180) {
    cout << w * h << "\n";
    return 0;
  }
  if (phi == 90) {
    cout << min(w, h) * min(w, h) << "\n";
    return 0;
  }
  Point a(w / 2, h / 2);
  Point b(-w / 2, h / 2);
  Point c(-w / 2, -h / 2);
  Point d(w / 2, -h / 2);
  Point new_a = a.Rotate(ToRadians(phi));
  Point new_b = b.Rotate(ToRadians(phi));
  Point new_c = c.Rotate(ToRadians(phi));
  Point new_d = d.Rotate(ToRadians(phi));
  Process(a, b, new_a, new_b);
  Process(b, c, new_a, new_b);
  Process(c, d, new_a, new_b);
  Process(d, a, new_a, new_b);
  Process(a, b, new_b, new_c);
  Process(b, c, new_b, new_c);
  Process(c, d, new_b, new_c);
  Process(d, a, new_b, new_c);
  Process(a, b, new_c, new_d);
  Process(b, c, new_c, new_d);
  Process(c, d, new_c, new_d);
  Process(d, a, new_c, new_d);
  Process(a, b, new_d, new_a);
  Process(b, c, new_d, new_a);
  Process(c, d, new_d, new_a);
  Process(d, a, new_d, new_a);
  Graham();
  long double result = Area();
  cout << result << "\n";
}