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;
  double y;
};
constexpr double PI = 3.141592653589793;
Point rotate(const Point &p, double angle) {
  double s = sin(angle);
  double c = cos(angle);
  double xnew = p.x * c - p.y * s;
  double ynew = p.x * s + p.y * c;
  return {xnew, ynew};
}
Point cross(const Point &p1, const Point &p2, const Point &p3,
            const Point &p4) {
  double divider =
      (p1.x - p2.x) * (p3.y - p4.y) - (p1.y - p2.y) * (p3.x - p4.x);
  double x = (p1.x * p2.y - p1.y * p2.x) * (p3.x - p4.x) -
             (p1.x - p2.x) * (p3.x * p4.y - p3.y * p4.x);
  x /= divider;
  double y = (p1.x * p2.y - p1.y * p2.x) * (p3.y - p4.y) -
             (p1.y - p2.y) * (p3.x * p4.y - p3.y * p4.x);
  y /= divider;
  return {x, y};
}
double distance(const Point &p1, const Point &p2) {
  return sqrt((p1.x - p2.x) * (p1.x - p2.x) + (p1.y - p2.y) * (p1.y - p2.y));
}
double area1(const Point &p1, const Point &p2, const Point &p3, const Point &p4,
             double h) {
  auto d1 = distance(p1, p2);
  auto d2 = distance(p3, p4);
  return (d1 + d2) * h;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);
  double w, h, alpha;
  cin >> w >> h >> alpha;
  if (h > w) swap(h, w);
  if (alpha > 90) alpha = 180 - alpha;
  alpha = alpha / 180 * PI;
  auto rp1 = rotate({w / 2, -h / 2}, alpha);
  auto rp2 = rotate({w / 2, h / 2}, alpha);
  auto rp3 = rotate({-w / 2, h / 2}, alpha);
  auto rp4 = rotate({-w / 2, -h / 2}, alpha);
  double threshold = atan(h / w) * 2;
  if (alpha == 0) {
    cout << fixed << setprecision(9) << w * h << endl;
    return 0;
  }
  if (alpha >= threshold) {
    auto p1 = cross({-w / 2, h / 2}, {w / 2, h / 2}, rp4, rp1);
    auto p2 = rotate({w / 2, -h / 2}, alpha);
    auto p3 = rotate({w / 2, h / 2}, alpha);
    auto p4 = cross({-w / 2, h / 2}, {w / 2, h / 2}, rp2, rp3);
    auto result = w * h - area1(p1, p2, p3, p4, h);
    cout << fixed << setprecision(9) << result << endl;
  } else {
    auto t1 = rp1;
    auto t2 = cross({w / 2, -h / 2}, {w / 2, h / 2}, rp4, rp1);
    auto t3 = cross({w / 2, -h / 2}, {w / 2, h / 2}, rp1, rp2);
    auto t4 = rp2;
    auto t5 = cross({w / 2, h / 2}, {-w / 2, h / 2}, rp1, rp2);
    auto t6 = cross({w / 2, h / 2}, {-w / 2, h / 2}, rp2, rp3);
    auto result = w * h;
    result -= distance(t1, t2) * distance(t1, t3);
    result -= distance(t4, t5) * distance(t4, t6);
    cout << fixed << setprecision(9) << result << endl;
  }
  return 0;
}