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;
using ll = long long;
using ull = unsigned long long;
using uint = unsigned int;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
using pld = pair<long double, long double>;
const double PI =
    3.14159265358979323846264338327950288419716939937510582097494459230781640628620899862;
const int inf_int = 1e9 + 5;
const ll inf_ll = 1e18 + 5;
const int NMax = 1e2 + 5;
const int dx[] = {-1, 0, 0, +1}, dy[] = {0, -1, +1, 0};
pld getIntersectionFromX(pld a, pld b, long double x) {
  long double slope = (b.second - a.second) / (b.first - a.first);
  long double yintercept = -slope * a.first + a.second;
  return {x, slope * x + yintercept};
}
pld getIntersectionFromY(pld a, pld b, long double y) {
  long double slope = (b.second - a.second) / (b.first - a.first);
  long double yintercept = -slope * a.first + a.second;
  return {(y - yintercept) / slope, y};
}
long double radToDeg(long double rad) { return rad * 180 / PI; }
long double degToRad(long double deg) { return deg * PI / 180.0l; }
int main() {
  cin.sync_with_stdio(false);
  cin.tie(0);
  ll w, h, angle;
  cin >> w >> h >> angle;
  if (w < h) {
    swap(w, h);
  }
  if (angle >= 90) {
    angle = 180 - angle;
  }
  if (angle == 0) {
    cout << w * h << '\n';
  } else if (angle == 90) {
    cout << min(w, h) * min(w, h) << '\n';
  } else {
    long double ldw = w, ldh = h, ldangle = angle;
    cout << fixed << setprecision(9);
    long double change = 2 * atan2(ldh, ldw);
    ldangle = degToRad(ldangle);
    if (ldangle >= change) {
      long double a =
          (angle < 90) ? (ldh / tan(ldangle)) : (ldh / tan(180 - ldangle));
      long double parallelogramBase = sqrt(a * a + ldh * ldh);
      cout << parallelogramBase * ldh << '\n';
    } else {
      pld s1[4], s2[4];
      s1[0] = {ldw / 2, -ldh / 2};
      s1[1] = {ldw / 2, ldh / 2};
      s1[2] = {-ldw / 2, ldh / 2};
      s1[3] = {-ldw / 2, -ldh / 2};
      for (int i = 0; i < 4; ++i) {
        s2[i].first = s1[i].first * cos(ldangle) - s1[i].second * sin(ldangle);
        s2[i].second = s1[i].first * sin(ldangle) + s1[i].second * cos(ldangle);
      }
      vector<pld> polygonPoints;
      polygonPoints.push_back(s2[0]);
      polygonPoints.push_back(getIntersectionFromX(s2[0], s2[1], ldw / 2));
      polygonPoints.push_back(s1[1]);
      polygonPoints.push_back(getIntersectionFromY(s2[0], s2[1], ldh / 2));
      polygonPoints.push_back(s2[1]);
      polygonPoints.push_back(getIntersectionFromY(s2[1], s2[2], ldh / 2));
      polygonPoints.push_back(s1[2]);
      polygonPoints.push_back(getIntersectionFromX(s2[1], s2[2], -ldw / 2));
      polygonPoints.push_back(s2[2]);
      polygonPoints.push_back(getIntersectionFromX(s2[2], s2[3], -ldw / 2));
      polygonPoints.push_back(s1[3]);
      polygonPoints.push_back(getIntersectionFromY(s2[2], s2[3], -ldh / 2));
      polygonPoints.push_back(s2[3]);
      polygonPoints.push_back(getIntersectionFromY(s2[3], s2[0], -ldh / 2));
      polygonPoints.push_back(s1[0]);
      polygonPoints.push_back(getIntersectionFromX(s2[3], s2[0], ldw / 2));
      polygonPoints.push_back(s2[0]);
      long double area = 0;
      polygonPoints.push_back(polygonPoints[0]);
      for (int i = 0; i < (int)polygonPoints.size() - 1; ++i) {
        area += polygonPoints[i].first * polygonPoints[i + 1].second -
                polygonPoints[i + 1].first * polygonPoints[i].second;
      }
      area /= 2;
      cout << 2 * ldw * ldh - area << '\n';
    }
  }
  return 0;
}