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;
#pragma comment(linker, "/STACK:200000000")
const double EPS = 1E-9;
const int INF = 1000000000;
const long long INF64 = (long long)1E18;
const double PI = 3.1415926535897932384626433832795;
struct pt {
  long double x, y;
  pt() {}
  pt(long double x, long double y) : x(x), y(y) {}
  bool operator<(const pt& p) const {
    return x < p.x - EPS || abs(x - p.x) < EPS && y < p.y - EPS;
  }
};
struct line {
  long double a, b, c;
  line() {}
  line(const pt& a, const pt& b) {
    this->a = a.y - b.y;
    this->b = -a.x + b.x;
    this->c = -a.x * this->a - a.y * this->b;
    long double t = sqrt(this->a * this->a + this->b * this->b);
    this->a /= t;
    this->b /= t;
    this->c /= t;
  }
  long double dist(const pt& p) { return a * p.x + b * p.y + c; }
};
pt a[110];
long double ans;
int n;
line perp(const pt& a, const pt& b) {
  line res;
  res.a = a.x - b.x;
  res.b = a.y - b.y;
  res.c = -res.a * (a.x + b.x) / 2 - res.b * (a.y + b.y) / 2;
  long double t = sqrt(res.a * res.a + res.b * res.b);
  res.a /= t;
  res.b /= t;
  res.c /= t;
  return res;
}
bool intersect(const line& l1, const line& l2, pt& res) {
  long double d = (l1.a * l2.b - l1.b * l2.a);
  if (abs(d) < EPS) return false;
  res.x = -(l1.c * l2.b - l1.b * l2.c) / d;
  res.y = -(l1.a * l2.c - l1.c * l2.a) / d;
  return true;
}
long double dist(const pt& a, const pt& b) {
  return sqrt((a.x - b.x) * (a.x - b.x) + (a.y - b.y) * (a.y - b.y));
}
int sg(long double a) {
  if (abs(a) < EPS) return 0;
  return a < 0 ? -1 : +1;
}
bool one_side(const pt& a, const pt& b, const pt& c, const pt& d) {
  line l(a, b);
  return sg(l.a * c.x + l.b * c.y + l.c) == sg(l.a * d.x + l.b * d.y + l.c);
}
bool inside(const pt& a, const pt& b, const pt& c, const pt& d) {
  return one_side(a, b, c, d) && one_side(a, c, b, d) && one_side(b, c, a, d);
}
vector<pair<long double, pt> > v;
void divide(vector<pt>& a, line l, int s) {
  vector<pt> res;
  for (int i = 0; i < (int)(a.size()); i++) {
    pt& cur = a[i];
    pt& to = a[(i + 1) % a.size()];
    if (sg(l.dist(cur)) == s || sg(l.dist(cur)) == 0) res.push_back(cur);
    if (sg(l.dist(cur)) * sg(l.dist(to)) < 0) {
      pt r;
      intersect(l, line(cur, to), r);
      res.push_back(r);
    }
  }
  a = res;
}
bool inside(vector<pt>& a, pt b) {
  bool res = false;
  for (int i = 0; i < (int)(a.size()); i++) {
    pt p = a[i], q = a[(i + 1) % a.size()];
    if (min(p.x, q.x) - EPS <= b.x && b.x < max(p.x, q.x) - EPS) {
      long double sy = p.y + (q.y - p.y) * (b.x - p.x) / (q.x - p.x);
      if (abs(sy - b.y) < EPS) return false;
      res ^= b.y < sy;
    }
  }
  return res;
}
long double vec(pt a, pt b, pt c) {
  return (b.x - a.x) * (c.y - a.y) - (b.y - a.y) * (c.x - a.x);
}
long double area(vector<pt> a) {
  long double res = 0;
  for (int i = 0; i < (int)(a.size() - 1); i++)
    res += vec(a[0], a[i], a[i + 1]);
  return abs(res) / 2;
}
void rot(pt& a, long double al) {
  long double x = a.x * cos(al) - a.y * sin(al);
  long double y = a.x * sin(al) + a.y * cos(al);
  a.x = x;
  a.y = y;
}
int main() {
  long double w, h, al;
  cin >> w >> h >> al;
  al = al / 180 * PI;
  vector<pt> a;
  a.push_back(pt(-w / 2, -h / 2));
  a.push_back(pt(+w / 2, -h / 2));
  a.push_back(pt(+w / 2, +h / 2));
  a.push_back(pt(-w / 2, +h / 2));
  vector<line> l;
  for (int i = 0; i < (int)(a.size()); i++) {
    pt p = a[i];
    pt q = a[(i + 1) % a.size()];
    rot(p, al);
    rot(q, al);
    l.push_back(line(p, q));
  }
  for (int i = 0; i < (int)(l.size()); i++)
    divide(a, l[i], sg(l[i].dist(pt(0, 0))));
  long double ans = area(a);
  cout.precision(20);
  cout << fixed << ans << endl;
  return 0;
}