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:100000000000000")
using namespace std;
long double sqr(long double x) { return x * x; }
long double abS(long double x) { return x < 0 ? -x : x; }
struct point {
  long double x, y;
  point(long double x, long double y) : x(x), y(y){};
  void read() { scanf("%lf%lf", &x, &y); };
  void print() { cout << fixed << setprecision(10) << x << " " << y; }
  point(){};
  point operator+(const point &s) const { return point(x + s.x, y + s.y); }
  bool operator<(const point &s) const {
    return (x < s.x || (x == s.x && y < s.y));
    return false;
  }
  point operator-(const point &s) const { return point(x - s.x, y - s.y); }
  bool operator==(const point &f) {
    return (abS(x - f.x) <= 1e-1 && abS(y - f.y) <= 1e-1);
  };
  point operator*(long double d) { return point(x * d, y * d); }
  long double operator*(point a) { return a.x * x + a.y * y; };
  long double d() { return sqrt(sqr(x) + sqr(y)); }
  point norm() { return point(x / d(), y / d()); }
  long double vec_m(point s) { return x * s.y - y * s.x; }
  point operator-() { return point(-x, -y); };
};
struct line {
  long double a, b, c;
  point bound1, bound2, sun_beg, sun_en;
  line(point f, point s) {
    a = s.y - f.y;
    b = f.x - s.x;
    c = -(a * f.x + f.y * b);
    bound1 = point((-1e20), -(-1e20));
    bound2 = point((-1e20), -(-1e20));
    sun_beg = point(-1e20, -1e20);
    sun_en = point(-1e20, -1e20);
  };
  line(long double a, long double b, long double c)
      : a(a), b(b), c(c), bound1(-1e20, - -1e20), bound2(-1e20, - -1e20){};
  void set_bounds(point f, point s) {
    bound1 = point(min(f.x, s.x), max(f.x, s.x));
    bound2 = point(min(f.y, s.y), max(f.y, s.y));
    sun_beg = f;
    sun_en = s;
  }
  void set_bounds_sun(point beg, point en) {
    bound1 =
        point(beg.x >= en.x ? -1e20 : beg.x, beg.x < en.x ? - -1e20 : beg.x);
    bound2 =
        point(beg.y >= en.y ? -1e20 : beg.y, beg.y < en.y ? - -1e20 : beg.y);
    sun_beg = beg;
  }
  bool into(point f) {
    return (abS(f.x * a + f.y * b + c) <= 1e-1 && (f.x - bound1.x) > -1e-1 &&
            (-f.x + bound1.y) > -1e-1 && (f.y - bound2.x) > -1e-1 &&
            (-f.y + bound2.y) > -1e-1);
  }
  long double d_to_point(point smth) {
    return (a * smth.x + b * smth.y + c) / sqrt(sqr(a) + sqr(b));
  }
  long double d_to_point_sp(point smth) {
    if (smth == point(-1e20, -1e20)) return - -1e20;
    long double d = abS((a * smth.x + b * smth.y + c) / sqrt(sqr(a) + sqr(b)));
    point temp = point(a, b).norm() * d;
    if (into(smth + temp) || into(smth + (-temp))) return d;
    return min((sun_beg - smth).d(), (sun_en - smth).d());
  }
  void line_from_point_and_norm(point f, point norm) {
    a = norm.x;
    b = norm.y;
    c = -(a * f.x + b * f.y);
  }
  line() {
    bound1 = point(-1e20, - -1e20);
    bound2 = point(-1e20, - -1e20);
  };
  point intrsc(line f) {
    if (a * f.b - b * f.a == 0) return point(-1e20, -1e20);
    long double x = (b * f.c - c * f.b) / (a * f.b - b * f.a);
    long double y = (c * f.a - a * f.c) / (a * f.b - b * f.a);
    if (!into(point(x, y)) || !f.into(point(x, y))) return point(-1e20, -1e20);
    return point(x, y);
  }
  long double d(line to) {
    point o = intrsc(to);
    return min(d_to_point_sp(to.sun_beg),
               min(d_to_point_sp(to.sun_en),
                   min(to.d_to_point_sp(sun_beg),
                       min(to.d_to_point_sp(sun_en), to.d_to_point_sp(o)))));
  }
  line operator-() { return line(-a, -b, -c); };
  void read() { cin >> a >> b >> c; }
  long double take_y_from_x(long double x) { return (-c - a * x) / b; }
};
long double take_tr_S(point f, point s, point d) {
  return (s.x - f.x) * (d.y - f.y) - (s.y - f.y) * (d.x - f.x);
}
long double take_S(vector<point> go) {
  long double sum = 0;
  for (long long int i = 0; i < go.size(); i++) {
    sum += (take_tr_S(go[0], go[i], go[(i + 1) % go.size()]));
  }
  return abS(sum) / 2.0;
}
point takeit(point av, long double an, long double w, long double h) {
  point vec = av - point(w / 2, h / 2);
  point temp = point(vec.x * cos(an) - vec.y * sin(an),
                     vec.y * cos(an) + vec.x * sin(an));
  return point(w / 2, h / 2) + temp;
}
int main() {
  long double w, h, an;
  cin >> w >> h >> an;
  if (w < h) swap(w, h);
  if (an > 90) an = 180 - an;
  an = 3.14159265358979323 * (an / 180);
  line a, b, c, d;
  a = line(point(0, 0), point(0, h));
  a.set_bounds(point(0, 0), point(0, h));
  b = line(point(0, h), point(w, h));
  b.set_bounds(point(0, h), point(w, h));
  c = line(point(w, h), point(w, 0));
  c.set_bounds(point(w, h), point(w, 0));
  d = line(point(0, 0), point(w, 0));
  d.set_bounds(point(0, 0), point(w, 0));
  point na, nb, nc, nd, temp;
  na = takeit(point(0, 0), an, w, h);
  nb = takeit(point(0, h), an, w, h);
  nc = takeit(point(w, h), an, w, h);
  nd = takeit(point(w, 0), an, w, h);
  line la, lb, lc, ld;
  la = line(na, nb);
  la.set_bounds(na, nb);
  lb = line(nb, nc);
  lb.set_bounds(nb, nc);
  lc = line(nc, nd);
  lc.set_bounds(nc, nd);
  ld = line(na, nd);
  ld.set_bounds(na, nd);
  temp = a.intrsc(lb);
  long double si = 0;
  vector<point> ag;
  if (!(temp == point(-1e20, -1e20))) {
    ag.push_back(temp);
    ag.push_back(nb);
    ag.push_back(la.intrsc(a));
    si += take_S(ag);
    ag.clear();
    ag.push_back(lb.intrsc(b));
    ag.push_back(nc);
    ag.push_back(lc.intrsc(b));
    si += take_S(ag);
    si *= 2;
  } else {
    ag.push_back(lb.intrsc(b));
    ag.push_back(nc);
    ag.push_back(nd);
    ag.push_back(ld.intrsc(b));
    si = take_S(ag);
    si *= 2;
  }
  cout << fixed << setprecision(10) << w * h - si;
}