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;
const long double pi = atan(1.0) * 4.0;
const long double eps = 1e-4;
long double w, h, alpha;
struct pt {
  long double x, y;
  bool isEqual(pt o) { return (o.x == this->x && o.y == this->y); }
  string toString() { return "(" + to_string(x) + "," + to_string(y) + ")"; }
};
vector<pt> rect1, rect2;
pt originRotate(pt X, long double alpha) {
  return pt{X.x * cos(alpha) - X.y * sin(alpha),
            X.x * sin(alpha) + X.y * cos(alpha)};
}
struct line {
  long double a, b, c;
  string toString() {
    return to_string(a) + "x+" + to_string(b) + "y=" + to_string(c);
  }
};
struct segment {
  pt A, B;
};
line make_line(pt A, pt B) {
  pt u = pt{B.x - A.x, B.y - A.y};
  pt n = pt{-u.y, u.x};
  return line{n.x, n.y, A.x * n.x + A.y * n.y};
}
bool onLine(line l, pt P) { return (abs(l.a * P.x + l.b * P.y - l.c) < eps); }
bool between(long double a, long double b, long double c) {
  return (min(a, c) - eps <= b and b <= max(a, c) + eps);
}
bool between(pt A, pt B, pt C, bool debug = false) {
  line AC = make_line(A, C);
  return (onLine(AC, B) and between(A.x, B.x, C.x) and between(A.y, B.y, C.y));
}
pt lineIntersection(line d1, line d2, bool debug = false) {
  long double D = d1.a * d2.b - d1.b * d2.a;
  if (D == 0) return pt{nanl(" "), nanl(" ")};
  long double Dx = d1.c * d2.b - d1.b * d2.c;
  long double Dy = d1.a * d2.c - d1.c * d2.a;
  return pt{Dx / D, Dy / D};
}
pt segmentIntersection(pt A, pt B, pt C, pt D, bool debug = false) {
  line AB = make_line(A, B);
  line CD = make_line(C, D);
  pt I = lineIntersection(AB, CD, debug);
  if (debug) {
    cout << AB.toString() << '\n' << CD.toString() << '\n';
    cout << I.toString() << '\n';
  }
  if (isnan(I.x)) return pt{nanl(" "), nanl(" ")};
  if (between(A, I, B) and between(C, I, D)) return I;
  return pt{nanl(" "), nanl(" ")};
}
int determiningCase() {
  pt test = segmentIntersection(rect1[0], rect1[1], rect2[3], rect2[0], false);
  if (isnan(test.x)) return 2;
  return 1;
}
long double cross(pt A, pt B) { return (A.x * B.y - A.y * B.x); }
pt make_vector(pt A, pt B) { return pt{B.x - A.x, B.y - A.y}; }
long double area(pt A, pt B, pt C) {
  pt AB = make_vector(A, B);
  pt AC = make_vector(A, C);
  return 0.5 * abs(cross(AB, AC));
}
void solveCase1() {
  long double res = w * h;
  for (int i = 0; i < 4; i++) {
    long double A = area(rect1[i],
                         segmentIntersection(rect1[(i + 3) % 4], rect1[i],
                                             rect2[(i + 3) % 4], rect2[i]),
                         segmentIntersection(rect1[i], rect1[(i + 1) % 4],
                                             rect2[(i + 3) % 4], rect2[i]));
    res -= A;
  }
  cout << res;
}
void solveCase2() {
  pt I1 = segmentIntersection(rect1[0], rect1[1], rect2[0], rect2[1]);
  pt I2 = segmentIntersection(rect1[0], rect1[1], rect2[2], rect2[3]);
  long double w = abs(I1.x - I2.x);
  long double res = w * h;
  cout << res;
}
int main() {
  ios_base::sync_with_stdio(0);
  cin >> w >> h >> alpha;
  cout << setprecision(20) << fixed;
  if (h > w) swap(h, w);
  if (alpha == 0 or alpha == 180 or (alpha == 90 && w == h)) {
    cout << h * w;
    return 0;
  }
  alpha = min(alpha, 180 - alpha);
  alpha = alpha / 180.0 * pi;
  rect1.push_back(pt{w * 0.5, h * 0.5});
  rect1.push_back(pt{-w * 0.5, h * 0.5});
  rect1.push_back(pt{-w * 0.5, -h * 0.5});
  rect1.push_back(pt{w * 0.5, -h * 0.5});
  for (pt p : rect1) rect2.push_back(originRotate(p, alpha));
  int kase = determiningCase();
  if (kase == 1)
    solveCase1();
  else if (kase == 2)
    solveCase2();
  return 0;
}