#include <bits/stdc++.h>
using namespace std;
const long double pi = 3.1415926535897932384626433832795;
long double x[42], y[42];
int n;
void add(int qx, int qy, long double ang) {
  x[n] = cos(ang) * qx - sin(ang) * qy;
  y[n] = sin(ang) * qx + cos(ang) * qy;
  n++;
}
void cut(long double xa, long double ya, long double xb, long double yb) {
  long double a = yb - ya, b = xa - xb;
  long double c = -a * xa - b * ya;
  long double eps = (1e-10) * 1.00042;
  int nn = 0;
  long double xx[42], yy[42];
  x[n] = x[0];
  y[n] = y[0];
  for (int i = 0; i < n; i++) {
    long double z1 = a * x[i] + b * y[i] + c;
    if (z1 < eps) {
      xx[nn] = x[i];
      yy[nn] = y[i];
      nn++;
    }
    long double z2 = a * x[i + 1] + b * y[i + 1] + c;
    if (z1 < eps && z2 > eps || z1 > eps && z2 < eps) {
      long double aa = y[i + 1] - y[i], bb = x[i] - x[i + 1];
      long double cc = -aa * x[i] - bb * y[i];
      long double d = a * bb - b * aa;
      xx[nn] = (b * cc - c * bb) / d;
      yy[nn] = (c * aa - a * cc) / d;
      nn++;
    }
  }
  n = nn;
  for (int i = 0; i < n; i++) x[i] = xx[i], y[i] = yy[i];
}
int main() {
  int w, h, iang;
  scanf("%d %d %d", &w, &h, &iang);
  long double ang = iang / 180.0 * pi;
  n = 0;
  add(w, h, ang);
  add(-w, h, ang);
  add(-w, -h, ang);
  add(w, -h, ang);
  cut(w, h, -w, h);
  cut(-w, h, -w, -h);
  cut(-w, -h, w, -h);
  cut(w, -h, w, h);
  x[n] = x[0];
  y[n] = y[0];
  long double area = 0;
  for (int i = 0; i < n; i++) area += (x[i] - x[i + 1]) * (y[i] + y[i + 1]);
  printf("%.17lf\n", (double)(0.125 * area));
  return 0;
}
