#include <bits/stdc++.h>
int main() {
  int w, h, alf;
  double wd, hd, alfd, ta, malf, x, y, x0, x1, x2, y0, y1, y2, tht, r, k;
  while (scanf("%d%d%d", &w, &h, &alf) != EOF) {
    if (w < h) {
      int temp = w;
      w = h;
      h = temp;
    }
    wd = (double)w;
    hd = (double)h;
    if (alf > 90) alf = 180 - alf;
    if (alf == 0)
      printf("%lf\n", (double)w * (double)h);
    else if (alf == 90)
      printf("%lf\n", (double)h * (double)h);
    else {
      alfd = (double)alf;
      alfd = alfd * acos(-1.0) / 180.0;
      k = tan(alfd);
      x = wd / 2;
      y = hd / 2;
      r = sqrt(x * x + y * y);
      tht = acos(x / r);
      malf = asin(y / r) + tht;
      x0 = r * cos(tht + alfd);
      y0 = r * sin(tht + alfd);
      y1 = y;
      x1 = (y1 - y0) / k + x0;
      ta = wd * hd;
      if (alfd < malf) {
        x2 = -x;
        y2 = k * (x2 - x0) + y0;
        double a = x + x1;
        double b = y - y2;
        double aa = wd - a - sqrt(a * a + b * b);
        double bb = aa / k;
        ta -= a * b + aa * bb;
      } else {
        y2 = -y;
        x2 = (y2 - y0) / k + x0;
        ta -= (wd + x1 + x2) * hd;
      }
      printf("%lf\n", ta);
    }
  }
  return 0;
}
