#include <bits/stdc++.h>
using namespace std;
int main() {
  double w, h, a;
  scanf("%lf%lf%lf", &w, &h, &a);
  if (w < h) swap(w, h);
  w /= 2, h /= 2;
  if (a > 90) a = 180 - a;
  if (a == 0) {
    printf("%lf\n", w * h * 4);
    return 0;
  }
  if (a == 90) {
    printf("%lf\n", min(w, h) * min(w, h) * 4);
    return 0;
  }
  a = a / 180.0 * acos(-1);
  double k = tan(a), x1 = -sin(a) * h, y1 = cos(a) * h, b = y1 - k * x1;
  double x2 = (h - b) / k, x3 = (-h - b) / k, y2 = -k * w + b;
  if (x2 >= -w && x2 <= w && x3 >= -w && x3 <= w) {
    printf("%lf\n", abs(x3 + x2) * h * 2);
  } else {
    double xx = x2 + w;
    double xx1 = w * 2 - xx / cos(a) - xx;
    printf("%.9lf\n", w * h * 4 - xx * xx * tan(a) - xx1 * xx1 / tan(a));
  }
  return 0;
}
