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