#include <bits/stdc++.h>
using namespace std;
int main() {
  long long w, h, b;
  while (~scanf("%lld%lld%lld", &w, &h, &b)) {
    if (b == 90) {
      long long tmp = min(w, h);
      long long ans = tmp * tmp;
      printf("%.9f\n", (double)ans);
      continue;
    }
    if (b == 0 || b == 180) {
      long long ans = w * h;
      printf("%.9f\n", (double)ans);
      continue;
    }
    if (b > 90) b = 180 - b;
    double a = 3.14159265358979323846 * (double)b / 180.0;
    double Sin = sin(a);
    double Cos = cos(a);
    double Tan = Sin / Cos;
    if (h > w) swap(h, w);
    double A = atan((double)h / (double)w) * 2;
    if (a < A) {
      double t = (Cos + 1) / Sin;
      double y = (h * t - w) / (t * t - 1);
      double x = (w - y) / t / Tan;
      double ans = w * h - x * x * Tan - y * y / Tan;
      printf("%.9f\n", ans);
    }
    if (a >= A) {
      double ans = (double)h * h / Sin;
      printf("%.9f\n", ans);
    }
  }
  return 0;
}
