#include <bits/stdc++.h>
const double pi = acos(-1.0);
using namespace std;
int main() {
  double w, h;
  int temp;
  scanf("%lf%lf%d", &w, &h, &temp);
  if (temp % 90 == 0) {
    if (temp == 0 || temp == 180)
      printf("%.9lf\n", w * h);
    else
      printf("%.9lf\n", min(w, h) * min(w, h));
    return 0;
  }
  if (temp > 90) temp = 180 - temp;
  double angle = (double)temp * pi / 180;
  double x = sqrt(h * h + w * w) / 2;
  double flag_angle = acos(1 - h * h / (2 * x * x));
  flag_angle = min(flag_angle, pi - flag_angle);
  if (angle < flag_angle || fabs(w - h) < 1e-6) {
    double s1 = w / 2 - tan(angle / 2) * h / 2;
    s1 = s1 * s1 * tan(angle);
    double s2 = h / 2 - tan(angle / 2) * w / 2;
    s2 = s2 * s2 * tan(angle);
    printf("%.9lf\n", h * w - s1 - s2);
  } else {
    double edge = min(w, h);
    printf("%.9lf\n", edge * edge / sin(angle));
  }
}
