#include <bits/stdc++.h>
using namespace std;
double find(double w, double h, double a) {
  a = a * 3.141592653589 / 180;
  double s = w * h, s1 = (h / 2 - w * tan(a / 2) / 2) *
                         (h / 2 - w * tan(a / 2) / 2) * tan(a);
  double s2 =
      (w / 2 - h * tan(a / 2) / 2) * (w / 2 - h * tan(a / 2) / 2) * tan(a);
  if (a <= 2 * atan(h / w))
    return s - s1 - s2;
  else
    return h * h / sin(a);
}
double w, h, a;
int main() {
  scanf("%lf%lf%lf", &w, &h, &a);
  if (w < h) swap(w, h);
  if (a > 90) a = 180 - a;
  double ans = find(w, h, a);
  printf("%.9lf\n", ans);
}
