#include <bits/stdc++.h>
using namespace std;
double w, h, alf, ok;
void read() {
  int a, b, c;
  cin >> a >> b >> c;
  if (a < b) {
    int temp = a;
    a = b;
    b = temp;
  }
  c = min(c, 180 - c);
  w = a;
  h = b;
  alf = c;
}
int main() {
  read();
  if (alf == 0)
    printf("%.9f\n", w * h);
  else if (alf == 90)
    printf("%.9f\n", h * h);
  else {
    alf = alf * 3.14159265358 / 180;
    ok = atan(h / w) * 2;
    if (alf < ok) {
      double x1 = cos(alf) * w / 2, y1 = sin(alf) * w / 2, k1 = -1 / tan(alf);
      double l1 = k1 * (w / 2 - x1) + y1;
      double x2 = sin(alf) * h / 2, y2 = -cos(alf) * h / 2, k2 = tan(alf);
      double l2 = k2 * (w / 2 - x2) + y2;
      double s1 = (h / 2 - l1) * (h / 2 - l1) * tan(alf);
      double s2 = (h / 2 + l2) * (h / 2 + l2) * (1 / tan(alf));
      printf("%.9f\n", w * h - s1 - s2);
    } else {
      double x = sin(alf) * h / 2, y = -cos(alf) * h / 2, k = tan(alf);
      printf("%.9f\n", (x - y / k) * 2 * h);
    }
  }
  return 0;
}
