#include <bits/stdc++.h>
using namespace std;
const long long LLMAX = 0x7fffffffffffffffLL;
const long long LLMIN = 0x8000000000000000LL;
const int IMAX = 0x7fffffff;
const int IMIN = 0x80000000;
const double eps = 10e-7;
const int maxn = +10;
const double pi = 3.14159265;
double w, h, a, l1, l2;
int main() {
  while (~scanf("%lf%lf%lf", &w, &h, &a)) {
    if (a > 90.0) a = 180.0 - a;
    a = a * pi / 180.0;
    if (h > w) swap(h, w);
    l1 = h / 2.0 - w / 2.0 * tan(a / 2);
    l2 = w / 2.0 - h / 2.0 * tan(a / 2);
    if (tan(a / 2) > h / w)
      printf("%.8lf\n", h * h / sin(a));
    else
      printf("%.8lf\n", w * h - tan(a) * ((l1) * (l1) + (l2) * (l2)));
  }
  return 0;
}
