#include <bits/stdc++.h>
using namespace std;
const long long maxn = 100010;
const long long mod = 100007;
const long long N = 500 + 7;
const long long inf = 0x3f3f3f3f;
const double eps = 1e-8;
const double PI = acos(-1);
long long n, m, cnt, ans, flag;
inline long long read() {
  register long long c = getchar(), fg = 1, sum = 0;
  while (c > '9' || c < '0') {
    if (c == '-') fg = -1;
    c = getchar();
  }
  while (c <= '9' && c >= '0') {
    sum = sum * 10 + c - '0';
    c = getchar();
  }
  return fg * sum;
}
double a, b, k;
void init() {
  cin >> a >> b >> k;
  k = k / 180 * PI;
}
void go() {
  k = min(k, PI - k);
  if (k == 0.0) {
    printf("%.10f\n", a * b);
    return;
  }
  if (a > b) swap(a, b);
  if (a / sin(k) + a / tan(k) > b) {
    double x = (b - (a + a * cos(k)) / sin(k)) /
               (sin(k) - (1 + cos(k)) * (1 + cos(k)) / sin(k));
    double s = sin(k) * x * cos(k) * x;
    double y = a - x - cos(k) * x;
    printf("%.10f\n", a * b - s - y * y / tan(k));
    return;
  }
  printf("%.10f\n", a * a / sin(k));
}
signed main() {
  init();
  go();
}
