func_code_string: #include <bits/stdc++.h>   using namespace std;   const int oo = 1000000000;   const double H = sqrt(3.0) * 0.5;   const double eps = 1e-6;   int main() {     double r;     scanf( %lf , &r);     int i;     long long ans = 0;     for (i = 0; i <= r; i++) {       double x = 1.5 * i + 1.0;       if (x > r) break;       double y = sqrt(r * r - x * x);       int k;       if (i % 2)         k = (floor(y / H + eps) + 1) / 2;       else         k = floor(y / H + eps) / 2 + 1;       x = 1.5 * i + 0.5;       y = sqrt(r * r - x * x);       if (i % 2)         k = 2 * min(k, (int)floor(y / H + eps) / 2);       else         k = 2 * min(k, ((int)floor(y / H + eps) + 1) / 2) - 1;       ans += i ? 2 * k : k;     }     cout << ans << endl;   }   