func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     long long k;     cin >> k;     long long cnt = 0;     for (double a = 2 + 2. / 3; a < (2 * k) / sqrt(3); a += 2) {       double b =           1e-8 + (-a + sqrt((16 * k * k) / 3. - (3 * a * a))) / 2. - 2. / 3;       if (b > 0) cnt += ((int)b + 2) / 2;     }     cout << 1 + 6 * cnt << endl;     return 0;   }   