#include <bits/stdc++.h>

using namespace std;

int main() {
    //cin读入优化
    std::ios::sync_with_stdio(false);

    int h, r;
    cin >> h >> r;
    double v = (3.14 * r * r * h) / 1000; //一桶水的体积
    cout << ceil(20 / v) << endl; //向上取整

    //cout << floor(20 / v) << endl; //向下取整
    //cout << round(20 / v) << endl; //四舍五入取整
    return 0;
}