#include<iostream>
using namespace std;
int main()
{
	int h,r,a;
	double pi=3.14;
	cin>>h>>r;
	a=(pi*r*r*h)/1000;
	if(20%a==0)
	{
		cout<<20/a<<endl;
	}
	else
	cout<<(20/a)+1<<endl;
	return 0;
}