#include<bits/stdc++.h>
using namespace std;
int h,r;
double hh,rr,v;
#define PI 3.14
int main()
{
	cin>>h>>r;
	hh=h*0.1;
	rr=r*0.1;
	v=PI*rr*rr*hh;
	int temp=20/v;
	if(20-temp*v==0.0)
		cout<<temp;
	else
		cout<<(temp+1);
}