#include<bits/stdc++.h>
using namespace std;
int main(){
	const double pi=3.1415926;
	float h,r,s,c,zs;
	cin>>r>>h;
	s=pi*r*r;
	c=pi*2*r;
	zs=s*2+c*h;
	printf("%.2f",zs);
	return 0;
}

/**************************************************************
	Problem: 1623
	User: tangkaixuan
	Language: C++
	Result: Wrong Answer
****************************************************************/