#include<bits/stdc++.h>
using namespace std;
int main(){
	float r,h;
	cin>>r>>h;
	printf("%.2f",(3.1415926*r*r)*2+(3.1415926*2*r)*h);
}
/**************************************************************
	Problem: 1623
	User: linzihang
	Language: C++
	Result: Accepted
	Time:16 ms
	Memory:2072 kb
****************************************************************/