#include<bits/stdc++.h>
using namespace std;
int main(){
    int r,h;
    float z,a,b;
    cin>>r>>h;
    a=r*r*3.1415926;
    b=r*2*3.1415926;
    z=a*2+b*h;
    printf("%.2f",z);
}
/**************************************************************
	Problem: 1623
	User: sucongyi
	Language: C++
	Result: Wrong Answer
****************************************************************/