#include <stdio.h>
using namespace std;
int main() {
    const double PI = 3.1415926;
    double r, h;
    scanf("%lf %lf", &r, &h);
    double area = PI * r * r;
    double cir = 2 * PI * r;
    double surface = 2 * area + cir * h;
    printf("%.2lf\n", surface);
    return 0;
}
/**************************************************************
	Problem: 1623
	User: fuhoubin
	Language: C++
	Result: Accepted
	Time:10 ms
	Memory:1144 kb
****************************************************************/