#include <stdio.h>

#define PI 3.1415926 

int main() {
    float r, h;
    scanf("%f %f", &r, &h);
    float area = 2 * PI * r * r + 2 * PI * r * h;
    printf("%.2f", area);
    return 0;
}
/**************************************************************
	Problem: 1623
	User: fuhoubin
	Language: C++
	Result: Wrong Answer
****************************************************************/