Problem: Create a program that outputs the surface area S of a square cone with a height of h, with a square with one side x as the base. However, assume that the line segment connecting the apex and the center of the base is orthogonal to the base. Also, x and h are positive integers less than or equal to 100.

Input

Given multiple datasets. Each dataset is given in the following format:


x
h


When both x and h are 0, it indicates the end of input.



Output

Output S (real number) on one line for each data set. The output may contain an error of 0.00001 or less.

Example

Input

6
4
7
9
0
0


Output

96.000000
184.192455

Solution (in CPP):

Solution:
#include <cstdio>
#include <cmath>
using namespace std;

double x, h;

int main() {
  while (1) {
    scanf("%lf", &x);
    scanf("%lf", &h);
    if (x == 0.0 && h == 0.0) return 0;

    printf("%f\n", x*x+x*sqrt(h*h+(x*x/4))*2);
  }
}