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 <stdio.h>
#include <math.h>

int main() {
    for (;;) {
        double x, h;
        scanf("%lf%lf", &x, &h);
        if (x == 0 && h == 0) return 0;
        const double y = sqrt(x*x/4+h*h);
        printf("%.6f\n", x*x+2*x*y);
    }
}