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 <iostream>
#include <cstdio>
#include <math.h>

using namespace std;

int main()
{
    double a, b;
    while (cin >> a >> b, a || b) {
        printf("%.9lf\n", a*a + a*2*sqrt((a*a)/4+b*b));
    }

    return 0;
}