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 <math.h>
#include <stdio.h>
using namespace std;

int main(void)
{
	double a, h;

	while (cin >> a >> h)
	{
		if (a == 0 && h == 0) break;
		double b = a / 2;
		double x = sqrt(b * b + h * h);
		printf("%.6f\n", a * a + (a * x * 0.5) * 4);
	}
	return 0;
}