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
#include <iostream>
#include <cmath>
#include <cstdio>
using namespace std;

int main() {
	int x, h;
	while (cin >> x >> h) {
		if (x == 0 && h == 0) break;
		printf("%.6lf\n", x * x + hypot(x / 2.0, h) * x * 2.0);
	}
}