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 <cmath>
#include <cstdio>

using namespace std;

int main(int argc, char const* argv[])
{
	double x,h,S;

	while( cin >> x >> h && x != 0 ){
		double x2 = x/2;
		double l = sqrt( x2 * x2 + h * h );
		S = l * x * 2 + x * x;
		printf("%.6f\n",S);
	}
	return 0;
}