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 JAVA):

Solution:
import java.util.Scanner;

public class Main
{
	public static void main(String[] args)
	{
		Scanner scanner = new Scanner(System.in);
		
		for(; ;)
		{
			double x = scanner.nextDouble();
			double h = scanner.nextDouble();
			if(x==0 && h==0)
			{
				break;
			}
			
			System.out.println(String.format("%1$.6f", x*(x + 2*Math.sqrt((x*x)/4 + h*h))));
		}
	}
}