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 sc = new Scanner(System.in);

		double x, h, h2 = 0;

		while(true){
			x = sc.nextInt();
			h = sc.nextInt();
			if(x == 0 && h == 0) break;

			h2 = Math.sqrt(Math.pow(x / 2, 2) + Math.pow(h, 2));

			System.out.println(x * x + 2 * x * h2);
		}
	}
}