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;

class Main {
	public static void main(String args[]){
		Scanner scan = new Scanner(System.in);
		double x,h,ans,tri;
		
		while(true){
			x = scan.nextDouble();
			h = scan.nextDouble();
			if(x==0&&h==0){
				break;
			}
			
			tri = Math.sqrt(x/2*x/2+h*h);
			
			ans = x*x + 4*(tri*x/2);
			System.out.printf("%.6f\n",ans);
		}
	}
}