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 in = new Scanner(System.in);
		while(true){
			int x = in.nextInt();
			int h = in.nextInt();
			if(x + h == 0)break;
			double x2 = x;
			double h2 = h;
			double S = x2*x2 +2*x2*Math.sqrt((x2*x2)/4+h2*h2);
			System.out.println(S);
		}
	}
}