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 s = new Scanner(System.in);
		for(;;){
			int x = s.nextInt();
			int h = s.nextInt();
			if(x==0)
				break;
			System.out.println(x*x+x*Math.sqrt(4*h*h+x*x));
		}
    }
}