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 stdIn = new Scanner(System.in);

	double x, h;
	double s, t1, t2;
	while (true) {
	    x = stdIn.nextInt();
	    h = stdIn.nextInt();
	    if (x == 0 && h == 0) break;

	    t1 = h * h + x * x / 4;
	    t2 = Math.sqrt(t1);
	    s = x * x + 2 * x * t2;
	    System.out.println(s);
	}
    }
}