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.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Main {

	public static void main(String[] args) throws IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		String line = "";

		while ((line = br.readLine()) != null) {
			double x, h, xh;
			x = Double.parseDouble(line);
			h = Double.parseDouble(br.readLine());

			if (x == 0 && h == 0)
				break;

			xh = Math.sqrt(Math.pow(x / 2, 2) + Math.pow(h, 2));
			System.out.println(x * (xh * 2 + x));
		}
	}
}