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.*;

public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		while ( true ) {
			double x = sc.nextDouble();
			double h = sc.nextDouble();
			if ( x == 0 && h == 0 ) break;
			double te = x*x;
			double h2 = Math.sqrt( ( (x/2) * (x/2) ) + (h*h));
			double tan = x * h2 / 2.0;
			System.out.printf("%.6f%n",te+tan*4);
		}
	}
}