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.*;

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