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 stdIn = new Scanner(System.in);
		List<Double> result = new ArrayList<Double>();
		
		int x = stdIn.nextInt(), h = stdIn.nextInt();
		while( x != 0 || h != 0 ){
			double th = (double)x*x/4 + h*h;
			double a = Math.sqrt(th);
			double b = 2*a*x+x*x;
			result.add(b);
			x = stdIn.nextInt();
			h = stdIn.nextInt();
		}
		
		for(Double ans : result){
			System.out.printf("%.6f%n", ans);
		}
	}
}