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 NumberFormatException, IOException {
		// TODO ?????????????????????????????????????????????
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		
		while(true){
			double x = Double.parseDouble(br.readLine());
			double h = Double.parseDouble(br.readLine());
			
			if(x == 0 && h == 0){
				break;
			}
			
			double result;
			//??´??¢???????§???¢?????????
			double h2 = Math.pow((h*h+x*x/4), 0.5);
			
			result = x*x + 4*(x*h2/2);
			
			System.out.printf("%.6f\n",result);
		}
	}

}