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.*;
import java.util.*;

class Main {
	
	public static void main(String[] args) throws IOException {
		
		BufferedReader br = 
			new BufferedReader(new InputStreamReader(System.in));
		
		ArrayList<Double> ans = new ArrayList<Double>();
		
		while (true) {
			
			int x = Integer.parseInt(br.readLine());
			int h = Integer.parseInt(br.readLine());
			
			if (x == 0 && h == 0) break;
			ans.add(x * x + x * Math.sqrt(4.0 * h * h + x * x));
			
		}
		
		for (double d : ans) {
			System.out.printf("%.6f\n", d);
		}
		
	}
	
}