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){
	BufferedReader sc=new BufferedReader(new InputStreamReader(System.in));
	try {
	    while(true){
		double x = Double.valueOf(sc.readLine());
		double h = Double.valueOf(sc.readLine());
		if(x==0 && h==0)
		    break;
		System.out.println(x*x+2.0*x*Math.sqrt(h*h+(x/2)*(x/2)));
	    }
	}catch(Exception e){
	    System.out.println("Error");
	}
    }
}