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.*;
import java.io.*;
import static java.lang.Math.*;

class Main {

    public static void main( final String[] args ) {

	final Scanner stdin = new Scanner( System.in );

	while ( true ) {

	    final int x = stdin.nextInt();
	    final int h = stdin.nextInt();

	    if ( x == 0 && h == 0 ) {
		break;
	    }

	    final double S = x * x + 2.0 * x * sqrt( h * h + 0.25 * x * x );
	    
	    System.out.println( S );	    
	}	
    }    
}