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.*;

class Main {
	Scanner sc = new Scanner(System.in);


	public void run() {
		while(true){
			int x=sc.nextInt(),h=sc.nextInt();
			if(x==0 && h==0)break;
			ln(x*(x+Math.sqrt(x*x+4*h*h)));
		}

	}

	public static void main(String[] args) {
		new Main().run();
	}

	public static void pr(Object o) {
		System.out.print(o);
	}

	public static void ln(Object o) {
		System.out.println(o);
	}

	public static void ln() {
		System.out.println();
	}
}