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 PYTHON):

Solution:
import math

while True:
	try:
		x = input()
		h = input()
		if x == 0 and h == 0:
			break
		else:
			print '%6f' % float(x * math.sqrt(4 * h * h + x * x) + x * x)
	except EOFError:
		break