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 CPP):

Solution:
#include <iostream>
#include <cstdio>
#include <cmath>
using namespace std;

int main(void){
	double x, h, a; //xは底面の1辺の長さ、hは錐の高さ、aは側面の高さ
	
	while(cin >> x >> h) {
		if(x == 0 && h == 0) break;
		
		a = sqrt(h*h + x*x/4);
		
		double S = x*x + x*a*2;
		
		printf("%.6lf\n", S);
	}
	
	return 0;
}