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<bits/stdc++.h>
using namespace std;

int main(){
	while(true){
		double x, h;
		cin >> x >> h;
		
		if(x==0){
			break;
		}
		
		double H = sqrt(x*x*0.25+h*h);
		
		printf("%.5f\n",x*x + x*H/2.0*4.0);
	}
}