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;
using namespace std;

int main(){
double a,b;
while(1){
	cin>>a>>b;
	if(a==0&&b==0)break;
	printf("%.7f\n",a*a+sqrt((a/2.0)*(a/2.0)+b*b)*a/2.0*4.0);
}
}