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(){
	double a,b;
	while(cin>>a>>b,a||b){
		double c=a*a;
		a/=2;
		double d=sqrt(b*b+a*a);
		c+=a*d*4;
		printf("%.10lf\n",c);
	}
}