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<cmath>
#include<cstdio>
using namespace std;
int main(){
  double a,b;
  while(cin >>a>>b,a||b){
    double x;
    x = sqrt(b*b+a*a/4);
    printf("%.6lf\n",a*a+x*a*2);
  }
  return 0;
}