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 x, h;
  while (cin >> x >> h) {
    if (x == 0 && h == 0) break;
    double y = sqrt(h * h + (x * 0.5) * (x * 0.5));
    double ans = x * x + x * y * 0.5 * 4;
    cout << fixed << setprecision(6) << ans << endl;
  }
}