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:

// 正四角錐の表面積の公式
// 底辺＊√（４＊高さ＊高さ＋底辺＊底辺）＋底辺＊底辺

#include <iostream>
#include <cmath>
#include <cstdio>

using namespace std;

int main(void){

  double x,h;
  while( cin >> x >> h , x || h ){
    double ans = x * sqrt( 4 * h * h + x * x ) + x * x;
    printf("%.6f", ans);
    cout << endl;

  }
  return 0;
}