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 P = pair<int, int>;

int main() {
    while (1) {
        int x, h;
        cin >> x >> h;
        if (!x) return 0;
        double l = sqrt(h * h + x * x * 0.25);
        printf("%.9lf\n", x * (x + l * 2));
    }
}