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(){
  while(true){
    int x,h;
    scanf("%d%d",&x,&h);
    if(x+h==0)return 0;
    // x/2, h, ?
    double sha = sqrt(x*x/4.0 + 1.0*h*h);
    double ans = x*x*1.0 + 4.0*x*sha/2.0;
    printf("%.9f\n",ans);
  }
}