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;

double x,y;

bool input(){
  cin>>x>>y;
  return (x!=0)||(y!=0);
}


double solve(){
  double tmp = sqrt((x/2)*(x/2)+y*y);
  return (x*x) + 4* x*tmp/2;
}

int main(){
  while(input()){
    cout<<setprecision(100)<<solve()<<endl;
  }
}