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 JAVA):

Solution:
import java.io.IOException;
import java.io.BufferedReader;
import java.io.InputStreamReader;

class Main{
    public static void main(String[] args) throws IOException{
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

        while(true){
            double x = Double.parseDouble(br.readLine());
            double h = Double.parseDouble(br.readLine());
            
            if(x == 0 && h == 0) break;

            double surface = x * x + 2 * x * Math.sqrt(x*x/4 + h*h);

            System.out.printf("%.6f\n",surface);
        }
    }
}