Java Program to Find Surface Area of Octahedron

import java.util.*;
class Main
{
    public static void main(String [] args)
    {
        int l = 3;
        // formula to find surface area of octahedron
        double ar = 2*(Math.sqrt(3))*(3*3);    
        System.out.println("The surface area of octahedron is: " + ar);
    }
}

Output:

The surface area of octahedron is: 31.17691453623979