import java.util.*;

class Perimeter 
{
    public static void main(String[] args) 
    {
        Scanner sc = new Scanner(System.in);
        double a, s, p;
        System.out.println("Enter the area of a square:");
        a = sc.nextDouble();
        s = Math.sqrt(a);
        p = 4 * s;
        System.out.println("Perimeter=" + p);
    }
}