using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Square Side a =  ");

        double a = double.Parse(Console.ReadLine());

        Console.WriteLine("Area = {0}",Geometry.SquareArea(a));

        Conosole.WriteLine("Perimeter = {0}",Geometry.SquarePerimeter(a));

}

​

 static class Geometry

{

    static double a;

    static double b;

    static double side;

    static double radius;

}

​

 public static double SquarePerimeter(double side);

   {

      return side*side;

   }

     public static double SquareArea(double side);

    {return side*side;}

     public static double RectanglePerimeter(double a, double );

    {return side*side;}

     public static double RectangleArea(double a, double b);

    {return side*side;}

    public static double CircleArea(double r);

    {return side*side;}