Encapsulation

using System.IO;
using System;

class Rectangle
    {
      public double length, width;
      
      double GetArea()
      {
         return length * width;
      }
      public void Info()
      {
         Console.WriteLine("Length: {0}\nWidth: {1}", length, width);
         Console.WriteLine("Result: {0}", GetArea());
         Console.WriteLine("==========");
      }
   }
   
   class Square
   {
        double side;
        
        public Square(double s)
        {
            side = s;
        }
        double CountArea()
        {
            return side * side;    
        }
        public void Display()
        {
            Console.WriteLine("Side: {0}\nArea: {1}", side, CountArea());
            Console.WriteLine("==========");
        }
   }
   
   class Circle
   {
        const double pi = 3.14;
        double radius;
    
        public void UserInput()
        {
            Console.WriteLine("Enter radius:");
            radius = Convert.ToDouble(Console.ReadLine());
        }
        double Result()
        {
            return pi * radius * radius;
        }
        public void Details()
        {
            Console.WriteLine("Radius: {0}\nResult:{1}", radius, Result());
            Console.WriteLine("==========");
        }
   }
   
   class Program
   {
      static void Main(string[] args)
      {
         Rectangle r = new Rectangle();
         r.length = 5.8;
         r.width = 7.8;
         r.Info();
         
         Square s = new Square(5.89);
         s.Display();
         
         Circle c = new Circle();
         c.UserInput();
         c.Details();
         
         Console.ReadLine();
      }
   }