using System;

namespace Geo
{   class Rectangle
    {   protected double width;
        protected double height;
        public double Width{get{return width;}}
        public double Height{get{return height;}}

        public Rectangle(double width, double height)
        {   if(width > 0 && height > 0)
			{   this.width = width;
                this.height = height;
            }
            else throw new ArgumentOutOfRangeException("bad data");
        }
    }
    class Square : Rectangle
    {   public Square(double size):base(size, size){} }

    class MutableRectangle : Rectangle
    {   public MutableRectangle(double width, double height) : base(width, height){}
        public void setWidth(double width)
        {   if(width>0) this.width = width;
            else throw new ArgumentOutOfRangeException("bad data");
        }
        public void setHeight(double height)
        {   if(height>0) this.height = height;
            else throw new ArgumentOutOfRangeException("bad data");
        }
    }
    class MutableSquare : Square
    {   public MutableSquare(double size):base(size){}
        public void setSize(double size)
        {   if(size>0)
            {   this.width=size;
                this.height=size;
            }
            else throw new ArgumentOutOfRangeException("bad data");}
    }
}