Ruby/Class/Virtual method

class Button
  def pushed
  end
end
buttonA = Button.new
def buttonA.pushed
  puts "BBB"
end
buttonB = Button.new
def buttonB.pushed
  puts "AAA"
end
 
Button.new.pushed
#
buttonA.pushed
# BBB
buttonB.pushed
# AAA

class Shape
end
class Square < Shape
  def initialize(side_length)
    @side_length = side_length
  end
  def area
    @side_length * @side_length
  end
  def perimeter
    @side_length * 4
  end
end
class Triangle < Shape
  def initialize(base_width, height, side1, side2, side3)
    @base_width = base_width
    @height = height
    @side1 = side1
    @side2 = side2
    @side3 = side3
  end
  def area
    @base_width * @height / 2
  end
  def perimeter
    @side1 + @side2 + @side3
  end
end
 
my_square = Square.new(5)
my_triangle = Triangle.new(6, 6, 7.81, 7.81, 7.81)
puts my_square.area
puts my_square.perimeter
puts my_triangle.area
puts my_triangle.perimeter