class Point(xc: Int = 1, yc: Int = 2) {
  var _x: Int = xc
  var _y: Int = yc
  def getInstance: this.type = this

  def x: Int = _x
  def x_=(newX: Int): this.type = {
    _x = newX
    this
  }

  def y: Int = _y
  def y_=(newY: Int): this.type = {
    _y = newY
    this
  }
}

class Circle(xc: Int = 1, yc: Int = 2, rc: Int = 3) extends Point(xc, yc) {
  var _r: Int = rc

  def r: Int = _r
  def r_=(newR: Int): this.type = {
    _r = newR
    this
  }

}

class Cylinder(xc: Int = 1, yc: Int = 2, rc: Int = 3, hc: Int = 4)
    extends Circle(xc, yc, rc) {
  var _h: Int = hc

  def h: Int = _h
  def h_=(newH: Int): this.type = {
    _h = newH
    this
  }
}

val cyl = new Cylinder(1, 2)
val cir = new Circle(1, 2, 3)
val poi = new Point(1, 2)

poi.getInstance
cir.getInstance
cyl.getInstance

cyl.x = 2
cyl.r = 11
cyl.h = 1
cir.r = 4
cir.y = 12