cut chocolate

CutChocolate.scala

import scala.annotation.tailrec

case class Chocolate(height: Int, width: Int) {
  def cut: Option[(Chocolate, Chocolate)] = {
    if (height == 1 && width == 1) return None

    val (hs, ws) = (height, width) match {
      case (1, w) => ((1, 1), split(width))
      case (h, 1) => (split(height), (1, 1))
      case _ => if (randomBool) (split(height), (width, width)) else ((height, height), split(width))
    }
    Some(Chocolate(hs._1, ws._1), Chocolate(hs._2, ws._2))
  }

  private def split(thick: Int): (Int, Int) = {
    val one = thick / 2
    (one, thick - one)
  }

  private def randomBool: Boolean = scala.util.Random.nextBoolean()
}

@main def main: Unit =

  @tailrec
  def cutChocolates(chocolates: List[Chocolate], cut: Int): Int = {
    if (chocolates.isEmpty) cut
    else {
      val (choco, rest) = (chocolates.head, chocolates.tail)
      choco.cut match {
        case Some((c1, c2)) => cutChocolates(c1 :: c2 :: rest, cut + 1)
        case None => cutChocolates(rest, cut)
      }
    }
  }

  List((4, 3), (4, 4), (100, 123), (123, 100))
    .foreach { case (h, w) =>
    val chocolates = List(Chocolate(h, w))
    val result = cutChocolates(chocolates, 0)
    assert(result == h * w - 1, s"$h x $w: $result")
    println(s"$h x $w => ${result}")
  }