package kapitel_03

/**
 * Beispiel aus
 *
 * - Algorithmen und Datenstrukturen für Dummies
 *   - von Andreas Gogol-Döring und Thomas Letschert
 *   - Verlag Wiley-VCH; Oktober 2019
 *  - Kapitel 3, Daten und ihre Struktur
 *
 * @author A. Gogol-Döring, Th. Letschert
 */
object AuD_03_02_FArray_App extends App {

  def FArray1(n: Int): Array[Int] = {
    val a = new Array[Int](n+1)
    a(0) = 1
    for(i <- 1 to n)
      a(i) = a(i-1) * i
    a
  }

  def FArray2a(n: Int): Array[(Int, Int)] = {
    val a = new Array[(Int, Int)](n+1)
    a(0) = (0, 1)
    for(i <- 1 to n)
      a(i) = (i, a(i-1)._2 * i)
    a
  }

  def FArray2(n: Int): Array[(Int, Int)] = {
    val a = new Array[(Int, Int)](n+1)
    a(0) = (0, 1)
    for(i <- 1 to n)
      a(i-1) match {
        case (_, x) =>
          a(i) = (i, x * i)
      }
    a
  }


  case class Record(
    v: Int,
    f: Int
  )

  def FArray3a(n: Int): Array[Record] = {
    val a = new Array[Record](n+1)
    a(0) = Record(0, 1)
    for(i <- 1 to n)
      a(i) = Record(i, a(i-1).f * i)
    a
  }

  def FArray3(n: Int): Array[Record] = {
    val a = new Array[Record](n+1)
    a(0) = Record(0, 1)
    for(i <- 1 to n)
      a(i-1) match {
        case Record(_, v) =>
          a(i) = Record(i, v * i)
      }
    a
  }

  println(FArray1(10).mkString((",")))
  println(FArray2(10).mkString((",")))
  println(FArray3(10).mkString((",")))

}