ProblemB-Naieve.scala

package frl.driesprong

import scala.annotation.tailrec
import scala.io.Source


object ProblemB extends App {

  case class ProblemCase(pancakes: List[Boolean], K: Int)

  val lines = Source.fromFile("/Users/fokkodriesprong/Downloads/B-small-attempt0.in").getLines().toList

  @tailrec
  def checkMonotonicIncreasing(sequence: Array[Char]): Boolean =
    if (sequence.length > 1)
      if (sequence.head <= sequence.tail.head)
        checkMonotonicIncreasing(sequence.tail)
      else
        false
    else
      true


  @tailrec
  def solve(number: Long): Long =
    if (checkMonotonicIncreasing(number.toString.toArray))
      number
    else
      solve(number - 1)


  // Get rid of the number of tests
  val output = lines.tail.map(_.toLong).map(solve).zipWithIndex.map {
    case (output: Long, idx: Int) => s"Case #${idx + 1}: $output"
  }.mkString("\n")

  import java.io._

  val pw = new PrintWriter(new File("/Users/fokkodriesprong/Desktop/problemB.txt"))
  pw.write(output)
  pw.close()
}