TextMessagingOutrage.scala

object TextMessagingOutrage extends App {
  // incorrect results!!!

  def groupByK(sortedFreq: List[Int], K: Int): List[List[Int]] = {
    def padZero(freq: List[Int]): List[Int] = {
      val remainder = freq.size % K
      freq ++ Array.fill(remainder)(0).toList
    }

    if (sortedFreq.size < K) List(sortedFreq)
    else {
      val paddedFreq = padZero(sortedFreq)
  
      (for (i <- 0 until paddedFreq.size / K) yield {
        (for (j <- 0 until K) yield {
          paddedFreq(K * i + j)
        }).toList
      }).toList
    }
  }
  
  def calc(groupedFreq: List[List[Int]]): Int = {
    (for (i <- 0 until groupedFreq.size) yield {
      val group = groupedFreq(i)
      (i + 1) * group.sum
    }).sum
  }
  
  def solve(P: Int, K: Int, L: Int, freq: List[Int]): Int = {
    val sortedFreq = freq.sorted.reverse
    val groupedFreq = groupByK(sortedFreq, K)
    calc(groupedFreq)
  }

  //////////
  // main //
  //////////
  if (args.length > 0) Console.setIn(new java.io.FileInputStream(args(0)))
  if (args.length > 1) Console.setOut(new java.io.FileOutputStream(args(1)))
 
  for (t <- 1 to readInt) {
    val Array(p, k, l) = readLine.split(" ").map(_.toInt)
    val freq = readLine.split(" ").map(_.toInt).toList
    println(s"Case #${t}: ${solve(p, k, l, freq)}")
  }   
}