def coincidients(s1: Seq[Char], s2: Seq[Char]): Int = (s1, s2).zipped.count(p => (p._1 == p._2))
  def freqMap(s1: List[Char]) = s1.groupBy(_.toChar).mapValues(_.size)
  def estimate(s1: List[Char]): Int = if (s1 == Nil) 0 else List(0, freqMap(s1).maxBy(_._2)._2 - (s1.size / 2)).max

  def bestShuffle(s: String): Pair[String, Int] = {
    if (s == "") return ("", 0) else {}
    val charList = s.toList
    val estim = estimate(charList)