import scala.io.StdIn

object Main extends App {
  val src: List[Char] = StdIn.readLine.toLowerCase.toList.init
  val acc: List[Int] = List.fill(26)(0)

  def counter(acc: List[Int], str: List[Char]): List[Int] = str match {
    case Nil => acc
    case h :: tail => if (122 >= h && h >= 97) counter(acc.updated(h-97, acc(h-97) + 1), tail)
                      else counter(acc, tail)
  }

  val pairs: List[List[AnyVal]] = List(('a' to 'z').toList, counter(acc, src)).transpose

  for {
    pair <- pairs
  } println(s"${pair(0)} : ${pair(1)}")
}