import scala.io.StdIn

object Main extends App {

  private val alphabets = Array.ofDim[Int](26)
  private val target = StdIn.readLine()
  
  target.foreach{ c =>
    val idx = c - 'a'
    if(idx >= 0) alphabets(idx) += 1
  }
  println(('a' to 'z').map(f => f.toString + " : " + alphabets(f - 'a')).mkString(f"%n"))
  
}
