object Main {
    val x = scala.collection.mutable.Map[Char, Int]().withDefaultValue(0)
    def main(args: Array[String]) = {
        for (line <- io.Source.stdin.getLines; c <- line) x((c.toLower)) += 1
        ('a' to 'z').foreach(c => println(c + " : " + x(c)))
    }
}

