val aToZ = ('a'..'z')
val countMap  = HashMap<Char, Int>().withDefault { 0 }

fun main(args: Array<String>) {
    while (true){
        val chars = readLine()?.map { when{ it.isUpperCase() -> it.toLowerCase() else -> it} } ?: break
        if (chars.isEmpty()) break
        chars.forEach {
            val count = countMap.getValue(it)
            countMap[it] = count + 1
        }
    }
    aToZ.forEach {
        println("$it : ${countMap.getValue(it)}")
    }
}
