import java.util.*

fun main(args: Array<String>) {
    val scanner = Scanner(System.`in`)

    tailrec fun printCase(no: Int) {
        val x =scanner.nextInt()
        if (x != 0) {
            println("Case ${no}: ${x}")
            printCase(no + 1)
        }
    }
    printCase(1)
}

