import java.util.*
fun main(args: Array<String>) {

    val D = readLine()!!.split(" ").map{it.toInt()}[0]
    println(
    when (D) {
        22-> "Christmas Eve Eve Eve"
        23-> "Christmas Eve Eve"
        24-> "Christmas Eve"
        25-> "Christmas"
        else-> "err"
    }
    )
}
