import java.util.*;

fun main(args: Array<String>){
  val sc = Scanner(System.`in`)
  var day = sc.nextInt()
  if(day == 25){
    println("Christmas")
  }
  else if(day == 24){
    println("Christmas Eve")
  }
  else if(day == 23){
    println("Christmas Eve Eve")
  }
  else{
    println("Christmas Eve Eve Eve")
  }
}