object Main extends App {
  val in = io.Source.stdin.getLines.toIndexedSeq.head.toInt
  //println(in)
  if(in==25)
  	println("Christmas")
  else if(in==24)
    	println("Christmas Eve")
  else if(in==23)
    	println("Christmas Eve Eve")
          else if(in==22)
            	println("Christmas Eve Eve Eve")
  else
            	println("")
}
