//作成日：4/20

//日付を受け取る変数
var day = Int(readLine()!)!

//条件分岐
if (day == 25){
  print ("Christmas")
}
else if (day == 24){
  print ("Christmas Eve")
}
else if (day == 23){
  print ("Christmas Eve Eve")
}
else{
  print ("Christmas Eve Eve Eve")
}