"use strict";
process.stdin.resume();
process.stdin.setEncoding("utf-8");

function print(x) {
  console.log(x);
}
let inputString = "";
let currentLine = 0;

process.stdin.on("data", (inputStdin) => {
  inputString += inputStdin;
});
process.stdin.on("end", () => {
  inputString = inputString.split("\n");
  main();
});
function readline() {
  return inputString[currentLine++];
}

// ************************ Code Start ***************************

function main() {

  var t = parseInt(readline());
  if (t == 25) print("Christmas");
  else if (t == 24) print("Christmas Eve");
  else if (t == 23) print("Christmas Eve Eve");
  else print("Christmas Eve Eve Eve"); 
}
