"use strict";
process.stdin.resume();
process.stdin.setEncoding("utf-8");
 
function print(x) {
  console.log(x);
}

let x = "", y = 0;
process.stdin.on("data", inputStdin => x += inputStdin);
process.stdin.on("end", () => {
  x = x.split("\n");
  main();
});
function readline() {
  return x[y++];
}
 

// ************************ Code Start ***************************
 
function main() {
 
  t = Number(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"); 
}
