function Main(input) {
	input = parseInt(input, 10);
  // 入力
  if (input === 25) {
		console.log('Christmas');
	} else if (input === 24) {
		console.log('Christmas Eve');
	} else if (input === 23) {
		console.log('Christmas Eve Eve');
	} else if (input === 22) {
		console.log('Christmas Eve Eve Eve');
	}
}

Main(require("fs").readFileSync("/dev/stdin", "utf8"));