s=require("fs").readFileSync("/dev/stdin","utf8");
if (s == "25") {
	console.log("Christmas");
} else if (s == "24") {
	console.log("Christmas Eve");
} else if (s == "23") {
	console.log("Christmas Eve Eve");
} else if (s == "22") {
	console.log("Christmas Eve Eve Eve");
}
