function sub(foo) {
	foo = parseInt(foo);
    var str = "";
    if (foo == 25) {
        str = "Christmas";
    }
    if (foo == 24) {
        str = "Christmas Eve"
    }
    if (foo == 23) {
        str = "Christmas Eve Eve";
    }
    if (foo == 22) {
        str = "Christmas Eve Eve Eve";
    }
    return str;
}

function Main(ab) {
    console.log(sub(ab));
}

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