import std.stdio;
import std.string;
import std.conv;
import std.typecons;
import std.algorithm;
import std.functional;
import std.bigint;
import std.numeric;
import std.array;
import std.math;
import std.range;
import std.container;
import std.ascii;
import std.format;

void main()
{
	auto D = readln.chomp.to!int;
	switch(D)
	{
		case 22:
			writeln("Christmas Eve Eve Eve");
			break;
		case 23:
			writeln("Christmas Eve Eve");
			break;
		case 24:
			writeln("Christmas Eve");
			break;
		case 25:
			writeln("Christmas");
			break;
		default:
	}
}