function main(input) {
   input = input.trim();
  const a = input.split(" ").map(Number);
	console.log(a[0]==25?"Christmas"
			   :a[0]==24?"Christmas Eve"
			   :a[0]==23?"Christmas Eve Eve"
 	           :"Christmas Eve Eve Eve");
  
}
main(require('fs').readFileSync('/dev/stdin', 'utf8'));