function Main(input){

      input = parseInt(input,10);
  　input = Math.abs(25 - input);
  	
  
  
  
   process.stdout.write('Christmas');
  for(var i=0;i<input;i++){
    process.stdout.write(' Eve');
  }
  
  
}
 
Main(require("fs").readFileSync("/dev/stdin", "utf8"));