var IsTest = false;
var Main = function(Input){
  var Arr = Input.split('\n');
  var Day = Arr[0];
  if(Day == '25'){
    console.log('Christmas');
  } else if(Day == '24'){
    console.log('Christmas Eve');
  } else if(Day == '23'){
    console.log('Christmas Eve Eve');
  } else if(Day == '22'){
    console.log('Christmas Eve Eve Eve');
  }
}

if(IsTest){
  Main(require("fs").readFileSync(__dirname+'/in.txt', "utf8"));  
} else {
  Main(require('fs').readFileSync('/dev/stdin', 'utf8'));
}

