const input = require('fs').readFileSync('/dev/stdin', 'utf8');

const output = () => {
  switch (input) {
    case '25':
      return 'Christmas';
      break;
    case '24':
      return 'Christmas Eve';
      break;
    case '23':
      return 'Christmas Eve Eve';
      break;
    case '22':
      return 'Christmas Eve Eve Eve';
      break;
  };
}

console.log(output());
