'use strict'

const main = (INPUT) => {
  const N = INPUT.split('\n')[0]
  if (N == 25) {
    console.log('Christmas');
  } else if (N == 24) {
    console.log('Christmas Eve');
  } else if (N == 23) {
    console.log('Christmas Eve Eve');
  } else if (N == 22) {
    console.log('Christmas Eve Eve Eve');
  }
}

main(require('fs').readFileSync('/dev/stdin', 'utf8'))
