const main = input => {
  const D = input.trim()
  if (D === '25') {
    console.log('Christmas')
  } else if (D === '24') {
    console.log('Christmas Eve')
  } else if (D === '23') {
    console.log('Christmas Eve Eve')
  } else if (D === '22') {
    console.log('Christmas Eve Eve Eve')
  }
}
// 標準入力
main(require("fs").readFileSync("/dev/stdin", "utf8"));
