'use strict';
const main = input => {
  const d = parseInt(input[0], 10);
  switch (d) {
    case 25:
      console.log('Chiristmas');
      break;
    case 24:
      console.log('Chiristmas Eve');
      break;
    case 23:
      console.log('Chiristmas Eve Eve');
      break;
    case 22:
      console.log('Chiristmas Eve Eve Eve');
      break;
  
    default:
      break;
  }
}
main(require("fs").readFileSync("/dev/stdin", "utf8").split('\n'));