カリキュラム

const solution = (rule, design) => {
  const hash = rule
    .split('')
    .reduce((hash, subject) => ((hash[subject] = true), hash), {});
  rule = rule.split('');
  for (const subject of design) {
    if (hash.hasOwnProperty(subject)) {
      delete hash[subject];
      if (rule[0] == subject) rule.shift();
      else return 'NO';
    }
  }
  return 'YES';
};
const result = solution('CBA', 'CDAGBE');
console.log(result);