text: import { NotImplementedError } from '../extensions/index.js';
  
  /**
   * Given an array of domains, return the object with the appearances of the DNS.
   *
   * @param {Array} domains
   * @return {Object}
   *
   * @example
   * domains = [
   *  'code.yandex.ru',
   *  'music.yandex.ru',
   *  'yandex.ru'
   * ]
   *
   * The result should be the following:
   * {
   *   '.ru': 3,
   *   '.ru.yandex': 3,
   *   '.ru.yandex.code': 1,
   *   '.ru.yandex.music': 1,
   * }
   *
   */
  export default function getDNSStats(domains) {
    let res = {};
    for (let item of domains) {
      let curr = item.split('.').reverse();
      let str = '';
      for (let x of curr) {
        str += '.' + x;
        if (!res[str]) {
          res[str] = 1;
        } else {
          res[str]++;
        }
      }
    }
    return res;
  }