Company Users JS Fundamentals

function companyEmployees(input) {
    let companies = {};

    for (let line of input) {
      let [company, employee] = line.split(" -> ");
      if (!companies.hasOwnProperty(company)) {
        companies[company] = new Set();
      }
      companies[company].add(employee);
    }

    let sortedCompanies = Object.keys(companies).sort();

    for (let company of sortedCompanies) {
      console.log(company);
      for (let employee of companies[company]) {
        console.log(`-- ${employee}`);
      }
    }
  }