04. Party Time js fundamentals

function solve(args) {
  const vipGuestsList = [];
  const regularGuestsList = [];

  const guestList = args.splice(0, args.indexOf('PARTY'));

  guestList.forEach((reservation) => {
    if (/^\d+/.test(reservation)) {
      vipGuestsList.push(reservation);
    } else {
      regularGuestsList.push(reservation);
    }
  });

  args.forEach((guest) => {
    if (vipGuestsList.indexOf(guest) >= 0) {
      vipGuestsList.splice(vipGuestsList.indexOf(guest), 1);
    }
    if (regularGuestsList.indexOf(guest) >= 0) {
      regularGuestsList.splice(regularGuestsList.indexOf(guest), 1);
    }
  });

  const allMissingGuest = [...vipGuestsList, ...regularGuestsList];

  console.log(allMissingGuest.length);
  vipGuestsList.forEach((el) => console.log(el));
  regularGuestsList.forEach((el) => console.log(el));
}