function followers(input) {
  let obj = {};

  input.forEach(el => {
     let [command, ...rest] = el.split(": ");
      if (command === "Log out") {
      return;
});

    switch (command) {
      case "New follower":
        !obj[rest[0]] ? obj[rest[0]] = { likes: 0 } : ''
        break;

      case "Like":
        let username = rest[0];
        let likeCount = Number(rest[1]);
        !obj[username] ? obj[username] = { likes: likeCount } : obj[username].likes += likeCount;
        break;

      case "Comment":
        let userComment = rest[0];
        !obj[userComment] ? obj[userComment] = { likes: 1 } : obj[userComment].likes += 1;
        break;

      case "Blocked":
        let blocked = rest[0];
        obj[blocked] ? delete obj[blocked] : console.log(`${blocked} doesn't exist.`);
    }
  });
  console.log(`${Object.entries(obj).length} followers`);
  for (const info of Object.entries(obj)) {
    console.log(`${info[0]}: ${obj[info[0]].likes}`);
  }
}
followers([
  "Like: Katy: 3",
  "Comment: Katy",
  "New follower: Bob",
  "Blocked: Bob",
  "New follower: Amy",
  "Like: Amy: 4",
  "Log out",
]);