https://gist.github.com/mtsmfm/4b8ffb53ffac055f5843

ramen-table.js

'use strict';

const STEAT_COUNTS = 8;

class Table {
  constructor() {
    this.first = new Seat(0);
    this.seats = [this.first]
    let preSeat = this.first;
    for (let i = 1; i < STEAT_COUNTS; i++) {
        const s = new Seat(i);
        this.seats.push(s);
        preSeat.setNextSeat(s);
        preSeat = s;
    }
    preSeat.setNextSeat(this.first);
  }

  toStatusString() {
    let s = '';
    this.seats.forEach((seat) => {
      s += seat.status;
    })
    return s;
  }

  toString() {
    let s = '';
    this.seats.forEach((seat) => {
      s += seat.isEmpty() ? '0' : '1';
    })
    return s;
  }

  //
  transit(count) {
    // 状態遷移させる
    this.seats.forEach((seat) => {
      seat.transit();
    })
    // 空いている席の最初のインデックスを取得
    const emptySeats = this.findEmptySeats(count);
    if (!emptySeats || emptySeats.length == 0) {
      return false;
    }
    if (emptySeats.length < count) {
      return false;
    }
    // 席を埋める
    for (let i = 0; i < count; i++) {
      emptySeats[i].take();
    }
    return true;
  }

  findEmptySeats(count) {
    let emptySeats = [];
    for (let searchStart = 0; searchStart < STEAT_COUNTS; searchStart++) {
      emptySeats = this._findEmptySeats(searchStart);
      if (!emptySeats || emptySeats.length == 0) {
        continue;
      }
      if (emptySeats.length < count) {
        continue;
      }
      return emptySeats;
    }
    return emptySeats;
  }

  _findEmptySeats(searchStart) {
    const startIndex = this.findEmptySeatStartIndex(searchStart);
    if (startIndex == -1) {
      return [];
    }
    const emptySeats = [];
    const start = this.seats[startIndex];
    let seat = start;
    while (seat.isEmpty()) {
      let next = seat.getNextSeat();
      emptySeats.push(seat);
      if (next === start) {
        return emptySeats;//全部空いている
      }
      seat = next;
    }
    return emptySeats;
  }

  findEmptySeatStartIndex(searchStart) {
    for (let i = searchStart; i < STEAT_COUNTS; i++) {
      if (this.seats[i].isEmpty()) {
        return i;
      }
    }
    return -1;
  }
}


const STATUS_EMTPY = 0;
const STATUS_WAITING = 1;
const STATUS_EATING = 2;
const STATUS_REST = 3;
class Seat {

  constructor(number) {
    this.empty = true;
    this.number = number;
    this.status = 0;
    this._nextSeat = null;
  }

  getNextSeat() {
    return this._nextSeat;
  }

   setNextSeat(seat) {
    this._nextSeat = seat;
  }

  transit() {
    if (this.status == STATUS_EMTPY) {
      return;
    }
    if (this.status == STATUS_REST) {
      this.status = STATUS_EMTPY;
    } else {
      this.status++;
    }
  }

  take() {
    this.status = STATUS_WAITING;
  }

  get getStatus() {
    return this.status;
  }

  isEmpty() {
    return this.status == STATUS_EMTPY;
  }
}

var assert = require('assert');

function test(input, output) {
  let table = new Table();
  let i = 0;
  //console.log("input:" + input);
  while (i != input.length) {
    if (table.transit(input[i])) {
      i++;
    }
    //console.log(table.toStatusString());
  }
  assert.equal(table.toString(), output);
}

test("3316", "11111110")
test("3342153", "11111111")
test("8", "11111111")
test("232624", "11110110")
test("1", "10000000")
test("224673432", "11111000")
test("123464334", "11111110")
test("44372332", "11111111")
test("2344", "11111111")
test("6448476233", "11111100")
test("4345174644", "11111111")
test("77743", "11111110")
test("2136524281", "10000000")
test("344373", "11100000")
test("434226", "11111111")
test("7433223", "11111110")
test("2246534", "11110111")
test("634", "11111110")
test("2222", "11111100")
test("2442343238", "11111111")
test("7243344", "11111111")
test("26147234", "10111111")
test("34424", "10011111")
test("6334", "11011111")
test("3828342", "11011110")
test("4431", "11110000")
test("2843212125", "11111111")
test("333336482", "11000000")
test("374", "11110000")
test("4382333", "11100111")