queueDemo.js

function Queue() {
  let items = [];
  this.enqueue = function (element) {
    items.push(element);
  };
  this.dequeue = function () {
    return items.shift();
  };
  this.front = function () {
    return items[0] ? items[0] : "数组为空";
  };
  this.isEmpty = function () {
    return items.length === 0;
  };
  this.size = function () {
    return items.length;
  };
  this.print = function () {
    console.log(items.toString());
  };
}

// 循环队列，模拟击鼓传花
function hotPotato(nameList, num) {
  let queue = new Queue();
  for (let i = 0; i < nameList.length; i++) {
    queue.enqueue(nameList[i]);
  }
  let result = "";
  while (queue.size() > 1) {
    for (let i = 0; i < num; i++) {
      queue.enqueue(queue.dequeue());
    }
    result = queue.dequeue();
    console.log(`${result} 被淘汰了`);
  }
  console.log(queue.dequeue() + "是最后的胜利者");
}

let names = ["feng", "gping", "ling", "qing", "zeng"];
hotPotato(names, 4);

// 最小优先队列的实现
function PriorityQueue() {
  let items = [];
  function QueueElement(element, priority) {
    this.element = element;
    this.priority = priority;
  }

  this.enqueue = function (element, priority) {
    let queueElement = new QueueElement(element, priority);
    let add = false;
    // items.forEach((item, index) => {
    //     if (queueElement.priority < item.priority) {
    //         items.splice(index, 0, queueElement);
    //         add = true;
    //         break;   // forEach 中不能使用break
    //     }
    // })
    for (let index = 0; index < items.length; index++) {
      if (queueElement.priority < items[index].priority) {
        items.splice(index, 0, queueElement);
        add = true;
        break;
      }
    }
    if (!add) {
      items.push(queueElement);
    }
  };
  this.print = function () {
    items.forEach((item, index) => {
      console.dir(item); // 使用 dir 可以输出对象
      // console.dir(`item: ${item},index: ${index}`);
    });
  };
}

let queue = new PriorityQueue();
queue.enqueue(1, 2);
queue.print();
queue.enqueue(2, 1);
queue.print();
queue.enqueue(3, 4);
queue.print();