demo02/index.html

<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>demo02</title>
</head>
<body>
	<h1>demo02:队列的实现(普通队列,优先队列,循环队列)</h1>
	<h4>请打开调试工具(F12)</h4>
</body>
</html>
<script>

// -------------------【1】默认队列------------------------------

function Queue(){
	//使用数组来保存队列里的元素
	var items = [];
	//向队列尾部添加新项
	this.enqueue = function(element){
		items.push(element);
	};
	//移除队列第一项
	this.dequeue = function(){
		return items.shift();
	};
	//返回队列第一项
	this.front = function(){
		return items[0];
	};
	//判断队列是否为空
	this.isEmpty = function(){
		return items.length == 0;
	};
	//队列的元素个数
	this.size = function(){
		return items.length;
	};
	//清空队列
	this.clear = function(){
		items = [];
	};
	//输出全队列
	this.print = function(){
		console.log(items.toString());
	};
}
// ----------------使用默认队列---------------------------

// var queue = new Queue();
// console.log(queue.isEmpty()); // true
// queue.enqueue(5);
// console.log(queue.isEmpty()); //false
// queue.enqueue(8);
// queue.print();  //5,8
// queue.dequeue();
// queue.print();  //8


//-------------------【2】优先队列(最大优先级)----------------------------
function PriorityQueue(){
	//使用数组来保存队列里的元素
	var items = [];
	function QueueElement(element,priority){
		this.element = element;
		this.priority = priority;
	}
	//按照优先级 入队列
	this.enqueue = function(element,priority){
		var queueElement  = new QueueElement(element,priority);
		for(var i=0; i < items.length;i++)
		{
			if( queueElement.priority > items[i].priority)
			{
				if(i == 0)
				{
					items.unshift(queueElement);
				}
				else
				{
					items.splice(i,0,queueElement);
				}
				break;
			}
		}
		if(i == items.length)
		{
			items.push(queueElement);
		}
	};

	//其余同普通队列一样
	this.dequeue = function(){
		return items.shift();
	};
	this.front = function(){
		return items[0];
	};
	this.isEmpty = function(){
		return items.length == 0;
	};
	this.size = function(){
		return items.length;
	};
	this.clear = function(){
		items = [];
	};
	this.print = function(){
		console.log(JSON.stringify(items));
	};
}

//-------------------使用优先队列--------------------------
var priorityQueue = new PriorityQueue();
console.log(priorityQueue.isEmpty()); // true
priorityQueue.enqueue('wang',8);
priorityQueue.enqueue('li',7);
priorityQueue.enqueue('chen',9);
priorityQueue.enqueue('si',10);
priorityQueue.enqueue('qie',80);
priorityQueue.dequeue();
priorityQueue.print();
//[{"element":"si","priority":10},
//{"element":"chen","priority":9},
//{"element":"wang","priority":8},
//{"element":"li","priority":7}]


//------------------【3】循环队列------------------------------
//实现击鼓传花游戏,最后一个在场的为胜利者,num为击鼓次数
function hotPotato(nameList,num)
{
	var queue = new Queue();
	//参赛名字入队列
	for(let i = 0; i < nameList.length; i++)
	{
		queue.enqueue(nameList[i]);
	}
	var outName = '';
	while(queue.size > 1)
	{
		for(let i=0;i<num;i++)
		{
			//队列头变为队列为，形成循环队列
			queue.enqueue(queue.dequeue());
		}
		outName = queue.dequeue();
		console.log(outName+"被淘汰");
	}
	return queue.dequeue();
}
// var names = ['one','two','three','four','five'];
// console.log("胜利者是："+hotPotato(names,7));   //假定击鼓7次


</script>