js 队列 先进先出

队列

		function Queue() {
			// var items = []
			window.items = [] // 方便调试
			this.enqueue = function (e) {
				items.push(e)
			}

			this.dequeue = function (e) {
				return items.shift()
			}

			this.front = function (e) {
				return items[0]
			}

			this.isEmpty = function (e) {
				return items.length == 0
			}

			this.size = function (e) {
				return items.length
			}

			this.clear = function (e) {
				items = []
			}

			this.print = function (e) {
				console.log(items.toString())
			}
		}

根据优先级插入元素

	function PriorityQueue(){
			var items = []
			function QueueE(e, priority){
				this.e = e
				this.priority = priority
			}

			this.enqueue = function(e, priority){

				let queueE = new QueueE(e, priority)

				if(this.isEmpty()){
					items.push(queueE)
				}

				for(let i = 0;i<items.length;i++){
					let isAdd = false
					if(queueE.priority < items[i].priority){
						items.splice(i,0,queueE)
						isAdd = true
					}
					if(!isAdd){
						items.push(queueE)
					}
				}
			}	
		}