JavaScript实现优先数调度算法（含交互页面）

本文链接：https://blog.youkuaiyun.com/weixin_50926010/article/details/124138597

因为怕被老师抽查问到，所以连夜把这个算法用javaScript写出来了，之所以用JavaScript写出来，还是因为其交互页面可以自己设计更美观，其次就是JavaScript写起来比较轻量把，对运行环境要求没有那么高，最重要一点就是每一行结尾可以不写分号（懒人狂喜）且JavaScript对数组和字符串的API使用起来比较方便，所以以后写算法应该都是用JavaScript了。

首先说一下思路：我既没有用到栈也没有用到链表，当时感觉用数组加原生js 就可以实现了，自始至终都是对数组和对象进行操作，首先输入一个数字决定运行的进程个数，然后动态创建输入框，输入进程的运行信息，把每个进程的信息放在对象中储存，然后用数组存储多个对象，定义一个全局的时间Time,有多少个进程就遍历多少次，遍历一遍将一个符合要求的进程的状态status由wait改为ready，之后遍历的时候通过filter筛选出status=="wait"的进行遍历既可，如果在一定时间内有多个进程可以被执行，并且createTime<Time,将这些进程push到数组newArr中，然后调用sortall(newArr)函数处理，最后结束alert("运行结束!")。

那么sortall函数如何实现呢?

有以下两种情况：

1，newArr.length!=0,然后筛选出最大的优先数的数组下标（这里默认最大的优先执行），修改status和Time,然后输出(Timfe)

 if (newArr.length != 0) {
                let Max = 0
                let Maxindex = 0
                newArr.forEach((item, index) => {
                    if (item.priority > Max) {
                        Max = item.priority;
                        Maxindex = index
                    }
                })
                arrall.forEach(item => {
                    if (item.name === newArr[Maxindex].name) {
                        item.status = "ready"
                        Time = parseInt(item.runTime) + parseInt(Time)
                    }
                })
                print_info(newArr, Maxindex, index)
            }

2，newArr.length==0，表示无一个进程createTime<Time，此时直接以Time作为加载线程的初始时间，修改status和Time,然后输出

{
                let Min = 99999
                let Minindex = 0
                let Max = 0
                let Maxindex = 0
                let someArr = []
                waitarrall.forEach((item, index) => {
                    if (parseInt(item.createTime) <= Min) {
                        Min = parseInt(item.createTime);
                        Minindex = index
                    }
                })
                waitarrall.forEach(item => {
                    if (parseInt(item.createTime) === Min) {
                        someArr.push(item)
                    }
                })
                someArr.forEach((item, index) => {
                    if (item.priority > Max) {
                        Max = item.priority;
                        Maxindex = index
                    }
                })
                arrall.forEach(item => {
                    if (item.name === someArr[Maxindex].name) {
                        item.status = "ready"
                        Time = parseInt(item.createTime) + parseInt(item.runTime)
                    }
                })
                print_info(someArr, Maxindex, index)
            }

print_info为输出的函数：

  function print_info(newArr, Maxindex, index) {
            statement = ""
            let sortArr = []
            newArr.forEach(item => {
                sortArr.push(item.priority)
            })
            let string = sortArr.sort().join(" ")
            statement = statement.concat("当前就绪进程:")
            newArr.forEach(item => {
                statement = statement.concat(item.name + " ")
            })
            statement = statement.concat("<br>")
            statement = statement.concat("当前就绪线程优先级:" + string)
            statement = statement.concat("<br>")
            statement = statement.concat("时间Time:" + Time + ",进程" + newArr[Maxindex].name + "完成")
            statement = statement.concat("<br>")
            statement = statement.concat("--------------")
            statement = statement.concat("<br>")
            result.children[index].innerHTML = statement



        }

基本的算法思想就是这些了，全部代码（涵html+css）如下：

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        * {
            margin: 0;
            padding: 0;
        }
        
        .content input {
            display: block;
            margin-top: 10px;
        }
        
        .button1 {
            display: none;
        }
        
        .main_content {
            width: 1200px;
            margin: 100px auto;
            display: flex;
        }
        
        .main {
            width: 500px;
            padding: 10px;
            font-size: 14px;
            font-weight: 600;
        }
        
        .result {
            width: 400px;
            margin-left: 150px;
            font-size: 14px;
            font-weight: 600;
        }
        
        .result div {
            display: none;
            border: 2px solid #ccc;
            margin-top: 20px;
        }
        
        .result div:nth-child(1) {
            margin-top: 0;
        }
    </style>
</head>

<body>
    <div class="main_content">
        <div class="main">
            <div>
                输入进程的数量<input type="text" class="inputnum">
                <button class="button">确定</button>
            </div>
            <div class="title">输入进程的信息(标识符、创建时间、运行时间、优先级数)以空格分隔</div>
            <div class="content"></div>
            <button class="button1">开始执行</button>

        </div>
        <div class="result">
        </div>


    </div>
    <script>
        var input = document.querySelector(".inputnum")
        var btn = document.querySelector(".button")
        var btn1 = document.querySelector(".button1")
        var content = document.querySelector(".content")
        var result = document.querySelector(".result")
        var arrall = []
        var waitarrall = []
        var Time = 0
        var newArr
        var statement
        btn.addEventListener("click", function() {
            btn1.style.display = "block"
            content.innerHTML = ""
            var value = input.value
                //动态生成input
            for (let i = 0; i < value; i++) {
                var input3 = document.createElement("input")
                var div = document.createElement("div")
                content.appendChild(input3)
                result.appendChild(div)
            }
            inputArr = document.querySelector('.content').children
            for (let i = 0; i < inputArr.length; i++) {
                inputArr[i].addEventListener("blur", function() {
                    var arr = this.value.trim().split(" ")
                    var obj = {}
                    obj.name = arr[0]
                    obj.createTime = arr[1]
                    obj.runTime = arr[2]
                    obj.priority = arr[3]
                    obj.status = "wait"
                    arrall.push(obj)
                })

            }

        })

        function print_info(newArr, Maxindex, index) {
            statement = ""
            let sortArr = []
            newArr.forEach(item => {
                sortArr.push(item.priority)
            })
            let string = sortArr.sort().join(" ")
            statement = statement.concat("当前就绪进程:")
            newArr.forEach(item => {
                statement = statement.concat(item.name + " ")
            })
            statement = statement.concat("<br>")
            statement = statement.concat("当前就绪线程优先级:" + string)
            statement = statement.concat("<br>")
            statement = statement.concat("时间Time:" + Time + ",进程" + newArr[Maxindex].name + "完成")
            statement = statement.concat("<br>")
            statement = statement.concat("--------------")
            statement = statement.concat("<br>")
            result.children[index].innerHTML = statement



        }

        function sortall(newArr, index) {
            if (newArr.length != 0) {
                let Max = 0
                let Maxindex = 0
                newArr.forEach((item, index) => {
                    if (item.priority > Max) {
                        Max = item.priority;
                        Maxindex = index
                    }
                })
                arrall.forEach(item => {
                    if (item.name === newArr[Maxindex].name) {
                        item.status = "ready"
                        Time = parseInt(item.runTime) + parseInt(Time)
                    }
                })
                print_info(newArr, Maxindex, index)
            } else {
                let Min = 99999
                let Minindex = 0
                let Max = 0
                let Maxindex = 0
                let someArr = []
                waitarrall.forEach((item, index) => {
                    if (parseInt(item.createTime) <= Min) {
                        Min = parseInt(item.createTime);
                        Minindex = index
                    }
                })
                waitarrall.forEach(item => {
                    if (parseInt(item.createTime) === Min) {
                        someArr.push(item)
                    }
                })
                someArr.forEach((item, index) => {
                    if (item.priority > Max) {
                        Max = item.priority;
                        Maxindex = index
                    }
                })
                arrall.forEach(item => {
                    if (item.name === someArr[Maxindex].name) {
                        item.status = "ready"
                        Time = parseInt(item.createTime) + parseInt(item.runTime)
                    }
                })
                print_info(someArr, Maxindex, index)
            }


        }

        function handle() {
            for (let i = 0; i < result.children.length; i++) {
                result.children[i].style.display = "block"

            }
            for (let i = 0; i < inputArr.length; i++) {
                newArr = []
                waitarrall = arrall.filter(item => item.status === "wait")
                waitarrall.forEach((item, index) => {
                    if (parseInt(item.createTime) <= Time) {
                        newArr.push(item)
                    }
                })
                sortall(newArr, i)
            }
            alert("计算结束!")

        }
        btn1.addEventListener("click", handle)
    </script>
</body>

</html>