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我面临的问题是我找不到计算开始时间的方法（在代码中称为startedAt），所以我能够计算周转时间和等待时间。我使用的逻辑如下：

  1. 我们首先复制突发时间“BurstTime”来存储剩余的突发时间remBurstTime。
  2. 根据优先级对进程进行排序（优先级越低表示优先级越高）
  3. 先到达的元素会一直运行，直到到达优先级较高的进程的到达时间，即我们从前一个进程的突发时间中减去后一个进程的到达时间。
  4. 运行 FCFS。

进程类

class ProcessInfo{
    public int ArrivalTime;
    public int BurstTime ;
    public int remBurstTime ;
    public int Priority ;
    public int TurnAroundTime;
    public int CompletionTime;
    public double WaitTime;

    
    public ProcessInfo(int ArrivalTime , int BurstTime , int priority){
        this.ArrivalTime = ArrivalTime ;
        this.BurstTime = BurstTime ;
        this.Priority = priority ;
    }


}

抢占式优先方法

public static void PriorityPreemptive(ProcessInfo[] process) {


        for (ProcessInfo processInfo : process) processInfo.remBurstTime = processInfo.BurstTime;

        for (int i = 0; i < process.length; i++) {

            for (int j = i + 1; j < process.length; ++j) {


                if (process[i].Priority > process[j].Priority) {
                    ProcessInfo temp = process[j];
                    process[j] = process[i];
                    process[i] = temp;
                    if (process[i].ArrivalTime < process[j].ArrivalTime) {
                        process[i].remBurstTime = process[i].BurstTime - process[j].ArrivalTime ;

                    }
                }


            }

        }

FCFS 类。

public static void FCFS(ProcessInfo[] process) {


        double TurnAroundTime = 0;
        double TotalTime = 0;
        int StartedAt = 0;

        if (process[0].ArrivalTime != StartedAt) {
            StartedAt = process[0].ArrivalTime;//initialize the startedAt time
        }

        //Now let's compute the avgTime and turnAroundTime of each process
        for (ProcessInfo processInfo : process) {

            processInfo.CompletionTime = StartedAt + processInfo.remBurstTime;//completion time (remBurst is the remaining burst time)
            StartedAt = processInfo.CompletionTime; // here is the issue

            processInfo.TurnAroundTime = processInfo.CompletionTime - processInfo.ArrivalTime;
            processInfo.WaitTime = processInfo.TurnAroundTime - processInfo.BurstTime;
            TotalTime += processInfo.WaitTime; // Calculate the total turnover time, and the value stored in avgTotalTime is the total turnover time
            TurnAroundTime += processInfo.TurnAroundTime; // Calculate the total weighted turnover time, and the value stored in avgPowerTime is the total weighted turnover time
            System.out.println("Started :\t " + StartedAt + "  Completion :\t " + processInfo.CompletionTime + "  TurnAround :\t "+ processInfo.TurnAroundTime + "  WaitTime :\t"+ processInfo.WaitTime);
        }

        double avgWaitingTime = TotalTime /  process.length;
        double avgTurnAroundTime =  TurnAroundTime /  process.length;



        System.out.println("The Average Waiting Time is :\t" + avgWaitingTime + "\nThe Average TurnAroundTime is :\t " + avgTurnAroundTime);
}

我用这个算法得到的结果非常接近，我只需要找到正确的方法来计算StartedAt以便其他时间（等待时间、周转时间）变得正确。

我希望你能帮我解决这个问题，在此先感谢。

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