优先级算法写进程调度实验代码

在编写进程调度的优先级算法实验代码时，通常会涉及到操作系统原理中的抢占式调度，比如先来先服务（FCFS）、短任务优先（SJF）、最高优先级优先（HPF）等策略。这里以Python为例，给出一个简单的优先级队列调度示例：

import heapq

class Process:
    def __init__(self, pid, burst_time, priority):
        self.pid = pid
        self.burst_time = burst_time
        self.priority = priority

# 先来先服务调度
def fcfs(processes):
    processes.sort(key=lambda p: p.pid)  # 按pid排序
    result = []
    for process in processes:
        result.append(process)
        if not result[-1].burst_time:  # 如果进程结束，移除并继续
            result.pop()
    return result

# 最高优先级优先调度
def hpf(processes):
    heap = [(p.priority, p) for p in processes]  # 使用堆结构存储，优先级最高者位于堆顶
    heapq.heapify(heap)
    result = []
    while heap:
        _, process = heapq.heappop(heap)
        result.append(process)
        if not process.burst_time:  # 同理，进程结束后从堆中移除
            continue
        else:
            heapq.heappush(heap, (process.priority, Process(process.pid, process.burst_time - 1, process.priority)))  # 更新剩余时间后放回堆
    return result

# 示例过程列表
process_list = [
    Process(1, 8, 3),
    Process(2, 4, 5),
    Process(3, 6, 2)
]

# 调度并打印结果
print("FCFS:", fcfs(process_list))
print("HPF:", hpf(process_list))