进程调度代码及注释

以下是一个简单的进程调度代码及注释，使用了先来先服务（FCFS）调度算法：

#include <stdio.h>

// 定义进程结构体
struct process {
    int pid; // 进程ID
    int burst_time; // 进程需要的CPU时间
    int waiting_time; // 进程等待时间
    int turnaround_time; // 进程周转时间
};

int main() {
    int n; // 进程数
    float avg_waiting_time = 0, avg_turnaround_time = 0; // 平均等待时间和平均周转时间
    printf("Enter the number of processes: ");
    scanf("%d", &n);

    struct process processes[n]; // 定义进程数组

    // 输入每个进程的信息
    for(int i = 0; i < n; i++) {
        printf("Enter burst time for process %d: ", i+1);
        scanf("%d", &processes[i].burst_time);
        processes[i].pid = i+1;
    }

    // 计算每个进程的等待时间和周转时间
    processes[0].waiting_time = 0;
    processes[0].turnaround_time = processes[0].burst_time;
    for(int i = 1; i < n; i++) {
        processes[i].waiting_time = processes[i-1].waiting_time + processes[i-1].burst_time;
        processes[i].turnaround_time = processes[i].waiting_time + processes[i].burst_time;
    }

    // 计算平均等待时间和平均周转时间
    for(int i = 0; i < n; i++) {
        avg_waiting_time += processes[i].waiting_time;
        avg_turnaround_time += processes[i].turnaround_time;
    }
    avg_waiting_time /= n;
    avg_turnaround_time /= n;

    // 输出结果
    printf("\nProcess\tBurst Time\tWaiting Time\tTurnaround Time\n");
    for(int i = 0; i < n; i++) {
        printf("%d\t\t%d\t\t%d\t\t%d\n", processes[i].pid, processes[i].burst_time, processes[i].waiting_time, processes[i].turnaround_time);
    }
    printf("\nAverage Waiting Time: %.2f\n", avg_waiting_time);
    printf("Average Turnaround Time: %.2f\n", avg_turnaround_time);

    return 0;
}

注释见代码：