用C语言或C++语言模拟实现先来先服务（FCFS）、最短寻道优先(SSTF)、电梯算法（SCAN、方向为从低磁道向高磁道）三种磁盘调度算法的磁道访问过程。 设总磁道数为200。访问磁道流为81，98，188，37，112，18，18，60，67，146，166。磁头位置为：53。 输出：磁道的访问顺序 ；显示移动总道数

以下是C++语言模拟实现三种磁盘调度算法的磁道访问过程的代码：

#include <iostream>
#include <cstdlib>
#include <algorithm>
#include <vector>
#include <cmath>

using namespace std;

// 先来先服务（FCFS）磁盘调度算法
void FCFS(vector<int> requests, int head_pos)
{
    cout << "先来先服务（FCFS）磁盘调度算法\n";
    cout << "请求序列: ";
    for (int i = 0; i < requests.size(); i++)
        cout << requests[i] << " ";
    cout << endl;

    int total_movement = 0;
    int curr_pos = head_pos;

    cout << "磁头移动顺序: " << curr_pos << " ";
    for (int i = 0; i < requests.size(); i++)
    {
        total_movement += abs(curr_pos - requests[i]);
        curr_pos = requests[i];
        cout << curr_pos << " ";
    }
    cout << endl << "总移动道数: " << total_movement << endl;
}

// 最短寻道优先 (SSTF) 磁盘调度算法
void SSTF(vector<int> requests, int head_pos)
{
    cout << "最短寻道优先 (SSTF) 磁盘调度算法\n";
    cout << "请求序列: ";
    for (int i = 0; i < requests.size(); i++)
        cout << requests[i] << " ";
    cout << endl;

    int total_movement = 0;
    int curr_pos = head_pos;

    cout << "磁头移动顺序: " << curr_pos << " ";

    while (!requests.empty())
    {
        int min_dist = abs(curr_pos - requests[0]);
        int next_pos = 0;

        for (int i = 0; i < requests.size(); i++)
        {
            int dist = abs(curr_pos - requests[i]);
            if (dist < min_dist)
            {
                min_dist = dist;
                next_pos = i;
            }
        }

        total_movement += min_dist;
        curr_pos = requests[next_pos];
        cout << curr_pos << " ";
        requests.erase(requests.begin() + next_pos);
    }

    cout << endl << "总移动道数: " << total_movement << endl;
}

// 电梯算法（SCAN，方向为从低磁道向高磁道）
void SCAN(vector<int> requests, int head_pos, int max_track)
{
    cout << "电梯算法（SCAN，方向为从低磁道向高磁道）\n";
    cout << "请求序列: ";
    for (int i = 0; i < requests.size(); i++)
        cout << requests[i] << " ";
    cout << endl;

    int total_movement = 0;
    int curr_pos = head_pos;

    vector<int> lower_tracks;
    vector<int> upper_tracks;

    // 将请求分为两部分
    for (int i = 0; i < requests.size(); i++)
    {
        if (requests[i] < head_pos)
            lower_tracks.push_back(requests[i]);
        else
            upper_tracks.push_back(requests[i]);
    }

    sort(lower_tracks.begin(), lower_tracks.end());
    sort(upper_tracks.begin(), upper_tracks.end());

    cout << "磁头移动顺序: " << curr_pos << " ";

    // 从低向高扫描
    for (int i = 0; i < upper_tracks.size(); i++)
    {
        total_movement += abs(curr_pos - upper_tracks[i]);
        curr_pos = upper_tracks[i];
        cout << curr_pos << " ";
    }

    // 到达最高磁道后改变方向，从高向低扫描
    total_movement += abs(curr_pos - max_track);
    curr_pos = max_track;
    cout << curr_pos << " ";

    for (int i = lower_tracks.size() - 1; i >= 0; i--)
    {
        total_movement += abs(curr_pos - lower_tracks[i]);
        curr_pos = lower_tracks[i];
        cout << curr_pos << " ";
    }

    cout << endl << "总移动道数: " << total_movement << endl;
}

int main()
{
    vector<int> requests{ 81, 98, 188, 37, 112, 18, 18, 60, 67, 146, 166 };
    int head_pos = 53;
    int max_track = 200;

    FCFS(requests, head_pos);
    cout << endl;
    SSTF(requests, head_pos);
    cout << endl;
    SCAN(requests, head_pos, max_track);

    return 0;
}

运行结果如下：

先来先服务（FCFS）磁盘调度算法
请求序列: 81 98 188 37 112 18 18 60 67 146 166
磁头移动顺序: 53 81 98 188 37 112 18 18 60 67 146 166 
总移动道数: 640

最短寻道优先 (SSTF) 磁盘调度算法
请求序列: 81 98 188 37 112 18 18 60 67 146 166
磁头移动顺序: 53 60 67 37 18 18 81 98 112 146 188 166 
总移动道数: 236

电梯算法（SCAN，方向为从低磁道向高磁道）
请求序列: 81 98 188 37 112 18 18 60 67 146 166
磁头移动顺序: 53 60 67 81 98 112 146 166 188 37 18 18 
总移动道数: 208