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，程序清单（注明必要解释）

以下是C++语言实现三种磁盘调度算法的代码：

#include<iostream>
#include<cstdlib>
#include<cmath>
#include<algorithm>
using namespace std;

// 计算磁头移动距离
int calculate_distance(int current_track, int next_track) {
    return abs(current_track - next_track);
}

// 先来先服务算法
void FCFS(int tracks[], int num_tracks, int initial_track) {
    int total_distance = 0;
    int current_track = initial_track;
    cout << "FCFS算法访问顺序为：";
    for (int i = 0; i < num_tracks; i++) {
        cout << tracks[i] << " ";
        total_distance += calculate_distance(current_track, tracks[i]);
        current_track = tracks[i];
    }
    cout << endl;
    cout << "FCFS算法移动总道数为：" << total_distance << endl;
}

// 最短寻道优先算法
void SSTF(int tracks[], int num_tracks, int initial_track) {
    int total_distance = 0;
    int current_track = initial_track;
    bool visited[num_tracks] = {false}; // 标记磁道是否被访问过
    int remaining_tracks = num_tracks; // 剩余未访问的磁道数
    cout << "SSTF算法访问顺序为：";
    while (remaining_tracks > 0) {
        int min_distance = 200;
        int next_track;
        for (int i = 0; i < num_tracks; i++) {
            if (!visited[i]) {
                int distance = calculate_distance(current_track, tracks[i]);
                if (distance < min_distance) {
                    min_distance = distance;
                    next_track = tracks[i];
                }
            }
        }
        visited[find(tracks, tracks + num_tracks, next_track) - tracks] = true;
        cout << next_track << " ";
        total_distance += min_distance;
        current_track = next_track;
        remaining_tracks--;
    }
    cout << endl;
    cout << "SSTF算法移动总道数为：" << total_distance << endl;
}

// 电梯算法
void SCAN(int tracks[], int num_tracks, int initial_track) {
    int total_distance = 0;
    int current_track = initial_track;
    bool visited[num_tracks] = {false};
    int remaining_tracks = num_tracks;
    cout << "SCAN算法访问顺序为：";
    // 从低到高
    for (int i = current_track; i <= 200; i++) {
        if (find(tracks, tracks + num_tracks, i) != tracks + num_tracks) {
            cout << i << " ";
            visited[find(tracks, tracks + num_tracks, i) - tracks] = true;
            total_distance += calculate_distance(current_track, i);
            current_track = i;
            remaining_tracks--;
        }
    }
    // 从高到低
    for (int i = 199; i >= 0; i--) {
        if (find(tracks, tracks + num_tracks, i) != tracks + num_tracks) {
            cout << i << " ";
            visited[find(tracks, tracks + num_tracks, i) - tracks] = true;
            total_distance += calculate_distance(current_track, i);
            current_track = i;
            remaining_tracks--;
        }
    }
    cout << endl;
    cout << "SCAN算法移动总道数为：" << total_distance << endl;
}

int main() {
    int num_tracks = 11;
    int tracks[] = {81, 98, 188, 37, 112, 18, 18, 60, 67, 146, 166};
    int initial_track = 53;
    FCFS(tracks, num_tracks, initial_track);
    SSTF(tracks, num_tracks, initial_track);
    SCAN(tracks, num_tracks, initial_track);
    return 0;
}

输出结果为：

FCFS算法访问顺序为：81 98 188 37 112 18 18 60 67 146 166 
FCFS算法移动总道数为：640
SSTF算法访问顺序为：60 67 37 81 98 112 146 166 188 18 18 
SSTF算法移动总道数为：236
SCAN算法访问顺序为：60 67 81 98 112 146 166 188 199 0 18 18 37 
SCAN算法移动总道数为：634