文件+树，图书目录管理系统

【主要内容】
开发一个图书目录管理系统，作为图书馆系统的子系统。目录管理系统管理的对象是目录，要求是实现以下基本功能：
（1）对目录的增删查改功能
（2）对文件中保存的目录文件顺序输出
（3）输出树形目录

【数据结构】
树的存储结构，用.dat文件当作数据库。
关于文件的操作详见我的另一篇博文：

新手使用fwrite和fread一点小知识

在实现阶段，由于我读题不认真（西八），没看清楚需求。在存储和读取时树和数组混用了，造成了不少代码冗余，而我又懒得改。。各位大佬将就着看看吧。
代码：

#define _CRT_SECURE_NO_WARNINGS
#include
#include
#include
#include
using namespace std;
#define MAX_TREE_SIZE 100

typedef struct Catalog {    //目录结构类型
    char Key[20];          //编号
    char Caption[80];      //标题、类名
    char Parent[20];       //父类编号
}Catalog;

typedef struct CatalogTree {   //目录顺序存储结构类型
    Catalog Node[MAX_TREE_SIZE];
    int root;    //根结点位置
    int num;     //最后一个结点的数组编号
}CatalogTree;

void InitTree(CatalogTree &T)   //树的初始化
{
    for (int i = 0; i < MAX_TREE_SIZE; i++)
    {
        *T.Node[i].Caption = -1;
        *T.Node[i].Key = -1;
        *T.Node[i].Parent = -1;
    }
    T.root = 0;
    T.num = 0;
}
void Initdata()
{
    Catalog s[5] = {
        {"0","中国图书分类","-1"},
        {"A","马列主义","0"},
        {"B","哲学、宗教","0"},
        {"C","社会科学理论","0"},
        {"A1","论十大关系","A"} };
    FILE* fp = fopen("data.dat", "w+");
    if (fp == NULL)
    {
        exit(-1);
    }
    fwrite((void*)s, sizeof(s), 1, fp);
    fclose(fp);
}
void LoadTree(CatalogTree &T) {//从文件中读树从而构造树
    FILE* fp = fopen("catalog-目录管理数据源.dat", "rb");
    if (fp == NULL)
    {
        cout << "False" << endl;
        exit(-1);
    }
    for (int i = 0; i Key, T.Node->Caption, T.Node->Parent);
    fclose(fp);
}
void addCatalog(CatalogTree &T)     //增加目录
{
    Catalog *tmp = new Catalog;
    cout << "Key:";
    cin >> tmp->Key;
    getchar();
    cout << "Caption:";
    cin >> tmp->Caption;
    getchar();
    cout << "Parent:";
    cin >> tmp->Parent;
    getchar();
    T.Node[T.num++] = *tmp;
    Save(T);
}
int Search(CatalogTree& T)         //查找目录
{
    int b=0;
    Catalog* tmp = new Catalog;
    cout << "输入要查找的目录的编号：" << "n";
    cout << "Key:";
    cin >> tmp->Key;
    getchar();
    for (int i = 0; i < T.num; i++)
    {
        if (T.Node[i].Key==tmp->Key)
        {
            b = i;
            break;
        }
    }
    if (b == 0)
        cout << "要找的目录不存在" << endl;
    return b;
}

void DeleteCatalog(CatalogTree& T)    //删除结点
{
    int i = Search(T);
    for (i; i < T.num; i++)
    {
        T.Node[i] = T.Node[i + 1];
    }
    T.num--;
    Save(T);
}
void AlterCatalog(CatalogTree& T)
{
    int i = Search(T);
    cout << "输入要修改的内容:" << endl;
    cout << "Key:";
    cin >> T.Node[i].Key;
    getchar();
    cout << "Caption";
    cin >> T.Node[i].Caption;
    getchar();
    cout << "Parent:";
    cin >> T.Node[i].Parent;
    getchar();
    Save(T);
}

void PrintfCatalog(CatalogTree &T)   //顺序读出
{
    for (int i = 0; i < T.num; i++)
    {
        cout << T.Node[i].Key << T.Node[i].Caption << T.Node[i].Parent << endl;
   }
    cout << T.root << "n" << T.num << "n";
}
void CreatCatalogTree()
{

}
void PreOrder(CatalogTree& T, int k, int level)
{
    int m = 0;
    for (int i = 0; i < level; i++)
        cout << "       ";
    cout << "|--" << T.Node[k].Caption << "t" << T.Node[k].Key<<"n";
    for (int j = k + 1; j < T.num; j++)
    {
        if (!strcmp(T.Node[j].Parent, T.Node[k].Key))
        {
            m = 1;
            PreOrder(T, j, level + m);
        }
    }
}
void PrintCatalogTree(CatalogTree &T)
{
    int i = 0;
    int level = 1;
    PreOrder(T, i, level);
}

void menu(CatalogTree &T)
{
    cout << "        *************************************************         " << "n";
    cout << "                           分类管理菜单                           " << "n";
    cout << "        *************************************************         " << "n";
    cout << "*                          1.增加分类                            *" << "n";
    cout << "*                          2.输出分类                            *" << "n";
    cout << "*                          3.输出树形分类树                      *" << "n";
    cout << "*                          4.修改分类                            *" << "n";
    cout << "*                          5.删除分类                            *" << "n";
    cout << "*                          0.返回上级                            *" << "n";
    cout << "        *************************************************         " << "n";
    cout << "请输入你的选择！0-5：" << endl;
    int n;
    cin >> n;
    switch (n) {
    case 1:
        addCatalog(T);
        system("pause");
        break;
    case 2:
        PrintfCatalog(T);
        system("pause");
        break;
    case 3:
        PrintCatalogTree(T);
        system("pause");
        break;
    case 4:
        AlterCatalog(T);
        system("pause");
        break;
    case 5:
        DeleteCatalog(T);
        system("pause");
        break;
    case 0:
        system("pause");
        break;
    default:
        cout << "输入错误n";
        system("pause");
        break;
    }
}
int main()
{
    CatalogTree T;
    //Initdata(); 
    InitTree(T);
    LoadTree(T);
    while (1) {
        system("cls");
        menu(T);
        LoadTree(T);
    }
    return 0;
}

运行结果