text1/book.cpp

#include <iostream>
using namespace std;

#include "sqlist.h" // 顺序表

// 图书信息
struct Book {
    int id;        // 编号
    string title;  // 标题
    string author; // 作者
    float price;   // 价格
};

// 所有书的列表
SqList<Book> books;

int get_command();   // 读取命令
void DoAddBook();    // 添加图书
void DoFindBook();   // 查找图书
void DoDeleteBook(); // 删除图书
void DoPrintBook();  // 打印图书

int main()
{
    bool finish = false;

    InitList(books);

    while (!finish) {
        switch (get_command()) {
        case 1: // Add book
            DoAddBook();
            break;
        case 2: // Find book
            DoFindBook();
            break;
        case 3: // Delete book
            DoDeleteBook();
            break;
        case 4: // Print
            DoPrintBook();
            break;
        case 0: // Exit
            finish = true;
            break;
        default: // no command
            cout << "Error command." << endl;
        }
    }

    DestroyList(books);

    return 0;
}

// 读取命令
int get_command()
{
    int cmd;
    cout << "Commands: (1) Add, (2) Find, (3) Delete, (4) Print, (0) Exit\n";
    cout << "Enter your choice (0-4): ";
    cin >> cmd;
    return cmd;
}

// 输入一本书的信息
void read(Book& b)
{
    cout << "ID    : ";
    cin >> b.id;
    cin.ignore(1024, '\n'); // skip rest chars of the line
    cout << "TITLE : ";
    getline(cin, b.title);
    cout << "AUTHOR: ";
    getline(cin, b.author);
    cout << "PRICE : ";
    cin >> b.price;
}

// 打印一本书的信息
void print(const Book& b)
{
    cout << "Book { id: " << b.id << ","
         << " title:\"" << b.title << "\","
         << " author: \"" << b.author << "\","
         << " price: " << b.price << " }"
         << endl;
}

// 根据 id 查找图书
// 若找到，返回元素的位序，找不到时返回 0
int find(int id)
{
    
    for (int i = 1; i <= books.length; i++)
    {
        if (id == books.elem[i].id){
        return i;
        }
    }
    return 0; // not found
}

// 添加图书
void DoAddBook()
{
    Book e;
    read(e);
    books.elem[books.length + 1] = e;
    books.length++;
    print(e);
    cout << "Added" << endl;
}

// 查找图书
void DoFindBook()
{
    int id;
    cout << "Enter book ID: ";
    cin >> id;
    Book e;

    if (find(id) == 0)
        cout << "Not found" << endl;
    else
    {
        e = books.elem[find(id)];
        print(e);
        cout << "Found" << endl;
    }
}

// 删除图书
void DoDeleteBook()
{
    int id;
    cout << "Enter book ID: ";
    cin >> id;
    Book e;
    int c = find(id);
    if (find(id) == 0)
        cout << "Not found" << endl;
    else
    {
        e = books.elem[c];
        print(e);
        for (int i = c; i < books.length; i++)
        {
            books.elem[i] = books.elem[i + 1];
        }
        --books.length;
        cout << "Deleted" << endl;
    }
}

// 打印图书
void DoPrintBook()
{
    int flag = 0;
    for (int i = 0; i < books.length; i++)
    {
        Book e;
        e = books.elem[i + 1];
        print(e);
        flag++;
    }
    cout << "Total: ";
    cout << flag;
    cout << " books" << endl;
}