9.11作业 - 技术栈

cpp 复制代码

#include <iostream>
#include <cstring>
#include <cstdlib>

using namespace std;

class MyString
{
    friend MyString &operator+=(MyString &L,const MyString &R);
    friend ostream &operator<<(ostream &cout,const MyString &p);
    friend istream &operator>>(istream &cin,MyString &p);
    friend bool operator==(MyString &L,const MyString &R);
private:
    char* arr;
    char* brr;
    size_t arr_len;
    size_t brr_len;

    void copyString(char* &dest,const char* src,size_t &len)
    {
        if(src && src[0] != '\0')
        {
            len = strlen(src);
            dest = new char[len + 1];
            strcpy(dest,src);
        }
        else
        {
            dest = nullptr;
            len = 0;
        }
    }

    void freeString(char* &str)
    {
        if(str)
        {
            delete[] str;
            str = nullptr;
        }
    }

public:
    MyString():arr(nullptr),brr(nullptr),arr_len(0),brr_len(0){}
    MyString(const char* a,const char* b)
    {
        copyString(arr,a,arr_len);
        copyString(brr,b,brr_len);
    }
    MyString(const MyString &other)
    {
        copyString(arr,other.arr,arr_len);
        copyString(brr,other.brr,brr_len);
    }

    ~MyString()
    {
        freeString(arr);
        freeString(brr);
    }

    MyString &operator=(const MyString &other)
    {
        if(this != &other)
        {
            freeString(arr);
            freeString(brr);
            copyString(arr,other.arr,arr_len);
            copyString(brr,other.brr,brr_len);
        }
        return *this;
    }

    void size() const
    {
        cout << "First length:" << arr_len << endl;
        cout << "Second length:" << brr_len << endl;
    }

    void cmp() const
    {
        if(strcmp(arr,brr) == 0)
        {
            cout << "equal" << endl;
        }
        else
        {
            cout << "not equal" << endl;
        }
    }

    void show() const
    {
        cout << "First:" << arr << endl;
        cout << "Second:" << brr << endl;
    }
    void cat()
    {
        if(!brr) return;

        size_t new_len = arr_len + brr_len;
        char* new_arr = new char[new_len + 1];
        new_arr[0] = '\0';

        if(arr)
        {
            strcpy(new_arr,arr);
        }
        if(brr)
        {
            strcat(new_arr,brr);
        }

        freeString(arr);
        arr = new_arr;
        arr_len = new_len;

        cout << "new:" << arr << endl;
        cout << "new length:" << arr_len << endl;
    }
};

MyString &operator+=(MyString &L,const MyString &R)
{
    if(R.arr)
    {
        size_t new_len = L.arr_len + strlen(R.arr);
        char* new_arr = new char[new_len + 1];
        new_arr[0] = '\0';
        if(L.arr)
        {
            strcpy(new_arr,L.arr);
        }
        strcat(new_arr,R.arr);

        L.freeString(L.arr);
        L.arr = new_arr;
        L.arr_len = new_len;
    }
    return L;
}

ostream &operator<<(ostream &cout,const MyString &p)
{
    cout << "First:" << p.arr << " Second:" << p.brr << endl;
    return cout;
}

istream &operator>>(istream &cin,MyString &p)
{
    p.freeString(p.arr);
    p.freeString(p.brr);

    char buff1[256],buff2[256];

    cout << "input First:";
    cin >> buff1;
    cout << "input Second:";
    cin >> buff2;

    p.copyString(p.arr,buff1,p.arr_len);
    p.copyString(p.brr,buff2,p.brr_len);

    return cin;
}

bool operator==(MyString &L,const MyString &R)
{
    if(L.arr && R.brr)
    {
        return false;
    }
    return true;
}

int main()
{
    MyString a;
    cin >> a;
    cout << "============" << endl;
    a.show();
    a.size();
    a.cmp();
    a.cat();
    return 0;
}

cpp 复制代码

#include <iostream>
#include <vector>
#include <string>


using namespace std;

//图书类
class Book
{
private:
    string title;
    string author;
    int stock;

public:
    Book(string t,string a,int s):title(t),author(a),stock(s)
    {}

    //获取图书信息
    string getTitle() const
    {
        return title;
    }
    string getAuthor() const
    {
        return author;
    }
    int getStock() const
    {
        return stock;
    }

    //借书
    bool borrowBook()
    {
        if(stock > 0)
        {
            stock--;
            return true;
        }
        return false;
    }

    //还书
    void returnBook()
    {
        stock++;
    }

    //显示图书信息
    void display() const
    {
        cout << "书名: " << title << " 作者: " << author << " 库存: " << stock << endl;
    }
};

//图书管理系统类
class LibrarySystem
{
private:
    vector<Book> books;

public:
    //添加图书
    void addBook(string title,string author,int stock)
    {
        books.push_back(Book(title,author,stock));
        cout << "添加成功" << endl;
    }

    //借书
    void borrowBook(string title)
    {
        for(auto& book : books)
        {
            if(book.getTitle() == title)
            {
                if(book.borrowBook())
                {
                    cout << "借书成功" << endl;
                }
                else
                {
                    cout << "借书失败，库存不足" << endl;
                }
                return;
            }
        }
        cout << "未找到该图书" << endl;
    }

    //还书
    void returnBook(string title)
    {
        for(auto& book : books)
        {
            if(book.getTitle() == title)
            {
                book.returnBook();
                cout << "还书成功" << endl;
                return;
            }
        }
        cout << "未找到该图书" << endl;
    }

    //查询图书
    void searchBook(string keyword)
    {
        bool found = false;
        cout << "查询结果:" << endl;

        for (const auto& book : books)
        {
            string title = book.getTitle();
            string author = book.getAuthor();

            //检查书名是否包含关键字
            bool titleMatch = false;
            for(size_t i = 0;i <= title.length() - keyword.length();i++)
            {
                if(title.substr(i, keyword.length()) == keyword)
                {
                    titleMatch = true;
                    break;
                }
            }

            //检查作者是否包含关键字
            bool authorMatch = false;
            for(size_t i = 0;i <= author.length() - keyword.length();i++)
            {
                if (author.substr(i,keyword.length()) == keyword)
                {
                    authorMatch = true;
                    break;
                }
            }

            if(titleMatch || authorMatch)
            {
                book.display();
                found = true;
            }
        }

        if(!found)
        {
            cout << "未找到相关图书!" << endl;
        }
    }

    //显示所有图书
    void displayAllBooks()
    {
        if(books.empty())
        {
            cout << "图书馆暂无图书" << endl;
            return;
        }

        cout << "所有图书信息:" << endl;
        for(const auto& book : books)
        {
            book.display();
        }
    }
};

//显示菜单
void displayMenu()
{
    cout << "\n===== 图书管理系统 =====" << endl;
    cout << "1. 添加图书" << endl;
    cout << "2. 借书" << endl;
    cout << "3. 还书" << endl;
    cout << "4. 查询图书" << endl;
    cout << "5. 显示所有图书" << endl;
    cout << "0. 退出系统" << endl;
    cout << "请选择操作: ";
}

//清除
void clearInputBuffer()
{
    //读取并清除缓冲区中的所有字符，直到遇到换行符
    while (cin.get() != '\n')
    {
        continue;
    }
}

int main()
{
    LibrarySystem library;
    int choice;
    string title, author, keyword;
    int stock;

    do
    {
        displayMenu();
        cin >> choice;

        clearInputBuffer();

        switch (choice)
        {
            case 1:
                cout << "请输入书名: ";
                getline(cin,title);
                cout << "请输入作者: ";
                getline(cin,author);
                cout << "请输入库存数量: ";
                cin >> stock;
                clearInputBuffer();
                library.addBook(title,author,stock);
                break;
            case 2:
                cout << "请输入要借的书名: ";
                getline(cin,title);
                library.borrowBook(title);
                break;
            case 3:
                cout << "请输入要还的书名: ";
                getline(cin,title);
                library.returnBook(title);
                break;
            case 4:
                cout << "请输入书名或作者关键字: ";
                getline(cin,keyword);
                library.searchBook(keyword);
                break;
            case 5:
                library.displayAllBooks();
                break;
            case 0:
                cout << "感谢使用图书管理系统" << endl;
                break;
            default:
                cout << "无效的选择，请重新输入" << endl;
                cin.clear();
                clearInputBuffer();
        }
    }while(choice != 0);

    return 0;
}