DSAndOS/DSBookCode/BookCode/Two/2.1-2.5/2.1-2.5.cpp

#include<iostream>
#include<fstream>
#include<string>
#include<iomanip>

using namespace std;
#define OK 1
#define ERROR 0
#define OVERFLOW -2
typedef int Status; //Status 是函数返回值类型，其值是函数结果状态代码。
typedef int ElemType; //ElemType 为可定义的数据类型，此设为int类型

#define MAXSIZE 100            //顺序表可能达到的最大长度
struct Book {
    string id;//ISBN
    string name;//书名
    double price;//定价
};
typedef struct {
    Book *elem; //存储空间的基地址
    int length; //当前长度
} SqList;

Status InitList_Sq(SqList &L) { //算法2.1 顺序表的初始化
    //构造一个空的顺序表L
    L.elem = new Book[MAXSIZE]; //为顺序表分配一个大小为MAXSIZE的数组空间
    if (!L.elem)
        exit(OVERFLOW); //存储分配失败退出
    L.length = 0; //空表长度为0
    return OK;
}

Status GetElem(SqList L, int i, Book &e) {//算法2.2　顺序表的取值
    if (i < 1 || i > L.length)
        return ERROR; //判断i值是否合理，若不合理，返回ERROR
    e = L.elem[i - 1]; //elem[i-1]单元存储第i个数据元素
    return OK;
}

int LocateElem_Sq(SqList L, double e) { //算法2.3 顺序表的查找
    //顺序表的查找
    for (int i = 0; i < L.length; i++)
        if (L.elem[i].price == e)
            return i + 1;//查找成功，返回序号i+1
    return 0;//查找失败，返回0
}

Status ListInsert_Sq(SqList &L, int i, Book e) { //算法2.4 顺序表的插入
    //在顺序表L中第i个位置之前插入新的元素e
    //i值的合法范围是1<=i<=L.length+1
    if ((i < 1) || (i > L.length + 1))
        return ERROR; //i值不合法
    if (L.length == MAXSIZE)
        return ERROR; //当前存储空间已满
    for (int j = L.length - 1; j >= i - 1; j--)
        L.elem[j + 1] = L.elem[j]; //插入位置及之后的元素后移
    L.elem[i - 1] = e; //将新元素e放入第i个位置
    ++L.length; //表长增1
    return OK;
}

Status ListDelete_Sq(SqList &L, int i) { //算法2.5 顺序表的删除
    //在顺序表L中删除第i个元素，并用e返回其值
    //i值的合法范围是1<=i<=L.length
    if ((i < 1) || (i > L.length))
        return ERROR; //i值不合法
    for (int j = i; j <= L.length; j++)
        L.elem[j - 1] = L.elem[j]; //被删除元素之后的元素前移
    --L.length; //表长减1
    return OK;
}

int main() {
    SqList L;
    int i = 0, temp, a, c, choose;
    double price;
    Book e;
    string head_1, head_2, head_3;
    cout << "1. 建立\n";
    cout << "2. 输入\n";
    cout << "3. 取值\n";
    cout << "4. 查找\n";
    cout << "5. 插入\n";
    cout << "6. 删除\n";
    cout << "7. 输出\n";
    cout << "0. 退出\n\n";

    choose = -1;
    while (choose != 0) {
        cout << "请选择:";
        cin >> choose;
        switch (choose) {
            case 1://创建顺序表
                if (InitList_Sq(L))
                    cout << "成功建立顺序表\n\n";
                else
                    cout << "顺序表建立失败\n\n";
                break;
            case 2: {//顺序表信息输入
                i = 0;
                L.elem = new Book[MAXSIZE];
                if (!L.elem)
                    exit(OVERFLOW);
                L.length = 0;
                fstream file;
                file.open("book.txt");
                if (!file) {
                    cout << "错误！未找到文件！" << endl;
                    exit(ERROR);
                }
                file >> head_1 >> head_2 >> head_3;
                while (!file.eof()) {
                    file >> L.elem[i].id >> L.elem[i].name >> L.elem[i].price;
                    i++;
                }
                cout << "输入 book.txt 信息完毕\n\n";
                L.length = i;
                file.close();
            }
                break;
            case 3://顺序表的取值
                cout << "请输入一个位置用来取值：\n";
                cin >> i;
                temp = GetElem(L, i, e);
                if (temp != 0) {
                    cout << "查找成功\n";
                    cout << "第" << i << "本图书的信息是：\n";
                    cout << left << setw(15) << e.id << "\t" << left << setw(50)
                         << e.name << "\t" << left << setw(5) << e.price << endl
                         << endl;
                } else
                    cout << "查找失败！位置超出范围\n\n";
                break;
            case 4: //顺序表的查找
                cout << "请输入所要查找价格:";
                cin >> price;
                temp = LocateElem_Sq(L, price);
                if (temp != 0) {
                    cout << "查找成功\n";
                    cout << "该价格对应的书名为：" << L.elem[temp - 1].name << endl << endl;
                } else
                    cout << "查找失败！没有这个价格对应的书籍\n\n";
                break;
            case 5: //顺序表的插入
                cout << "请输入插入的位置和书本信息，包括：编号 书名 价格（用空格隔开）:";
                cin >> a;
                cin >> e.id >> e.name >> e.price; //输入a和b，a代表插入的位置，b代表插入的数值（书本信息）
                if (ListInsert_Sq(L, a, e))
                    cout << "插入成功.\n\n";
                else
                    cout << "插入失败.\n\n";
                break;
            case 6: //顺序表的删除
                cout << "请输入所要删除的书籍的位置:";
                cin >> c;
                if (ListDelete_Sq(L, c))
                    cout << "删除成功.\n\n";
                else
                    cout << "删除失败.\n\n";
                break;
            case 7: //顺序表的输出
                cout << "当前图书系统信息（顺序表）读出:\n";
                for (i = 0; i < L.length; i++)
                    cout << left << setw(15) << L.elem[i].id << "\t" << left
                         << setw(50) << L.elem[i].name << "\t" << left
                         << setw(5) << L.elem[i].price << endl;
                cout << endl;
                break;
        }
    }
    return 0;
}