图书管理系统

#include <iostream>
#include <fstream>
#include <iomanip>
#include <string>
#include <cstring>
#define ERROR 0
#define OK 1
#define MaxSize 1000000
using namespace std;
typedef int Status;
typedef struct
{
    string no;
    string name;
    int price;
}ElemType;
typedef struct
{
    ElemType *elem;
    int length;
}SqList;
SqList L;

Status InitList(SqList &L)//顺序表初始化 
{
    L.elem=new ElemType[MaxSize];
    if(!L.elem) return ERROR;
    
    L.length=0;
    return OK;
}

void Menu()//菜单选项 
{
    cout<<endl;
    cout<<"               1.从文件中读入数据到顺序表"<<endl;
    cout<<"               2.遍历顺序表"<<endl;
    cout<<"               3.查找"<<endl;
    cout<<"               4.插入"<<endl;
    cout<<"               5.删除"<<endl;
    cout<<"               6.修改"<<endl;
    cout<<"               7.排序:对图书价格升序排列"<<endl;
    cout<<"请选择功能选项:";
}

Status ReadFromFile(SqList &L,char *filename)//1.从文件读入数据到顺序表 
{
    ifstream infile(filename,ios::in);
    if(!infile) return ERROR;
    
    while(!infile.eof())
    {
        infile>>L.elem[L.length].no;
        infile>>L.elem[L.length].name;
        infile>>L.elem[L.length].price;
        L.length++;
    }
    infile.close();
    return OK;
}

Status ListPrint(SqList &L)//2.遍历顺序表输出 
{
    if(!L.length) return ERROR;
    
    cout<<left<<setw(18)<<"ISBN"<<left<<setw(24)<<"书名"<<"定价"<<endl;
    for(int i=0;i<=L.length-1;i++) cout<<left<<setw(18)<<L.elem[i].no<<left<<setw(24)<<L.elem[i].name<<left<<setw(24)<<L.elem[i].price<<endl;
    
    return OK;
}

int LocateElem(SqList &L,string s)//3.查找,返回元素位置序号 
{
    for(int i=0;i<=L.length-1;i++) if(L.elem[i].name==s || L.elem[i].no==s) return i+1;
    return 0;
}

Status ListInsert(SqList &L,int i,ElemType e)//4.插入元素 
{
    if(i<1 || i>L.length+1) return ERROR;
    if(L.length==MaxSize) return OK;
    for(int k=0;k<=L.length-1;k++) if(L.elem[k].no==e.no && L.elem[k].name==e.name && L.elem[k].price==e.price) return ERROR; 
    
    for(int j=L.length-1;j>=i-1;j--) L.elem[j+1]=L.elem[j];
    L.elem[i-1]=e;
    L.length++;
    return OK;
}

Status ListDelete(SqList &L,string s)//5.删除元素 
{
    int i=LocateElem(L,s);
    if(!i) return ERROR;
    
    i--;
    for(int j=i;j<=L.length-1;j++) L.elem[j]=L.elem[j+1];
    L.length--;
    return OK;
} 

Status ListChange(SqList &L,string s,ElemType e)//6.修改元素 
{
    int i=LocateElem(L,s);
    if(!i) return ERROR;
    
    i--;
    L.elem[i]=e;
    return OK;
}

int Partition(SqList &L,int left,int right)//快速排序,对图书价格升序排列
{
    ElemType Temp=L.elem[left];
    int temp=L.elem[left].price;
    while(left<right)
    {
        while(left<right && L.elem[right].price>=temp) right--;
        L.elem[left]=L.elem[right];
        while(left<right && L.elem[left].price<=temp) left++;
        L.elem[right]=L.elem[left];
    }
    L.elem[left]=Temp;

    return left;
}
void QSort(SqList &L,int left,int right)
{
    int pivotloc=0;
    if(left<right)
    {
        pivotloc=Partition(L,left,right);//移动并获取枢轴位置
        QSort(L,left,pivotloc-1);//递归左子序列
        QSort(L,pivotloc+1,right);//递归右子序列
    }
}

int main()
{
    int f=InitList(L);
    if(!f) 
    {
        cout<<"顺序表初始化失败！"<<endl;
        return 0;
    }
    else
    {
        cout<<"顺序表初始化成功！"<<endl; 
    }
    
    Menu();
    int choose;
    while(cin>>choose)
    {
        if(choose==1)
        {
            int ans=ReadFromFile(L,"afile.txt");
            if(!ans) cout<<"读入数据失败，文件不能被打开！"<<endl;
            else cout<<"读入数据成功！"<<endl; 
        }
        else if(choose==2)
        {
            int ans=ListPrint(L);
            if(!ans) cout<<"顺序表中没有元素！"<<endl;
        }
        else if(choose==3)
        {
            cout<<"请输入要查找的书名或其ISBN"<<endl;
            string s;
            cin>>s;
            
            int ans=LocateElem(L,s);
            if(!ans) cout<<"未找到该元素！"<<endl;
            else cout<<"该元素位置序号为"<<ans<<endl; 
        }
        else if(choose==4)
        {
            cout<<"请输入要插入的位置（1=<插入位置<=length+1）"<<endl;
            int pos;
            cin>>pos; 
            cout<<"请输入要插入的元素信息"<<endl;
            ElemType e;
            cin>>e.no>>e.name>>e.price;
            
            int ans=ListInsert(L,pos,e);
            if(!ans) cout<<"元素插入失败，请检查插入位置是否合法，元素是否已经存在，或空间是否已满！"<<endl;
            else cout<<"元素插入成功！"<<endl; 
        }
        else if(choose==5)
        {
            cout<<"请输入要删除书籍的ISBN"<<endl;
            string s;
            cin>>s;
            
            int ans=ListDelete(L,s);
            if(!ans) cout<<"元素删除失败，请检查该元素是否存在！"<<endl;
            else cout<<"元素删除成功！"<<endl;
        }
        else if(choose==6)
        {
            cout<<"请输入要修改书籍的ISBN"<<endl;
            string s;
            cin>>s;
            cout<<"请输入想要修改成的元素信息！"<<endl;
            ElemType e;
            cin>>e.no>>e.name>>e.price;
            
            int ans=ListChange(L,s,e);
            if(!ans) cout<<"元素修改失败，请检查该元素是否存在！"<<endl;
            else cout<<"元素修改成功！"<<endl;
        }
        else if(choose==7)
        {
            QSort(L,0,L.length-1);
            cout<<"元素按价格升序排序成功！"<<endl;

            int ans=ListPrint(L);
            if(!ans) cout<<"顺序表中没有元素！"<<endl;
        }
        else cout<<"输入错误，请重新输入！"<<endl;
        
        Menu();
    }
        
    return 0;
}

完。