Question

我有这段代码，提示用户在虚拟图书馆中输入书名，作者和ISBN。该代码将数据存储在链接列表中，这是我第一次使用链接列表。用户可以将一本书放入列表1或列表2中。然后，该用户应该能够比较两个列表中的哪些书籍通过输入ISBN。每当我尝试比较列表时，它只是空白。您能提供的任何帮助都将非常重要，谢谢！

我确保变量的所有名称都一致。至于排除实际链接列表是否有问题的疑难解答，老实说，我不知道。

#include <iostream>
#include<string>
using namespace std;

class linkList
{private:
     struct node
    {string title;
    string author;
    string ISBN;
    node *next; };

    node *head= NULL;

public: 
linkList(){};
void printList();
void addBook();
void compareList(linkList a);
bool isInListISBN(string ISBN);
};


void displayMenu();

int main()
{
    linkList book1;
    linkList book2;
    char selection;
    string ISBN;

    bool running=true;
    while (running)
    { displayMenu();
    cin>> selection;

    switch(selection)
    {case '1': book1.addBook();
        break;

    case '2': book2.addBook();
        break;

    case '3':
        cout<<"Please enter ISBN to check if the book is in the list"<<endl;
    cin>>ISBN;

    if(book1.isInListISBN(ISBN))
    {cout<<"ISBN "<<ISBN<< " is in book1"<<endl;}

    if (book2.isInListISBN(ISBN))
    {cout<<"ISBN "<<ISBN<< " is in book2"<<endl;}

    if (!book1.isInListISBN(ISBN) && !book2.isInListISBN(ISBN))
    {cout<< "ISBN "<<ISBN<<" could not be found, please verify entry is correct."<<endl;}
        break;


case '4':
    cout<<"book 1 : "<<endl;
    book1.printList();
    cout<<"book 2 : "<<endl;
    book2.printList();
        break;

case '5':
    book1.compareList(book2);
        break;

case '6':
    cout<<"Thank you for visiting the virtual library, please come again. "<<endl;
    running= false;
        break;


    }
    }
 }
    void displayMenu()
  {cout<<"Welcome to the virtual library. Select an option from the menu below."<<endl;
 cout<<"--------------------------------------------------------------------"<<endl;
 cout<<"1. Enter a book into list 1 "<<endl;
 cout<<"2. Enter a book into list 2 "<<endl;
 cout<<"3. Search for a book by ISBN "<<endl;
 cout<<"4. Print all books in lists"<<endl;
 cout<<"5. Compare lists "<<endl;
 cout<<"6. Exit virtual library"<<endl; };

 void linkList :: addBook()
 {string title;
 string author;
 string ISBN;

 cin.ignore();
 cout<<"Please enter title of book"<<endl;
 getline(cin, title);
 cout<<"Please enter author of book"<<endl;
 getline(cin, author);
 cout<<"Please enter ISBN"<<endl;
 getline(cin, ISBN);


 node *n= new node;
 node *c= head;

 n->title= title;
 n->author= author;
 n->ISBN= ISBN;
 n-> next= NULL;

 //if there is no head node, n is assigned the head node
 if (head== NULL)
 {head= n;}

 else
 {while (c-> next != NULL)
 {c= c-> next;}
 c-> next = n;}
 }

bool linkList :: isInListISBN(string ISBN)
{node *c= head;
while (c !=NULL);
{if (ISBN.compare(c->ISBN) ==0)
{return true;}
c= c-> next;
 }
 return false; 
}


void linkList :: printList()
{cout<<"The linked list contains the following books: \n\n"<<endl;
node *c= head;
while(c != NULL)
{cout<<"Title: "<<c->title<<endl;
 cout<<"Author: "<<c->author<<endl;
 cout<<"ISBN: "<<c->ISBN<<endl;

 c=c->next;
}
}

void linkList :: compareList(linkList a)
{bool matched = false;
node *c= head;
cout<<"Books in both lists: "<<endl;
while(c!=NULL)
{if (a.isInListISBN(c->ISBN))
{matched=true;
cout<< c->title<<endl;}
c=c->next;}

if(!matched)
{cout<<"None\n";}

}

我希望输出打印出具有相同ISBN的两个书名，而不是返回空白。

无法访问存储在链接列表中的数据

0 个答案: