Linked list, how do I put this in a class? compiles but crashes

RLB31384 (15)
I coded this without putting it in a class and planned to do it at the end, it has been giving me a little trouble. Its a pretty long code, so any tips would be fine. I attempted to put the struct in the private section of a Library class.

It says in my book that the struct for making linked list is generally declared above the class template and in the class spec file. So I shouldnt store it in the private section? It seems like it would be better there to protect the information in the struct?

When I tried putting it in the private section, I changed line 26 to Library::node *temp, when trying to compile it says that it can't access private struct. Can someone explain to me the best way to put a linked list in the class, or should I just put it above the class like the book suggest. Thanks

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#include <algorithm>
#include <iostream>
#include <string>
#include <cctype>
#include <fstream>

using namespace std;

struct node
  {  string title; 
     string author;         
     string subject;     
	 node *nxt;
  };

node *start_ptr = NULL;
int option = 0;


void sortTitle()
{
	string titleOrder[50][3];
	int counter;
	int result = 0;
	string sort;
	node *temp;
	string tempArray[50];

    temp = start_ptr;
    cout << endl;
    if (temp == NULL)
		cout << "The list is empty!" << endl;
    else
	{ 
		// Load list of titles
		for (int i=0; temp != NULL; i++)
		{
			titleOrder[i][0] = temp->title;
			titleOrder[i][1] = temp->author;
			titleOrder[i][2] = temp->subject;
			temp = temp->nxt;
			counter = i + 1;
		}
	}
	//copy to tempArray
	for (int i=0; i < counter; i++)
	{
		tempArray[i] = titleOrder[i][0];
	}

	//tolower array for sort
	for (int i=0; i < counter; i++)
	{
		transform(titleOrder[i][0].begin(), titleOrder[i][0].end(), titleOrder[i][0].begin(),static_cast < int(*)(int) > (tolower));
	}

	//sort

	for (int i=0; i < counter; i++)
	{
		for (int ii=0; ii < counter-1; ii++)
		{
			result = titleOrder[ii][0].compare(titleOrder[ii+1][0]);
			if( result > 0 )
			{
				sort = titleOrder[ii][0];
				titleOrder[ii][0] = titleOrder[ii + 1][0];
				titleOrder[ii + 1][0] = sort;
				sort = tempArray[ii];
				tempArray[ii] = tempArray[ii + 1];
				tempArray[ii + 1] = sort;
				sort = titleOrder[ii][1];
				titleOrder[ii][1] = titleOrder[ii + 1][1];
				titleOrder[ii + 1][1] = sort;
				sort = titleOrder[ii][2];
				titleOrder[ii][2] = titleOrder[ii + 1][2];
				titleOrder[ii + 1][2] = sort;
			}
		}
	}
	for (int i=0; i < counter; i++)
	{
		titleOrder[i][0] = tempArray[i];
		cout << "Book #" << i+1 << endl;
		cout << "---------------------------------------" << endl;
		cout << "Title:   " << titleOrder[i][0] << endl;
		cout << "Author:  " << titleOrder[i][1] << endl;
		cout << "Subject: " << titleOrder[i][2] << endl << endl;
	}
}

void sortAuthor()
{
	string authorOrder[50][3];
	int counter;
	int result = 0;
	string sort;
	node *temp;
	string tempArray[50];

    temp = start_ptr;
    cout << endl;
    if (temp == NULL)
		cout << "The list is empty!" << endl;
    else
	{ 
		// Load list of titles
		for (int i=0; temp != NULL; i++)
		{
			authorOrder[i][0] = temp->author;
			authorOrder[i][1] = temp->title;
			authorOrder[i][2] = temp->subject;
			temp = temp->nxt;
			counter = i + 1;
		}
	}
	//copy to tempArray
	for (int i=0; i < counter; i++)
	{
		tempArray[i] = authorOrder[i][0];
	}

	//tolower array for sort
	for (int i=0; i < counter; i++)
	{
		transform(authorOrder[i][0].begin(), authorOrder[i][0].end(), authorOrder[i][0].begin(),static_cast < int(*)(int) > (tolower));
	}

	//sort

	for (int i=0; i < counter; i++)
	{
		for (int ii=0; ii < counter-1; ii++)
		{
			result = authorOrder[ii][0].compare(authorOrder[ii+1][0]);
			if( result > 0 )
			{
				sort = authorOrder[ii][0];
				authorOrder[ii][0] = authorOrder[ii + 1][0];
				authorOrder[ii + 1][0] = sort;
				sort = tempArray[ii];
				tempArray[ii] = tempArray[ii + 1];
				tempArray[ii + 1] = sort;
				sort = authorOrder[ii][1];
				authorOrder[ii][1] = authorOrder[ii + 1][1];
				authorOrder[ii + 1][1] = sort;
				sort = authorOrder[ii][2];
				authorOrder[ii][2] = authorOrder[ii + 1][2];
				authorOrder[ii + 1][2] = sort;
			}
		}
	}
	for (int i=0; i < counter; i++)
	{
		authorOrder[i][0] = tempArray[i];
		cout << "Book #" << i+1 << endl;
		cout << "---------------------------------------" << endl;
		cout << "Author:   " << authorOrder[i][0] << endl;
		cout << "Title:  " << authorOrder[i][1] << endl;
		cout << "Subject: " << authorOrder[i][2] << endl << endl;
	}
}

void sortSubject()
{
	string subjectOrder[50][3];
	int counter;
	int result = 0;
	string sort;
	node *temp;
	string tempArray[50];

    temp = start_ptr;
    cout << endl;
    if (temp == NULL)
		cout << "The list is empty!" << endl;
    else
	{ 
		// Load list of titles
		for (int i=0; temp != NULL; i++)
		{
			subjectOrder[i][0] = temp->subject;
			subjectOrder[i][1] = temp->title;
			subjectOrder[i][2] = temp->author;
			temp = temp->nxt;
			counter = i + 1;
		}
	}
	//copy to tempArray
	for (int i=0; i < counter; i++)
	{
		tempArray[i] = subjectOrder[i][0];
	}

	//tolower array for sort
	for (int i=0; i < counter; i++)
	{
		transform(subjectOrder[i][0].begin(), subjectOrder[i][0].end(), subjectOrder[i][0].begin(),static_cast < int(*)(int) > (tolower));
	}

	//sort

	for (int i=0; i < counter; i++)
	{
		for (int ii=0; ii < counter-1; ii++)
		{
			result = subjectOrder[ii][0].compare(subjectOrder[ii+1][0]);
			if( result > 0 )
			{
				sort = subjectOrder[ii][0];
				subjectOrder[ii][0] = subjectOrder[ii + 1][0];
				subjectOrder[ii + 1][0] = sort;
				sort = tempArray[ii];
				tempArray[ii] = tempArray[ii + 1];
				tempArray[ii + 1] = sort;
				sort = subjectOrder[ii][1];
				subjectOrder[ii][1] = subjectOrder[ii + 1][1];
				subjectOrder[ii + 1][1] = sort;
				sort = subjectOrder[ii][2];
				subjectOrder[ii][2] = subjectOrder[ii + 1][2];
				subjectOrder[ii + 1][2] = sort;
			}
		}
	}
	for (int i=0; i < counter; i++)
	{
		subjectOrder[i][0] = tempArray[i];
		cout << "Book #" << i+1 << endl;
		cout << "---------------------------------------" << endl;
		cout << "Subject:   " << subjectOrder[i][0] << endl;
		cout << "Title:  " << subjectOrder[i][1] << endl;
		cout << "Author: " << subjectOrder[i][2] << endl << endl;
	}
}
	
	 

void add_node_at_end()
  {  node *temp, *temp2;   // Temporary pointers

     // Reserve space for new node and fill it with data
     temp = new node;
	 cin.ignore();
     cout << "Please enter the title of the book: ";
	 getline(cin, temp->title);
     cout << "Please enter the author: ";
     getline(cin, temp->author);
     cout << "Please enter the subject: ";
     getline(cin, temp->subject);
     temp->nxt = NULL;

     // Set up link to this node
     if (start_ptr == NULL)
       { start_ptr = temp;
       }
     else
       { temp2 = start_ptr;
         // We know this is not NULL - list not empty!
         while (temp2->nxt != NULL)
           {  temp2 = temp2->nxt;
              // Move to next link in chain
           }
         temp2->nxt = temp;
       }
  }

void displayList()
{  
	int sortList = 0;
	node *temp;
     temp = start_ptr;
     cout << endl;
     if (temp == NULL)
       cout << "The list is empty!" << endl;
     else
	 {
		 cout << "Please select an option : " << endl;
		 cout << "0. Exit the list display." << endl;
	     cout << "1. Sort list by title." << endl;
	     cout << "2. Sort list by author." << endl;
	     cout << "3. Sort list by subject." << endl;
		 
		 cout << endl << " >> ";
		 cin >> sortList;
		 
		 switch (sortList)
		 {
		 case 1 : sortTitle(); break;
	     case 2 : sortAuthor(); break;
	     case 3 : sortSubject();
		 }
		 
	 cout << "End of list!" << endl;
	 }
  }
Last edited on
RLB31384 (15)
rest of code:

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void deleteByTitle()
{
	string titleToDel;
	node *temp1, *temp2;
	temp1 = start_ptr;
	bool found = false;

	if (start_ptr == NULL)
		cout << "The list is empty!" << endl;
	else
	{
		cout << " Enter the name of the title you wish to remove: " << endl;
		cout << endl << " >> ";
		cin >> titleToDel;

		temp1 = start_ptr;
		if (temp1->title == titleToDel)
		{
			start_ptr = start_ptr->nxt;
			delete temp1;
			found = true;
		}
		else
		{
			while (temp1->nxt != NULL && !found)
            { 
				temp2 = temp1;
				temp1 = temp1->nxt;
					
				if (temp1->title == titleToDel)
				{
					temp1->nxt = temp2->nxt;
					delete temp1;
					found = true;
				}
			
			
			
			}
        }
		if (found == true)
		{
			cout << "The title was found and deleted from the list." << endl;
		}
		else
		{
			cout << "Sorry, the title was not found in the list." << endl;
		}
	}	
}

void inputFromFile()
{
	 node *temp, *temp2;
	 string title, author, subject;
     ifstream myfile ("books.txt");
  
  if (myfile.is_open())
  {
    while (! myfile.eof())
    {
	  temp = new node;
      getline (myfile,temp->title);
	  getline (myfile,temp->author);
	  getline (myfile,temp->subject);
	  myfile.ignore(1,'\n');
      cout << title << author << subject << endl;
	  temp->nxt = NULL;
	
	  // Set up link to this node
	  if (start_ptr == NULL)
	  { 
		  start_ptr = temp;
	  }
	  else
	  { 
		  temp2 = start_ptr;
          // We know this is not NULL - list not empty!
          while (temp2->nxt != NULL)
          {  
			  temp2 = temp2->nxt;
              // Move to next link in chain
          }
          temp2->nxt = temp;
      }
	}
  }
  myfile.close();
    
}

void outputToFile()
{
	ofstream myfile;
    myfile.open ("books.txt");
	node *temp;
	temp = start_ptr;

	if (start_ptr != NULL)
	{
		myfile << start_ptr->title << endl << start_ptr->author << endl << start_ptr->subject << endl << endl;
		
		while (temp->nxt != NULL)
		{
			temp = temp->nxt;
			myfile << temp->title << endl << temp->author << endl << temp->subject << endl <<endl;
		}
		
	}
    else cout << "Unable to open file"; 

  	cout << "Save complete." << endl;
	myfile.close();
}

	

void main()
  {  
	  start_ptr = NULL;
	  
	  inputFromFile();
	  
	  do
	  {
	  cout << endl;
	  cout << "Please select an option : " << endl;
	  cout << "0. Exit the program." << endl;
	  cout << "1. Add a book to the end of the list." << endl;
	  cout << "2. Delete a book by title." << endl;
	  cout << "3. Display list." << endl;
      
	  cout << endl << " >> ";
	  cin >> option;

	  switch (option)
	    {
	      case 1 : add_node_at_end(); break;
	      case 2 : deleteByTitle(); break;
	      case 3 : displayList(); 
	    }
	}
     while (option != 0);
	 outputToFile();
}
RLB31384 (15)
Here is the code after putting in a class...the class compiles but crashes on startup..gives, Im using VS08.

Unhandled exception at 0x00415baa in CS 310 - Project 2.exe: 0xC0000005: Access violation reading location 0xcccccd2c.

library.h
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#include <algorithm>
#include <iostream>
#include <string>
#include <cctype>
#include <fstream>

using namespace std;

class Library
{
      public:
         Library(); //Creates an empty library without books and without authors.
      
		 void sortTitle();
		 void sortAuthor();
		 void sortSubject();
         void add_node_at_end();
		 void displayList();
		 void deleteByTitle();
		 void inputFromFile();
		 void outputToFile();
		 int option;
      
      private:
		 struct node
		 {  
			 string title; 
			 string author;         
			 string subject;     
			 node *nxt;
		 };
		  
		  node *start_ptr;
		  

          
      
};


mainprogram.cpp
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#include "library.h"


void main()
  {  
	  Library lib;
	  lib.inputFromFile();
	  
	  do
	  {
	  cout << endl;
	  cout << "Please select an option : " << endl;
	  cout << "0. Exit the program." << endl;
	  cout << "1. Add a book to the end of the list." << endl;
	  cout << "2. Delete a book by title." << endl;
	  cout << "3. Display list." << endl;
      
	  cout << endl << " >> ";
	  cin >> lib.option;

	  switch (lib.option)
	    {
	      case 1 : lib.add_node_at_end(); break;
	      case 2 : lib.deleteByTitle(); break;
	      case 3 : lib.displayList(); 
	    }
	}
     while (lib.option != 0);
	 lib.outputToFile();
}

RLB31384 (15)
library.cpp part 1
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#include "library.h"

Library::Library()
{
node *start_ptr = NULL;
int option = 0;
}


void Library::sortTitle()
{
	string titleOrder[50][3];
	int counter;
	int result = 0;
	string sort;
	node *temp;
	string tempArray[50];

    temp = start_ptr;
    cout << endl;
    if (temp == NULL)
		cout << "The list is empty!" << endl;
    else
	{ 
		// Load list of titles
		for (int i=0; temp != NULL; i++)
		{
			titleOrder[i][0] = temp->title;
			titleOrder[i][1] = temp->author;
			titleOrder[i][2] = temp->subject;
			temp = temp->nxt;
			counter = i + 1;
		}
	}
	//copy to tempArray
	for (int i=0; i < counter; i++)
	{
		tempArray[i] = titleOrder[i][0];
	}

	//tolower array for sort
	for (int i=0; i < counter; i++)
	{
		transform(titleOrder[i][0].begin(), titleOrder[i][0].end(), titleOrder[i][0].begin(),static_cast < int(*)(int) > (tolower));
	}

	//sort

	for (int i=0; i < counter; i++)
	{
		for (int ii=0; ii < counter-1; ii++)
		{
			result = titleOrder[ii][0].compare(titleOrder[ii+1][0]);
			if( result > 0 )
			{
				sort = titleOrder[ii][0];
				titleOrder[ii][0] = titleOrder[ii + 1][0];
				titleOrder[ii + 1][0] = sort;
				sort = tempArray[ii];
				tempArray[ii] = tempArray[ii + 1];
				tempArray[ii + 1] = sort;
				sort = titleOrder[ii][1];
				titleOrder[ii][1] = titleOrder[ii + 1][1];
				titleOrder[ii + 1][1] = sort;
				sort = titleOrder[ii][2];
				titleOrder[ii][2] = titleOrder[ii + 1][2];
				titleOrder[ii + 1][2] = sort;
			}
		}
	}
	for (int i=0; i < counter; i++)
	{
		titleOrder[i][0] = tempArray[i];
		cout << "Book #" << i+1 << endl;
		cout << "---------------------------------------" << endl;
		cout << "Title:   " << titleOrder[i][0] << endl;
		cout << "Author:  " << titleOrder[i][1] << endl;
		cout << "Subject: " << titleOrder[i][2] << endl << endl;
	}
}

void Library::sortAuthor()
{
	string authorOrder[50][3];
	int counter;
	int result = 0;
	string sort;
	node *temp;
	string tempArray[50];

    temp = start_ptr;
    cout << endl;
    if (temp == NULL)
		cout << "The list is empty!" << endl;
    else
	{ 
		// Load list of titles
		for (int i=0; temp != NULL; i++)
		{
			authorOrder[i][0] = temp->author;
			authorOrder[i][1] = temp->title;
			authorOrder[i][2] = temp->subject;
			temp = temp->nxt;
			counter = i + 1;
		}
	}
	//copy to tempArray
	for (int i=0; i < counter; i++)
	{
		tempArray[i] = authorOrder[i][0];
	}

	//tolower array for sort
	for (int i=0; i < counter; i++)
	{
		transform(authorOrder[i][0].begin(), authorOrder[i][0].end(), authorOrder[i][0].begin(),static_cast < int(*)(int) > (tolower));
	}

	//sort

	for (int i=0; i < counter; i++)
	{
		for (int ii=0; ii < counter-1; ii++)
		{
			result = authorOrder[ii][0].compare(authorOrder[ii+1][0]);
			if( result > 0 )
			{
				sort = authorOrder[ii][0];
				authorOrder[ii][0] = authorOrder[ii + 1][0];
				authorOrder[ii + 1][0] = sort;
				sort = tempArray[ii];
				tempArray[ii] = tempArray[ii + 1];
				tempArray[ii + 1] = sort;
				sort = authorOrder[ii][1];
				authorOrder[ii][1] = authorOrder[ii + 1][1];
				authorOrder[ii + 1][1] = sort;
				sort = authorOrder[ii][2];
				authorOrder[ii][2] = authorOrder[ii + 1][2];
				authorOrder[ii + 1][2] = sort;
			}
		}
	}
	for (int i=0; i < counter; i++)
	{
		authorOrder[i][0] = tempArray[i];
		cout << "Book #" << i+1 << endl;
		cout << "---------------------------------------" << endl;
		cout << "Author:   " << authorOrder[i][0] << endl;
		cout << "Title:  " << authorOrder[i][1] << endl;
		cout << "Subject: " << authorOrder[i][2] << endl << endl;
	}
}

void Library::sortSubject()
{
	string subjectOrder[50][3];
	int counter;
	int result = 0;
	string sort;
	node *temp;
	string tempArray[50];

    temp = start_ptr;
    cout << endl;
    if (temp == NULL)
		cout << "The list is empty!" << endl;
    else
	{ 
		// Load list of titles
		for (int i=0; temp != NULL; i++)
		{
			subjectOrder[i][0] = temp->subject;
			subjectOrder[i][1] = temp->title;
			subjectOrder[i][2] = temp->author;
			temp = temp->nxt;
			counter = i + 1;
		}
	}
	//copy to tempArray
	for (int i=0; i < counter; i++)
	{
		tempArray[i] = subjectOrder[i][0];
	}

	//tolower array for sort
	for (int i=0; i < counter; i++)
	{
		transform(subjectOrder[i][0].begin(), subjectOrder[i][0].end(), subjectOrder[i][0].begin(),static_cast < int(*)(int) > (tolower));
	}

	//sort

	for (int i=0; i < counter; i++)
	{
		for (int ii=0; ii < counter-1; ii++)
		{
			result = subjectOrder[ii][0].compare(subjectOrder[ii+1][0]);
			if( result > 0 )
			{
				sort = subjectOrder[ii][0];
				subjectOrder[ii][0] = subjectOrder[ii + 1][0];
				subjectOrder[ii + 1][0] = sort;
				sort = tempArray[ii];
				tempArray[ii] = tempArray[ii + 1];
				tempArray[ii + 1] = sort;
				sort = subjectOrder[ii][1];
				subjectOrder[ii][1] = subjectOrder[ii + 1][1];
				subjectOrder[ii + 1][1] = sort;
				sort = subjectOrder[ii][2];
				subjectOrder[ii][2] = subjectOrder[ii + 1][2];
				subjectOrder[ii + 1][2] = sort;
			}
		}
	}
	for (int i=0; i < counter; i++)
	{
		subjectOrder[i][0] = tempArray[i];
		cout << "Book #" << i+1 << endl;
		cout << "---------------------------------------" << endl;
		cout << "Subject:   " << subjectOrder[i][0] << endl;
		cout << "Title:  " << subjectOrder[i][1] << endl;
		cout << "Author: " << subjectOrder[i][2] << endl << endl;
	}
}
	
	 

void Library::add_node_at_end()
{
	ofstream outfile;
    outfile.open ("books.log");
	node *temp, *temp2;   // Temporary pointers
	int nodeNum = 1;

	// Reserve space for new node and fill it with data
    temp = new node;
	cin.ignore();
	cout << "Please enter the title of the book: ";
	getline(cin, temp->title);
	cout << "Please enter the author: ";
	getline(cin, temp->author);
	cout << "Please enter the subject: ";
	getline(cin, temp->subject);
	temp->nxt = NULL;

    // Set up link to this node
    if (start_ptr == NULL)
	{ 
		start_ptr = temp;
		nodeNum = 1;
    }
    else
	{ 
		temp2 = start_ptr;
		// We know this is not NULL - list not empty
		while (temp2->nxt != NULL)
		{  
			++nodeNum;
			temp2 = temp2->nxt;
			// Move to next link in chain
		}
		temp2->nxt = temp;
	}
	outfile << "Insertion into node: " << nodeNum << endl;
	outfile << "Book #" << nodeNum << endl;
	outfile << "=========================================" << endl;
	outfile << "Title: " << temp->title << endl;
	outfile << "Author: " << temp->author << endl;
	outfile << "Subject: " << temp->subject << endl << endl;
	outfile.close();
}

void Library::displayList()
{  
	int sortList = 0;
	node *temp;
     temp = start_ptr;
     cout << endl;
     if (temp == NULL)
       cout << "The list is empty!" << endl;
     else
	 {
		 cout << "Please select an option : " << endl;
		 cout << "0. Exit the list display." << endl;
	     cout << "1. Sort list by title." << endl;
	     cout << "2. Sort list by author." << endl;
	     cout << "3. Sort list by subject." << endl;
		 
		 cout << endl << " >> ";
		 cin >> sortList;
		 
		 switch (sortList)
		 {
		 case 1 : sortTitle(); break;
	     case 2 : sortAuthor(); break;
	     case 3 : sortSubject();
		 }
		 
	 cout << "End of list!" << endl;
	 }
  }
RLB31384 (15)
library.cpp part2
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void Library::deleteByTitle()
{
	ofstream outfile;
    outfile.open ("books.log");
	string titleToDel;
	node *temp1, *temp2;
	temp1 = start_ptr;
	bool found = false;
	int nodeNum = 1;

	if (start_ptr == NULL)
		cout << "The list is empty!" << endl;
	else
	{
		cout << " Enter the name of the title you wish to remove: " << endl;
		cout << endl << " >> ";
		cin >> titleToDel;

		temp1 = start_ptr;
		if (temp1->title == titleToDel)
		{
			start_ptr = start_ptr->nxt;
			found = true;
			nodeNum = 1;
		}
		else
		{
			while (temp1->nxt != NULL && !found)
            { 
				temp2 = temp1;
				temp1 = temp1->nxt;
				++nodeNum;
					
				if (temp1->title == titleToDel)
				{
					temp1->nxt = temp2->nxt;
					found = true;
				}
			}
        }
		if (found == true)
		{
			cout << "The title was found and deleted from the list." << endl;
			outfile << "Deletion of node: " << nodeNum << endl;
			outfile << "Book #" << nodeNum << endl;
			outfile << "=========================================" << endl;
			outfile << "Title: " << temp1->title << endl;
			outfile << "Author: " << temp1->author << endl;
			outfile << "Subject: " << temp1->subject << endl;

			delete temp1;
		}
		else
		{
			cout << "Sorry, the title was not found in the list." << endl;
		}
		outfile.close();
	}	
}

void Library::inputFromFile()
{
	 node *temp, *temp2;
	 string title, author, subject;
     ifstream myfile ("books.txt");
  
  if (myfile.is_open())
  {
    while (! myfile.eof())
    {
	  temp = new node;
      getline (myfile,temp->title);
	  getline (myfile,temp->author);
	  getline (myfile,temp->subject);
      myfile.ignore(1,'\n');
	  while (myfile.peek()=='\n')
	  {
	  myfile.ignore(1,'\n');
	  }
	  cout << temp->title << temp->author << temp->subject << endl;
	  temp->nxt = NULL;
	
	  // Set up link to this node
	  if (start_ptr == NULL)
	  { 
		  start_ptr = temp;
	  }
	  else
	  { 
		  temp2 = start_ptr;
          // We know this is not NULL - list not empty!
          while (temp2->nxt != NULL)
          {  
			  temp2 = temp2->nxt;
              // Move to next link in chain
          }
          temp2->nxt = temp;
      }
	}
  }
  myfile.close();
    
}

void Library::outputToFile()
{
	ofstream myfile;
    myfile.open ("books.txt");
	node *temp;
	temp = start_ptr;

	if (start_ptr != NULL)
	{
		myfile << start_ptr->title << endl << start_ptr->author << endl << start_ptr->subject << endl << endl;
		
		while (temp->nxt != NULL)
		{
			temp = temp->nxt;
			myfile << temp->title << endl << temp->author << endl << temp->subject << endl << endl;
		}
		
	}
    else cout << "The list is empty." << endl;

  	cout << "Save complete." << endl;
	myfile.close();
}
RLB31384 (15)
The error takes me to line 394 in library.cpp

where:
while (temp2->nxt != NULL)
{
temp2 = temp2->nxt;
is...well I took out the function..and then the program starts..but it crashed when I tried to add a node...same type of crash..and the error took me to another line of code where I used

while (temp2->next != NULL)

what do you suppose is causing it.not sure if its teh while or the temp2...or what..
RLB31384 (15)
seems a few of the other crashes take me to:

xstring
int __CLR_OR_THIS_CALL compare(const _Myt& _Right) const
{ // compare [0, _Mysize) with _Right
return (compare(0, _Mysize, _Right._Myptr(), _Right.size()));

I tried commenting out some of the things making it crash..seems like every function has something in it to make it crash...I tried making my node, not private..still crashes.
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