Thread: a strange error!!I can't understand why!!please help me!!

I'm using Visual C++ Studio compiler,Console Application ,when I debug my code,I edited some errors of code.After that
I exited debugging mode and I debuged again..But the arrow pointed to places that blank lines(did't have code),and value of parameters still changed ,totally values are not true or not suitable with lines arrow pointed to...Even I exited my compiler and open it again ,but this still didn't change... I don't understand why??....Please help me!!thanks very much....

Post code... and the error messages. and what version of Visual Studio it is.

I'm using Visual C++ 6.0,I think my code is true,It can compile and run,but when I debug,it has this error....

"NodeList.h"

Code:

#ifndef NODELIST_H
#define NODELIST_H
template <class Entry>
struct Node{
	Node();
	Entry entry;
	Node<Entry> * next;
	Node(const Entry &item, Node<Entry> * p =NULL);
};
#endif

"NodeList.cpp"

Code:

#ifndef NODELIST_CPP
#define NODELIST_CPP
#include "NodeList.h"
template <class Entry>
Node<Entry>::Node(){
	next = NULL;
}

template <class Entry>
Node<Entry>::Node(const Entry & item, Node<Entry> * p){
	entry = item;
	next = p;
}

#endif

"List.cpp"

Code:

#ifndef LIST_CPP
#define LIST_CPP
#include "List.h"

template <class Entry>
List<Entry>::List(){
	count = 0;
	pchinh = NULL;
	pcurrent = NULL;
	CurrentPosition = 0;
}

template <class Entry>
List<Entry>::~List(){
	while(!Empty())
		Remove();
}
	

template <class Entry>
List<Entry>::List(const List<Entry> & list0){
	Node<Entry> *psao, * pduyet = list0.pchinh;
	if (pduyet==NULL) pchinh = NULL;
	else
	{
		pchinh = psao = new Node<Entry> (pduyet->entry);
		while (pduyet->next != NULL)
		{
			pduyet = pduyet->next;
			psao->next = new Node<Entry>(pduyet->entry);
			psao = psao-> next;
		}
	}
	return sucess;
}

template <class Entry>
List<Entry>& List<Entry>::operator=(const List<Entry> & list0){
	Node <Entry> *ptam, *psao, *pduyet = list0.pchinh;
	count = 1;
	if (pduyet==NULL) ptam = NULL;
	else
	{
		ptam = psao = new Node<Entry> (pduyet->entry);
		while(pduyet->next!= NULL)
		{
			pduyet = pduyet->next;
			psao->next = new Node<Entry>(pduyet->entry);
			psao = psao -> next;
			count++;
		}
	}
	while(!Empty())
		Remove();
		pchinh = ptam;
		return (*this);
}

template <class Entry>
ErrorCode List<Entry>::Insert(const Entry&item, int position){
	Node <Entry> *ptruoc, *psau, *newnode = new Node<Entry>(item);
    if (newnode == NULL)
	{
		 cout<<"Da het bo nho!Khong cap phat duoc nua.";
		 return overflow;
	}
	if (position < 0 || position > count)
	{
		cout<<"Vi tri chen khong hop le!";
		return errorrange;
	}

	if (position == 0)
	{
		if (pchinh ==NULL)
		{
		pchinh = newnode;
		count++;
		return sucess;
		}
		else
		{
		newnode -> next = pchinh;
		pchinh = newnode;
		count++;
		return sucess;
		}
	}
	else
	ptruoc = SetPosition(position-1);
	psau = ptruoc->next;
	newnode->next = psau;
	ptruoc -> next = newnode;
	count++;
	return sucess;
}

template <class Entry>
ErrorCode List<Entry>::Remove(int position){
	Node<Entry> * psau, *ptruoc, *ptam = pchinh;
	if (position < 0 || position >= count)
	{
		cout<<"Vi tri xoa khong hop le!";
		return errorrange;
	}
	if (position == 0)
		if (pchinh == NULL)
		{
			cout<<"Chua co phan tu nao de xoa!";
			return errorcode;
		}
		else
		{
		pchinh = pchinh->next;
		count--;
		delete ptam;
		return sucess;
		}
	else
		ptruoc = SetPosition(position-1);
		psau = ptruoc->next;
		ptam = psau;
		psau = psau -> next;
		delete ptam;
		count--;
		return sucess;
}

template <class Entry>
ErrorCode List<Entry>::Replace(const Entry &item, int position){
	Node<Entry> * psau, *ptruoc;
	if (position < 0 || position > count)
	{
		cout<<"Vi tri thay the khong hop le!";
		return errorrange;
	}

	if (position == 0)
		if (pchinh==NULL)
		{
			cout<<"Chua co phan tu nao de thay the!";
			return errorcode;
		}
		else
		{
		pchinh->entry = item;
		return sucess;
		}
	else
	ptruoc = SetPosition(position-1);
	psau = ptruoc->next;
	psau->entry = item;
	return sucess;
}

template <class Entry>
ErrorCode List<Entry>::Retrieve(Entry &item,int position){
	Node<Entry> * psau, *ptruoc;
	if (position < 0 || position > count)
	{
		cout<<"Vi tri tim khong hop le!";
		return errorrange;
	}

	if (position == 0){
		item = pchinh->entry;
		cout<<item<<endl;
		return sucess;
	}

	else
	{
		ptruoc = SetPosition(position-1);
		psau = ptruoc -> next;
	}
		
	item = psau->entry;
	cout<<item<<endl;
	return sucess;
}

template <class Entry>
Node<Entry> * List<Entry>::SetPosition(int position) const{
	Node<Entry> * ptam = pchinh;
	if (CurrentPosition > =position)
	{
	for (int i =0;i<position;i++)
		ptam = ptam->next;
		pcurrent = ptam;
		CurrentPosition = position;
		return ptam;
	}
	else
		for (int i = CurrentPosition;i<position;i++)
			pcurrent = pcurrent -> next;
			CurrentPosition = position;
			return pcurrent;
}

template <class Entry>
int List<Entry>::Size()const {
	return count;
}

template <class Entry>
bool List<Entry>::Empty() const {
	if (count == 0)
		return true;
	else
	return true;	
}

template <class Entry>
bool List<Entry>::Full() const{
  NodeList<Entry> * location;
  try
  {
    location = new NodeList<Entry>;
    delete location;
    return false;
  }
  catch(std::bad_alloc exception)
  {
    return true;
  }
}

template <class Entry>
void List<Entry>::Clear() const {
	int i;
	while (count!=0)
		Remove(i);
}

template <class Entry>
void List<Entry>::Traverse(void (*duyet)(Entry & item)){
	Node<Entry> * ptam= pchinh;
	for (int i =0;i<count;i++)
	{
		(*duyet)(ptam->entry);
		ptam = ptam->next;
	}
}

#endif

"List.h"

Code:

#ifndef LIST_H
#define List_H

#include "NodeList.h"
enum ErrorCode{sucess, underflow, overflow, errorrange, errorcode};
template <class Entry>
class List{
	public:
	List();
	~List();
	List(const List<Entry> &);
	List<Entry> &operator=(const List<Entry> &);
	int Size() const;
	void Clear() const;
	bool Empty() const ;
	bool Full() const;
	ErrorCode Insert(const Entry &item = 0, int position = 0);
	ErrorCode Remove(int position = 0);
	ErrorCode Replace(const Entry &item = 0 ,  int position = 0 );
	ErrorCode Retrieve(Entry &item , int position = 0);
	void Traverse(void (*duyet)(Entry&x));
	private:
		int count;
		Node<Entry> * pchinh;
		mutable int CurrentPosition;
		mutable Node<Entry> * pcurrent;
	protected:
		Node<Entry> * SetPosition(int position) const;
};

#endif

"UseList.cpp"

Code:

#include "stdafx.h"
#include "List.cpp"
#include "NodeList.cpp"
#include <iostream>
#include <conio.h>
using namespace std;

void main(){
	List<int> list1;
	List<int> list2;
	int i;
	list1.Insert(2);
	list1.Insert(4,1);
	list1.Insert(7,2);
	list1.Insert(12,3);
	list1.Insert(14,4);
	list1.Insert(9,5);
	//list1.Remove(4);
	list1.Replace(5);
	list1.Replace(9,3);
	list2 = list1;
	getch();
}

Example when I debug Remove function I have arrow:

Code:

template <class Entry>
ErrorCode List<Entry>::Remove(int position){
	Node<Entry> * psau, *ptruoc, *ptam = pchinh;

arrow point here although don't have code this line

After that arrow is here	if (position < 0 || position >= count)
	{
		cout<<"Vi tri xoa khong hop le!";
		return errorrange;
	}

After that Arrow points here(don't have code this line)

	if (position == 0)
		if (pchinh == NULL)
		{
			cout<<"Chua co phan tu nao de xoa!";
			return errorcode;
		}
		else
		{
		pchinh = pchinh->next;
		count--;
		delete ptam;
		return sucess;
		}
	else
		ptruoc = SetPosition(position-1);
		psau = ptruoc->next;
		ptam = psau;
		psau = psau -> next;
		delete ptam;
		count--;
		return sucess;
}

So Value of parameters change and I can't manage them....

> http://cboard.cprogramming.com/showthread.php?t=83656
Why do you still have bits of your templates in .cpp files?

> I'm using Visual C++ 6.0
Are you completely up to date with service packs ?
VC6 template handling is pretty poor by comparison with more modern compilers.

Since Visual Studio express is free, I would suggest you get that as well.

I'm using service packs 6 of visual C++ 6.0
My program is true,it can compile and run,but in debugging mode ,sometimes I have this error,only when I edit code in debugging mode,if I exit debugging mode and edit,It OK...
I think if we can divide files that are very long into file shorter,It's good....
please tell me where I can get Visual Studio express....
Thanks for your interesting.....
Like you saw,my codes are very long,if I write them into a file it's very long and hard for me to edit,find error...

If you can ,you can show me way to write code better that is easy to manage code,edit code, find error...Thanks very much

http://msdn.microsoft.com/vstudio/express/

> only when I edit code in debugging mode,if I exit debugging mode and edit,It OK
Ah, the edit and continue feature.
I say live with it.
VSE might make a better job of it, but edit-continue does some pretty horrid things and no doubt templates don't make it any easier either.


> Like you saw,my codes are very long,if I write them into a file it's very long
I would suggest you fully debug your linked list using say just ONE type (say an int), using regular source files. Only when it's fully debugged do you make it a template for any type.

I mean, if it works for int, then it will work for string, double, messages, lists or anything else you can think of.


> void main()
It's int main you know - see the FAQ

Originally Posted by Salem

> void main()
It's int main you know - see the FAQ

Or see Salem's avatar.