Ad:

C++ Discussion Thread
Marked Solved
Views: 815

Dec 3rd, 2009

Doubly linked list compile error

Expand Post »

Hi,

I'm trying to construct my first Doubly Linked List, but am having trouble compiling.

This is my program:

main.cpp :

c++ Syntax (Toggle Plain Text)
#include <iostream>
#include "node.h"
#include "doublylinkedlist.h"
using namespace std;
 
int main()
{
	system ("PAUSE");
	return 0;
}
#include <iostream>
#include "node.h"
#include "doublylinkedlist.h"
using namespace std;

int main()
{
	system ("PAUSE");
	return 0;
}

node.h :

c++ Syntax (Toggle Plain Text)
class Node
{
public:
	Node *pointertonextnode;//pointer to the next node of type node
	Node *pointertopreviousnode;//pointer to the previous node of type node
 
	int nodedatamember;//a node's data memeber
};
class Node
{
public:
	Node *pointertonextnode;//pointer to the next node of type node
	Node *pointertopreviousnode;//pointer to the previous node of type node

	int nodedatamember;//a node's data memeber
};

doublylinkedlist.h :

c++ Syntax (Toggle Plain Text)
class doublylinkedlist
{
public:
 
	Node *pointertofrontoflist;//pointer to front of list
	Node *pointertobackoflist;//pointer to back of list  
 
	//constructor to contruct a blank doubly linked list:
	doublylinkedlist()
	{
		pointertofrontoflist = NULL;
		pointertobackoflist = NULL;
	}
 
	void insertBeginningWhenListIsEmpty(doublylinkedlist List, Node newNode);
};
class doublylinkedlist
{
public:

	Node *pointertofrontoflist;//pointer to front of list
	Node *pointertobackoflist;//pointer to back of list  

	//constructor to contruct a blank doubly linked list:
	doublylinkedlist()
	{
		pointertofrontoflist = NULL;
		pointertobackoflist = NULL;
	}

	void insertBeginningWhenListIsEmpty(doublylinkedlist List, Node newNode);
};

doublylinkedlist.cpp :

c++ Syntax (Toggle Plain Text)
#include "doublylinkedlist.h"
 
void doublylinkedlist::insertBeginningWhenListIsEmpty(doublylinkedlist List, Node newNode)
{
	if(List.pointertofrontoflist == NULL)
	{
		List.pointertofrontoflist = newNode;
		List.pointertobackoflist = newNode;
		newNode.pointertonextnode = NULL;
		newNode.pointertopreviousnode = NULL;
	}
	else
	{
		cout << "Create a Insert before function";
		//insert before function
	}
}
#include "doublylinkedlist.h"

void doublylinkedlist::insertBeginningWhenListIsEmpty(doublylinkedlist List, Node newNode)
{
	if(List.pointertofrontoflist == NULL)
	{
		List.pointertofrontoflist = newNode;
		List.pointertobackoflist = newNode;
		newNode.pointertonextnode = NULL;
		newNode.pointertopreviousnode = NULL;
	}
	else
	{
		cout << "Create a Insert before function";
		//insert before function
	}
}

In Visual Studio, the first compile error reports:

Quote ...

error C2143: syntax error : missing ';' before '*'

Which is the line in bold within the doublylinkedlist.h file.

I can't see the error which would cause this, and so am stumped.

Could anyone point my error?

Many thanks for any help with this!

//-------------------------------------------------
(Full error list if that will help):

Quote ...

error C2143: syntax error : missing ';' before '*'
error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
error C2143: syntax error : missing ';' before '*'
error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
error C2061: syntax error : identifier 'Node'
error C2065: 'pointertofrontoflist' : undeclared identifier
error C2065: 'NULL' : undeclared identifier
error C2065: 'pointertobackoflist' : undeclared identifier
error C2061: syntax error : identifier 'Node'
error C2039: 'pointertofrontoflist' : is not a member of 'doublylinkedlist'
see declaration of 'doublylinkedlist'
error C2039: 'pointertofrontoflist' : is not a member of 'doublylinkedlist'
see declaration of 'doublylinkedlist'
error C2065: 'newNode' : undeclared identifier
error C2039: 'pointertobackoflist' : is not a member of 'doublylinkedlist'
see declaration of 'doublylinkedlist'
error C2228: left of '.pointertonextnode' must have class/struct/union

Last edited by Carrots; Dec 3rd, 2009 at 1:05 pm.

Similar Threads

inserting a node in middle of doubly linked list in C
doubly linked list--- help needed1 in C++
To create contact manager using doubly linked list(c++) in C++
Linked List in C
compile error in C++

Carrots

Reputation Points: 41

Solved Threads: 0

Junior Poster in Training

Offline

62 posts
since Mar 2009

Permalink

Dec 3rd, 2009

Re: Doubly linked list compile error

does your class doublylinkedlist know what a class Node is? if not, trying to create a pointer to one will surely result in an error.

EDIT: I tested it and that wasn't the problem.
I used the Visual Studio pre-compiled header, fixed the lines 7&8 in doublylinkedlist.cpp ( &newNode ) and it compiled fine.

Last edited by Topi Ojala; Dec 3rd, 2009 at 1:39 pm.

Topi Ojala

Reputation Points: 13

Solved Threads: 17

Junior Poster in Training

Offline

59 posts
since May 2009

Permalink

Dec 3rd, 2009

Re: Doubly linked list compile error

Thanks for helping Topi, but I'm still having problems.

Did I make a mistake with what you suggested?

main.cpp:

C++ Syntax (Toggle Plain Text)
#include <iostream>
#include "node.h"
#include "doublylinkedlist.h"
using namespace std;
 
int main()
{
	system ("PAUSE");
	return 0;
}
#include <iostream>
#include "node.h"
#include "doublylinkedlist.h"
using namespace std;

int main()
{
	system ("PAUSE");
	return 0;
}

node.h:

C++ Syntax (Toggle Plain Text)
#ifndef NODE.H
#define NODE.H
 
class Node
{
public:
	Node *pointertonextnode;//pointer to the next node of type node
	Node *pointertopreviousnode;//pointer to the previous node of type node
 
	int nodedatamember;//a node's data memeber
};
 
#endif
#ifndef NODE.H
#define NODE.H

class Node
{
public:
	Node *pointertonextnode;//pointer to the next node of type node
	Node *pointertopreviousnode;//pointer to the previous node of type node

	int nodedatamember;//a node's data memeber
};

#endif

doublylinkedlist.h:

C++ Syntax (Toggle Plain Text)
#ifndef DOUBLYLINKEDLIST.H
#define DOUBLYLINKEDLIST
 
#include "node.h"
class doublylinkedlist
{
public:
 
	Node *pointertofrontoflist;//pointer to front of list   
	Node *pointertobackoflist;//pointer to back of list  
 
	//constructor to contruct a blank doubly linked list:
	doublylinkedlist()
	{
		pointertofrontoflist = null;
		pointertobackoflist = null;
	}
 
	void insertBeginningWhenListIsEmpty(doublylinkedlist List, Node newNode);
};
 
#endif
#ifndef DOUBLYLINKEDLIST.H
#define DOUBLYLINKEDLIST

#include "node.h"
class doublylinkedlist
{
public:

	Node *pointertofrontoflist;//pointer to front of list   
	Node *pointertobackoflist;//pointer to back of list  

	//constructor to contruct a blank doubly linked list:
	doublylinkedlist()
	{
		pointertofrontoflist = null;
		pointertobackoflist = null;
	}

	void insertBeginningWhenListIsEmpty(doublylinkedlist List, Node newNode);
};

#endif

doublylinkedlist.cpp:

C++ Syntax (Toggle Plain Text)
#include "doublylinkedlist.h"
#include "node.h"
void doublylinkedlist::insertBeginningWhenListIsEmpty(doublylinkedlist List, Node newNode)
{
	if(List.pointertofrontoflist == NULL)
	{
		List.pointertofrontoflist = &newNode;////////////////////
		List.pointertobackoflist = &newNode;////////////////////
		newNode.pointertonextnode = NULL;
		newNode.pointertopreviousnode = NULL;
	}
	else
	{
		cout << "Create a Insert before function";
		//insert before fucntion
	}
}
#include "doublylinkedlist.h"
#include "node.h"
void doublylinkedlist::insertBeginningWhenListIsEmpty(doublylinkedlist List, Node newNode)
{
	if(List.pointertofrontoflist == NULL)
	{
		List.pointertofrontoflist = &newNode;////////////////////
		List.pointertobackoflist = &newNode;////////////////////
		newNode.pointertonextnode = NULL;
		newNode.pointertopreviousnode = NULL;
	}
	else
	{
		cout << "Create a Insert before function";
		//insert before fucntion
	}
}

Visual Studio says:

Quote ...

unexpected tokens following preprocessor directive - expected a newline

Really appreciate any help with this

Thanks!

Carrots

Reputation Points: 41

Solved Threads: 0

Junior Poster in Training

Offline

62 posts
since Mar 2009

Permalink

Dec 26th, 2009

Re: Doubly linked list compile error

should the "name" given in the preprocessor command match on lines 1 and 2 in doublylinkedlist.h ?

other than that I'm not sure what the problem might be ( or you might have figured it out by now

Topi Ojala

Reputation Points: 13

Solved Threads: 17

Junior Poster in Training

Offline

59 posts
since May 2009

Permalink

Dec 27th, 2009

Re: Doubly linked list compile error

Topi is on the right track I think. A portion of it has to do with your preprocessor directives. I've never seen one with a period in it and this is why I suppose. Most people use an underscore in place of the period (the convention is to name it after your header like you had done, but really it could be anything). So change those to NODE_H, DOUBLYLINKEDLIST_H etc.

NULL is something that is defined in a couple of the headers so it has to be in all caps. You need to include <iostream> for the NULL and the couts. Also you need to qualify cout one of 3 ways: either put std:: in front of it, std::cout, or put using std::cout; at the top of your file, or the last option put using namespace std; at the top of your file (which is the least favorable since you have to worry about all the names in that namespace conflicting with the code you've written.

jonsca

Sponsor

Featured Poster

Reputation Points: 1165

Solved Threads: 578

Quantitative Phrenologist

Offline

4,271 posts
since Sep 2009

This thread is solved

Either the thread starter or a moderator has marked this thread as solved. You can most likely trust the responses and answers given. There is most likely no reason for any further responses to be posted here. If you have a related question, please start a new thread in this forum instead.

This thread is more than three months old

No one has posted to this discussion for at least three months. Please let old threads die and do not reply to them unless you feel you have something new and valuable to contribute that absolutely must be added to make the discussion complete. Otherwise, please start a new thread in this forum instead.

Previous Thread in C++ Forum Timeline: right click

Next Thread in C++ Forum Timeline: No error, still no output

DaniWeb Message

Cancel Changes

User Name
Password