How can I access a member from another class?

[crodriguez08]

Hey there, I can't seem to figure out why i can't access the member '*next' from the Node class in the Shuffle function. Any help would be great. Thanks.

/*  llist.h
 *  LList
 */

#include <iostream>
#include <string>

using namespace std;

typedef string ElementType;

class LList;
class Node {
protected:
	ElementType data;
	Node *next;

public:
	Node() {next=NULL;};
	Node(ElementType d) {data=d; next=NULL;}
	Node* GetNext() {return next;};
	ElementType GetData() {return data;};
	friend class LList;
	friend ostream& operator<< (ostream &, Node &);
	friend ostream& operator<< (ostream &out, LList &li);

	
};

class LList {
protected:
	Node *first;
	int mySize;
	
public:
	LList() {first = NULL; mySize = 0;}
	~LList();
	void Insert(ElementType, Node *);
	Node* InsertAndReturn(ElementType, Node *);
	void InsertFirst(ElementType);
	void Delete(Node *);
	void DeleteFirst();
	void DeleteAll();
	int FindFirst(ElementType);
	friend ostream& operator<< (ostream &out, LList &li);
	LList& operator= (const LList &li);
	friend LList* Shuffle(LList & , LList &);
	friend class Node;
};

/*  llist.cpp
 *  Implementation of member functions for the classes Node and LList.
 */

#include "llist.h"
using namespace std;


ostream& operator<< (ostream &out, Node &n)
{
	out << n.data;
	return out;
}

//
//	Destructor for the List class. Must remember to delete the linked list.
// 

LList::~LList() {
	while (first != NULL) {
		DeleteFirst();
	}
}

//
//	Preconditions: The list has been created
//	Postconditions: A node will be added after the one pointed by p.

void LList::Insert(ElementType e, Node* p) {
	Node *n = new Node(e);
	
	if (p == first) {
		n->next = first;
		first = n;
	}
	else {
		n->next = p->next;
		p->next = n;
	}
}

void LList::InsertFirst(ElementType e) {
	Insert(e,first);
}

Node* LList::InsertAndReturn(ElementType e, Node* p) {
	Node *n = new Node(e);

	if (p == first) {
		n->next = first;
		first = n;
	}
	else {
		n->next = p->next;
		p->next = n;
	}
	return n;
}

void LList::Delete(Node *p) {
	Node *n;
	if (p == first) {
		n = first;
		first = first->next;
	}
	else {
		n = p->next;
		p->next = n->next;
	}
	delete(n);
}

void LList::DeleteFirst() { Delete(first);}

int LList::FindFirst(ElementType e) {
	Node *p = first;
	int i = 0;
	while(p!=NULL) {
		if (p->data == e) return i;
		else { 
			p = p->next;
			i++;
		}
	}
	return -1;
}

void LList::DeleteAll() {
		Node *n;
		int i = 0;
		while (first != NULL) {
			n = first;
			first = first->next;
			cout << "deleting: " << i++ << endl;
			delete(n);
		}
}

ostream& operator<< (ostream &out, LList &li) {
	//	Traverse the list, printing each element
	Node *p = li.first;
	while(p!=NULL) {
		out << *p;
		p = p->next; 
		if (p!=NULL) out << ", ";
	}
	return out;
}

LList& LList::operator= (const LList &li) {
	Node* p;
	Node *r;
	p = li.first;
	r = this->first;
	while(p!=NULL) {
		//cout << "Copying: " << p->data << "  " ;
		r = this->InsertAndReturn(p->data,r);
		p = p->next; 
	}
	return *this;
}


LList* Shuffle(LList &L1, LList &L2){  // Function with errors
	LList L3;
	LList *L3 = new LList;

	Node *p1 = L1.first;
	Node *p2 = L2.first;
	Node *p3 = L3.first;

	L3.first = p1;
	p3 = L3.first;
	p3->next = p2;

	p1 = p1->GetNext();
	p2 = p2->GetNext();
	/*---------------------------------*/

	L3.first = p1;
	p3 = L3.first;
	p3->next = p2;
	p3 = p2;
	p1 = p1->GetNext();
	p2 = p2->GetNext();
	
	
	for(int i = 0; i < L1.mySize-1 ; i++){
		p3->next = p1;
		p3 = p1;
		p3->next = p2;
		p3 = p2;
		p1 = p1->GetNext();
		p2 = p2->GetNext();
	}
	

	return L3;
}

#include <iostream>
#include "llist.h"

int main (int argc, char * const argv[]) {

	
	LList *myTestList = new LList;
	
	cout << "will test insertion..." << endl;
	
	myTestList->InsertFirst("abanico");
	myTestList->InsertFirst("berro");
	myTestList->InsertFirst("caballo");
	myTestList->InsertFirst("dado");

	cout << myTestList << endl;
	
	
	cout << "will test delete..." << endl;
	
	myTestList->DeleteFirst();
	
	cout << "List after deleting the first element..." << endl;
	
	cout << myTestList << endl;

	cout << "Finding berro" << endl;
	cout << myTestList->FindFirst("berro") << endl;

	cout << "Finding dado" << endl;
	cout << myTestList->FindFirst("dado") << endl;
	
	//myTestList->DeleteAll();
	
	LList myTestList2;
	myTestList2 = *myTestList;
	cout << "This is the content of TestList2\n" << myTestList2 << endl;
	
	delete(myTestList);
	
	cout << "This is the content of TestList2 after delete of TestList1:\n" << myTestList2 << endl;


/*----------------------------------------------------------------------------------------------------------*/
	cout << "\nAdd an external friend function called 'Shuffle' that " << endl;
	cout << "takes as input two existing lists" << endl;
	cout << "(the ones using linked lists)and creates (and returns) " << endl;
	cout << "a shuffled list of the elements in the two lists." << endl; 
	
	
	LList *newlist1 = new LList;
	LList *newlist2 = new LList;
	LList *newlist3 = new LList;

	newlist1->InsertFirst("10");
	newlist1->InsertFirst("20");
	//newlist1->InsertFirst("30");
	//newlist1->InsertFirst("40");

	newlist2->InsertFirst("8");
	newlist2->InsertFirst("16");
	//newlist2->InsertFirst("24");
	//newlist2->InsertFirst("32");


	LList list1;
	LList list2;
	LList list3;

	list1 = *newlist1;
	cout << "\nThis is the content of List 1:\n" << list1 << endl;

	list2 = *newlist2;
	cout << "\nThis is the content of List 2:\n" << list2 << endl;

	//list3 = *newlist3;
	cout << "\nThis is the content of List 3:\n" << endl;
	newlist3 = Shuffle(list1, list2);
	//cout << list3 << endl;

/*------------------------------------------------------------------------------------------------------------*/

	int dummy;
	cout << "\nCreating a big list so that we can see impact in memory..\n";
	cin >> dummy;
	
	for (int i=0; i<10000; i++) {
		myTestList2.InsertFirst("porqueria");
	}
	
	cin >> dummy;
	delete(&myTestList2);
	
	cin >> dummy;
	
	LList *myTestList3 = new LList;
	cout << "Creating a big list so that we can see impact in memory..\n";
	cin >> dummy;
	
	
	for (int i=0; i<10000; i++) {
		myTestList3->InsertFirst("porqueria");
	}
	
	cin >> dummy;
	delete(myTestList3);
	
	cin >> dummy;
	
	return 0;
}

[hamsterman]

I'm not willing to compile your code myself. Explain in greater detail what is supposed to happen and what actually happens. You should only post the relevant parts of code. Also, try to debug yourself. That is an incredibly useful skill..