linked list - crashes after inserting node to end of list

The program crashes at

Code:

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(*temp).next = NULL;

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Code:

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#include <cstdlib>
#include <iostream>
//#include <cstring>
#include <string.h>
#include "..\include\LinkedList.h"

LinkedList::LinkedList() : length(0), startPointer(NULL)
{

}

LinkedList::~LinkedList()
{

}

bool LinkedList::createNode(char name[])
{
    if(startPointer == NULL)
    {
        startPointer = new Node;
        strcpy((*startPointer).name, name);//can't just assign with = because can't do arr1[]=arr2[]
        std::cout << "Your name is: " << (*startPointer).name <<  std::endl;
    }
    else
    {
        Node *temp = startPointer;
        while((*temp).next != NULL)
        {
            temp = (*temp).next;
            /*This isn't working*/
            (*temp).next = NULL;
        }
        (*temp).next = new Node;
        strcpy((*temp).name, name);
        std::cout << "Your last name is: " << (*startPointer).name <<std::endl;
    }
    return true;
}

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Just for future referance, is it helpful if I leave in all the cout statment I use for debuging?

My crystal ball says that the default constructor for Node isn't setting the next pointer to NULL. This would cause your list to never be properly terminated, since you never do so explicitly in the createNode member function, and all loops that assume the list is NULL terminated will walk into oblivion. This often results in segmentation faults and crashes.

Quote:

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Originally Posted by Prelude

My crystal ball says that the default constructor for Node isn't setting the next pointer to NULL. This would cause your list to never be properly terminated, since you never do so explicitly in the createNode member function, and all loops that assume the list is NULL terminated will walk into oblivion. This often results in segmentation faults and crashes.

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Thanks but that doesn't seem to be the problem.

Post the smallest and simplest compilable program that demonstrates the problem.

main.cpp

Code:

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#include <iostream>
//#include <cstring>
#include "include\LinkedList.h"

using namespace std;

int main()
{
    LinkedList myList = LinkedList();
    cout << "Enter your name: ";
    char myName[20];
    cin.getline(myName, 20, '\n');
    myList.createNode(myName);
    cout << "Enter your last name: ";
    char myLastName[20];
    cin.getline(myLastName, 20, '\n');
    myList.createNode(myLastName);
    return 0;
}

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LinkedList.h

Code:

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#ifndef LINKEDLIST_H
#define LINKEDLIST_H

class LinkedList
{
    public:
        LinkedList();
        ~LinkedList();
        bool createNode(char name[]);

    private:
        unsigned int length;
        struct Node
        {
            char name[20];
            Node *next;
        };
        Node *startPointer;

};
#endif

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LinkedList.cpp

Code:

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#include <cstdlib>
#include <iostream>
//#include <cstring>
#include <string.h>
#include "..\include\LinkedList.h"

//default constructor
LinkedList::LinkedList() : length(0), startPointer(NULL){}

//destructor
LinkedList::~LinkedList(){}

bool LinkedList::createNode(char name[])
{
    if(startPointer == NULL)
    {
        startPointer = new Node;//Node is a struct
        strcpy((*startPointer).name, name);
        std::cout << "Your name is: " << std::endl;
    }
    else
    {
        Node *temp = startPointer;
        while((*temp).next != NULL)
        {
            temp = (*temp).next;
            /*This isn't working*/
            (*temp).next = NULL;
        }
        (*temp).next = new Node;
        strcpy((*temp).name, name);
    }
    return true;
}

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Quote:

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Originally Posted by c_weed

Thanks but that doesn't seem to be the problem.

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After looking at your code, I conclude that Prelude was correct. What made you conclude that Prelude's suggestion was off the mark?

Quote:

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Originally Posted by laserlight

After looking at your code, I conclude that Prelude was correct. What made you conclude that Prelude's suggestion was off the mark?

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Prelude was right. I got the next pointer confused with the startPointer.
So in my constructor I need

Code:

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Node.next = NULL;

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but then I get "error: expected unqualified-id before '.' token"

ah forget it, I'll start a new thread when I get my head wrapped around what question I should ask.