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Printing my linked list in reverse order in C++

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So I'm fairly new to C++ and today I decided to sit down and understand how linked lists work. I'm having a lot of fun doing it so far, but I've encountered a problem when trying to print my linked list in reverse order (not reverse the order of the linked list!)

Also, I wanted to do this without having a double linked list:

#include <iostream>
#include <string>

using namespace std;

class LinkedList
{
    public:
        LinkedList()
        {
            head = NULL;
        }

        void addItem(string x)
        {
            if(head == NULL)
            {
                head = new node();
                head->next = NULL;
                head->data = x;
            } else {
                node* temp = head;
                while(temp->next != NULL)
                    temp = temp->next;

                node* newNode = new node();
                newNode->data = x;
                newNode->next = NULL;
                temp->next = newNode;
            }
        }
        void printList()
        {
            node *temp = head;
            while(temp->next != NULL)
            {
                cout << temp->data << endl;
                temp = temp->next;
            }
            cout << temp->data << endl;
        }

        void addToHead(string x)
        {
            node *temp = head;
            head = new node;
            head->next = temp;
            head->data = x;
        }

        int countItems()
        {
            int count = 1;
            for(node* temp = head; temp->next != NULL; temp = temp->next)
                ++count;
            return count;
        }

        void printReverse()
        {
            node* temp2;
            node* temp = head;
            while(temp->next != NULL)
                temp = temp->next;

            //Print last node before we enter loop
            cout << temp->data << endl;

            for(double count = countItems() / 2; count != 0; --count)
            {
                //Set temp2 before temp
                temp2 = head;
                while(temp2->next != temp)
                    temp2 = temp2->next;
                cout << temp2->data << endl;

                //Set temp before temp2
                temp = head;
                while(temp->next != temp2)
                    temp = temp->next;
                cout << temp->data << endl;
            }
            cout << "EXIT LOOP" << endl;
        }

    private:
        struct node
        {
            string data;
            node *next;
        }

    *head;
};

int main()
{
    LinkedList names;

    names.addItem("This");
    names.addItem("is");
    names.addItem("a");
    names.addItem("test");
    names.addItem("sentence");
    names.addItem("for");
    names.addItem("the");
    names.addItem("linked");
    names.addItem("list");

    names.printList();

    cout << endl;

    names.addToHead("insert");

    names.printList();

    cout << endl;

    cout << names.countItems() << endl;

    cout << "Print reverse: " << endl;
    names.printReverse();
    cout << endl;

    return 0;
}

Now I'm not sure exactly why my code crashes, any help is appreciated!

Thanks!