Queue - Linked List Implementation in C++

Queue - Linked List Implementation.cpp

// Queue - Linked List Implementation
#include<iostream>

using namespace std;

class Node
{
public:
    int data;
    Node *next;
};

class Queue
{
    Node *head;
    Node *tail;
    Node *prev;
    Node *temp;
    bool isEmpty()
    {
        return head == NULL;
    }
public:
    Queue()
    {
        head = NULL;
        tail = NULL;
    }

    void enqueue(int x)
    {
        temp = new Node;
        temp->data = x;
        temp->next = NULL;
        if(isEmpty())
        {
            head = temp;
            tail = temp;
        }
        else
        {
            prev = tail;
            tail->next = temp;
            tail = temp;
        }
    }

    void dequeue()
    {
        temp = head;
        head = head->next;
        delete temp;
    }

    void find(int x)
    {
        int i;
        for(i=1, temp = head;temp->next != NULL && temp->data != x;temp = temp->next, i++);
        if(temp->data == x)
        {
            cout << "Found at position:" << i << endl;
        }
        else if(temp->next == NULL)
        {
            cout << "Error: Number Not found..." << endl;
        }
    }

    void display()
    {
        if(!isEmpty())
        {
            for(temp = head; temp != NULL; temp=temp->next)
                cout << temp->data << " ";
            cout << endl;
        }
        else
        {
            cout << "Queue is Empty!" << endl;
        }
    }
};

int main()
{
    Queue q;
    q.display();
    q.enqueue(15);
    q.display();
    q.enqueue(25);
    q.display();
    q.enqueue(35);
    q.display();
    q.enqueue(45);
    q.display();
    q.find(15);
    q.dequeue();
    q.display();
    q.dequeue();
    q.display();
    q.dequeue();
    q.display();
}

This is not a Queue;

1. queue's disallow access to any element beyond the first, you can only push an item on to a queue, or pop an item off a queue, thus there should not be a find() function.
2. dequeueing should return the value of the first item on the queue, not delete the whole queue.
3. what purpose does display() serve? either dequeue or display() should return the value and then remove it from the stack.

What you have here is merely a linked list with odd access specifiers. Good try though.