singly linked list program

#include <iostream>
using namespace std;



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

    
    Node *head = new Node(); // special node pointer.

  void insertAtBeginning(Node* head, int data) {
        Node* temp = new Node();
        temp->data = data;
        temp->next = NULL;
        head->next = temp;
    }
    
    void insertAtEnd(Node* head, int data) {
        Node* temp = new Node();
        Node * current = head->next;
        while(current->next != NULL) {
            current = current->next;
        }
        current->next = temp;
        temp->data = data;
        temp->next = NULL;  
    }
    
    void display(Node* head) {
        Node* current = head->next;
        while(current != NULL) {
            cout << current->data << endl;
            current = current->next;
        }
    }
    
    void insertAtPosition(Node* head, int data, int pos) {
        Node* current = head->next;
        Node* temp = new Node();
        Node* prev = new Node();
        temp->data = data;
        
        if(head->next == NULL) {
            insertAtBeginning(head, data);
        }
        else {
        int i = 0;
         while(i < pos && current->next != NULL) {
            prev = current;
            current = current->next;
            i++;
        }
        
        if(current->next == NULL) {
        current->next = temp;
        temp->data = data;
        temp->next = NULL; 
        }
        
        else {
            temp = prev->next;
            prev->next = temp;
        }
    }
}

    void deleteAtEnd(Node*  head) {
        Node* current = head->next;
        Node* prev = new Node();
        
        
        while(current->next != NULL) {
            prev = current;
            current = current->next;
        }
        prev->next = NULL;
        free(current);
    }
    
    void deleteAtBeginning(Node* head) {
        Node* temp = new Node();
        temp = head->next;
        head->next = temp->next;
        
        free(temp);
    }
    
    void deleteAtPosition(Node* head, int pos) {
    Node * current = head->next;    
    Node * prev = new Node();
    int i = 1;
    if(head->next == NULL) {
        cout << "Cannot delete." << endl;
        return;
    }
    else {
        while(i < pos && current->next != NULL) {
            prev = current;
            current = current->next;
            i++;    
        }
        
        prev->next = current->next;
        free(current);
    }
}

int main() {
    
    insertAtBeginning(head,1);
    insertAtEnd(head,2);
    insertAtPosition(head, 3, 3);
    insertAtPosition(head, 40,4);
    insertAtPosition(head, 69, 5);
    deleteAtPosition(head, 3);
    display(head);
    
    
    return 0; 
}