Doubly Linked List

#include <iostream>
using namespace std;

struct Node
{
    int data;
    Node* next;
    Node* prev;
};

Node* head = NULL;

Node* getNewNode(int x) {
    Node* newNode = new Node();
    newNode->data = x;
    newNode->next = NULL;
    newNode->prev = NULL;
    return newNode;
}

void insertHead(int x) {
    Node* newNode = getNewNode(x);
    if (head == NULL)
    {
        head = newNode;
        return;
    }
    head->prev = newNode;
    newNode->next = head;
    head = newNode;
}

void insertLast(int x) {
    Node* newNode = getNewNode(x);
    Node* trav = head;
    while (trav->next != NULL)
    {
        trav = trav->next;
    }
    trav->next = newNode;
    newNode->prev = trav;
}

void insertAny(int x, int pos) {
    if (pos == 1)
    {
        insertHead(x);
        return;
    }
    Node* newNode = getNewNode(x);
    Node* trav = head;
    for (int i = 1; i < pos - 1; i++)
    {
        trav = trav->next;
    }
    newNode->prev = trav;
    newNode->next = trav->next;
    trav->next = newNode;
    if (newNode->next != NULL)
    {
        newNode->next->prev = newNode;
    }
}

void deleteHead() {
    Node* del = head;
    head = del->next;
    delete del;
}

//void deleteLast() {
//  Node* trav = head;
//  while (trav->next != NULL)
//  {
//      trav = trav->next;
//  }
//  Node* del = trav->prev;
//  del->next = NULL;
//  delete del;
//}

void deleteLast() {
    Node* del = head;

    while (del->next != NULL)
    {
        del = del->next;
    }
    del->prev->next = NULL;
    delete del;
}

void deleteAny(int pos) {
    if (pos == 1)
    {
        deleteHead();
        return;
    }
    Node* trav = head;
    for (int i = 1; i < pos; i++)
    {
        trav = trav->next;
    }

    if (trav->next == NULL)
    {
        deleteLast();
        return;
    }
    Node* del = trav;
    trav->prev->next = trav->next;
    trav->next->prev = trav->prev;
    delete del;
}

void print() {
    Node* trav = head;
    while (trav->next != NULL)
    {
        cout << trav->data << " ";
        trav = trav->next;
    }
    cout << trav->data << " ";
}

int main() {
    insertHead(20);
    insertHead(10);
    insertLast(40);
    insertAny(30, 3);
    print();
    cout << endl;

    deleteHead();
    deleteLast();
    print();
    cout << endl;
    deleteAny(2);
    print();
    return 0;
}