Clone a linked list with next and random pointer-Optimised Approach

class Solution
{
    private:
    void insertAtTail(Node* &head, Node* &tail, int d){
        Node* newNode = new Node(d);
        if(head == NULL){
            head = newNode;
            tail = newNode;
            return;
        }
        else{
            tail->next = newNode;
            tail = newNode;
        }
    }
    public:
    Node *copyList(Node *head)
    {
        //step 1: create a clone list
        Node* cloneHead = NULL;
        Node* cloneTail = NULL;
        
        Node* temp = head;
        while(temp!=NULL){
            insertAtTail(cloneHead,cloneTail,temp->data);
            temp = temp->next;
        }
        //step 2: clone nodes add between original List
        Node* originalNode = head;
        Node* cloneNode = cloneHead;
        
        while(originalNode!= NULL && cloneNode!=NULL){
            Node* next = originalNode->next;
            originalNode->next = cloneNode;
            originalNode = next;
            
            next = cloneNode->next;
            cloneNode->next = originalNode;
            cloneNode = next;
        }
        //step 3: random pointer copy
        
        Node* curr = head;
        while(curr != NULL){
            if(curr->next != NULL){
                curr->next->arb = curr->arb ? curr->arb->next:curr->arb ;
                //after wirting above line you dont have to write the below 4 lines
                
            }curr = curr->next->next;
        }
        //step 4: revert changes done in step 2;
        originalNode = head;
        cloneNode = cloneHead;
        while(originalNode != NULL && cloneNode != NULL){
            originalNode->next = cloneNode->next;
            originalNode = originalNode->next;
            
            if(originalNode!=NULL){
                cloneNode->next = originalNode->next;
            }
            cloneNode = cloneNode->next;
        }
        //step 5: return ans
        return cloneHead;
        
    }

};