Clone a linked list with next and random pointer

/* Link list Node
struct Node {
    int data;
    Node *next;
    Node *random;

    Node(int x) {
        data = x;
        next = NULL;
        random = NULL;
    }
};*/

class Solution {
public:
    Node *copyList(Node *head) {
        if (!head) return nullptr;
        
        // First pass: Create copy nodes and insert them between original nodes
        Node* curr = head;
        while (curr) {
            Node* copy = new Node(curr->data);
            copy->next = curr->next;
            curr->next = copy;
            curr = copy->next;
        }
        
        // Second pass: Assign random pointers for the copy nodes
        curr = head;
        while (curr) {
            if (curr->random)
                curr->next->random = curr->random->next;
            curr = curr->next->next;
        }
        
        // Third pass: Separate the original and copied lists
        Node* original = head;
        Node* copy = head->next;
        Node* copyHead = copy;
        
        while (original && copy) {
            original->next = original->next->next;
            copy->next = copy->next ? copy->next->next : nullptr;
            original = original->next;
            copy = copy->next;
        }
        
        return copyHead;
    }
};