Queue implementation using singly linked list

Question

if we implement queue using singly linked list then how juch time enqueue enqueue and dequeue will take ?

Answer 1

Queue using singly Linked List, enqueue will take O(n) and Dequeue will take O(1) time. 

Because for enqueue operation, insert at the tail of the linked list and for dequeue remove from the beginning of the linked list (FIFO).

but if we maintain an extra pointer both will take O(1).

Comments

but what about that case when we have to  delete the first node inserted after the  n nodes in that case dequeue will take O(n) time correct if i am wrong

---

But then it ll not remain queue...