Detect a loop in a linked list (3 methods)

A linked list a liner data structure. A linked list can be of many type. Some popular linked lists are given below:

Single Linked List
Double Linked List
Circular Linked List
Double Circular Linked List
Header Linked List

A Loop in a linked list is a condition when a Linked list does not have any end. That means the last pointer does not point to null in case of single and double linked list and to the head of the linked list in case of circluar linked list insted it points to some other node ...