Write code to remove duplicates from an unsorted linked list.

#####Follow up How would you solve this problem if a temporary buffer is not allowed?

Implement an algorithm to find the nth to last element of a singly linked list.

Implement an algorithm to delete a node in the middle of a single linked list, given only access to that node.

#####Example: ######Input: the node ‘c’ from the linked list a->b->c->d->e ######Result: nothing is returned, but the new linked list looks like a->b->d->e

You have two numbers represented by a linked list, where each node contains a single digit. The digits are stored in reverse order, such that the 1’s digit is at the head of the list. Write a function that adds the two numbers and returns the sum as a linked list.

#####Example ######Input: (3 -> 1 -> 5) + (5 -> 9 -> 2) ######Output: 8 -> 0 -> 8

Given a circular linked list, implement an algorithm which returns node at the beginning of the loop.

#####Definition Circular linked list: A (corrupt) linked list in which a node’s next pointer points to an earlier node, so as to make a loop in the linked list.

#####Example ######Input: A -> B -> C -> D -> E -> C [the same C as earlier] ######Output: C

Given a linked list, write a function to reverse it.

#####Example #####Input: A -> B -> C -> D #####Output: D -> C -> B -> A

Detect and remove loop in a linked list.