1. Append to a linked list
2. Insert a nth position to a linked list
3. Get nth node of a linked list given the index - returns the data at index
4. Delete a node from linked list - passing the index
5. Delete a node from linked list - passing the val
6. Find the length of the linked list - iteratively and recursively
7. Prepend a node to a linked list
8. Find the middle of a given linked list
9. Count the number of times a given int occurs in a linked list
10. Reverse a linked list - recursive and iterative
11. How to add an element in the middle of the linked list?
12. How to remove Nth Node from the end of a linked list?
13. How do you check if a given linked list contains a cycle?
14. How do you find the starting node of the cycle?
15. How do you find the third node from the end in a singly linked list?
16. How do you bubble sort a linked list?
17. How to merge two sorted linked lists?
18. Given a linked list and a value x, partition it such that all nodes less than x come before nodes greater than or equal to x.
19. How to remove duplicates from a unsorted linked list?
20. How to remove duplicates from a sorted linked list?
21. How to remove all elements from a linked list of integers which match with given value?

To do

3. How do you find the sum of two linked lists using Stack?
4. How to convert a sorted list to a binary search tree?
5. How to check if a given linked list is a palindrome?
6. How do you find the length of a singly linked list?