1. Implement a skip list from scratch.
2. Reverse every alternate k nodes of a linked list and leave the others as they are.
3. Find the first node in a circular linked list that forms the smallest lexicographical order when traversed.
4. Perform addition of two numbers represented by two doubly linked lists.
5. Convert a multi-level doubly linked list into a flattened singly linked list.
6. Perform binary search on a sorted linked list.
7. Convert a linked list with arbitrary pointers to a deep copy linked list.
8. Find the maximum sum path between two intersecting linked lists.
9. Sort a linked list of 0s, 1s, and 2s in O(n) time.
10. Merge two sorted linked lists using a divide-and-conquer approach.
11. Convert a singly linked list to a circular doubly linked list while preserving the order.
12. Split a doubly linked list into k parts with minimal difference in node count.
13. Reverse k nodes of a doubly linked list using an iterative approach.
14. Perform multiplication of two numbers represented by two doubly linked lists.
15. Perform a radix sort on a linked list of integers.
16. Reverse alternate groups of k nodes in a circular doubly linked list.
17. Find the length of the longest strictly increasing subsequence in a doubly linked list.
18. Implement a lock-free concurrent linked list.
19. Rotate a linked list to the left by k nodes using bit manipulation.
20. Rotate a circular doubly linked list in O(n) time using constant space.
21. Perform matrix multiplication using linked lists.
22. Rearrange a linked list such that even and odd nodes alternate in O(1) extra space.
23. Implement a concurrent queue using a linked list.
24. Perform an in-order traversal on a binary tree represented by a linked list.
25. Implement a polynomial using a linked list and perform polynomial addition.
26. Split a circular doubly linked list into two halves with minimal time complexity.
27. Find the first node in a circular doubly linked list that starts the largest palindromic sequence.
28. Reverse a sublist of nodes between m and n in a doubly linked list.
29. Implement a self-balancing binary search tree using a doubly linked list.
30. Find the middle element of a circular doubly linked list in O(1) space.
31. Design and implement an LRU cache using a doubly linked list.
32. Implement a Fibonacci heap using a doubly linked list.
33. Convert a binary tree to a multi-level doubly linked list.
34. Implement the Floyd-Warshall algorithm using an adjacency list of linked lists.
35. Implement a red-black tree using a linked list.
36. Find the maximum product of two adjacent nodes in a circular doubly linked list.
37. Implement a linked list-based version of the Ford-Fulkerson algorithm for max flow.
38. Perform in-place sorting of a linked list using merge sort.
39. Convert a sorted circular doubly linked list to a balanced AVL tree.
40. Rearrange a linked list based on a given function f(x) such that f(x) is applied to each node.