161. Reverse every k nodes in a doubly linked list.
162. Reverse every k nodes in a circular linked list.
163. Reverse every k nodes in a circular doubly linked list.
164. Convert a singly linked list into a balanced binary search tree.
165. Convert a doubly linked list into a balanced binary search tree.
166. Find the GCD of all elements in a singly linked list.
167. Find the GCD of all elements in a doubly linked list.
168. Find the GCD of all elements in a circular linked list.
169. Find the GCD of all elements in a circular doubly linked list.
170. Find the LCM of all elements in a singly linked list.
171. Find the LCM of all elements in a doubly linked list.
172. Find the LCM of all elements in a circular linked list.
173. Find the LCM of all elements in a circular doubly linked list.
174. Delete the last node of a singly linked list.
175. Delete the last node of a doubly linked list.
176. Delete the last node of a circular linked list.
177. Delete the last node of a circular doubly linked list.
178. Reverse the data of a singly linked list (without changing node links).
179. Reverse the data of a doubly linked list (without changing node links).
180. Reverse the data of a circular linked list (without changing node links).
181. Reverse the data of a circular doubly linked list (without changing node links).
182. Rotate a singly linked list counterclockwise by k positions.
183. Rotate a doubly linked list counterclockwise by k positions.
184. Rotate a circular linked list counterclockwise by k positions.
185. Rotate a circular doubly linked list counterclockwise by k positions.
186. Rotate a singly linked list clockwise by k positions.
187. Rotate a doubly linked list clockwise by k positions.
188. Rotate a circular linked list clockwise by k positions.
189. Rotate a circular doubly linked list clockwise by k positions.
190. Insert a node after every kth node in a singly linked list.
191. Insert a node after every kth node in a doubly linked list.
192. Insert a node after every kth node in a circular linked list.
193. Insert a node after every kth node in a circular doubly linked list.
194. Split a singly linked list into a list of even and odd values.
195. Split a doubly linked list into a list of even and odd values.
196. Split a circular linked list into a list of even and odd values.
197. Split a circular doubly linked list into a list of even and odd values.
198. Reverse the first half of a singly linked list.
199. Reverse the first half of a doubly linked list.
200. Reverse the first half of a circular linked list.