Given the head of a singly linked list and a non-negative integer k, rotate the list to the right by k places and return the new head. Rotating by the list's full length brings it back to where it started, so only k mod n actually changes anything — the optimal solution leans on that by briefly making the list circularTemporary Circular LinkLinking the tail back to the head turns "wrap around to the front" into an ordinary next-pointer walk — no special-casing needed for indices that would otherwise fall off the end. The list is cut back into a normal (acyclic) one before returning.: link the tail back to the head, walk to exactly where the new tail belongs, and cut the circle there. The next node after that cut — found correctly even when it wraps around past the original last node — becomes the new head.