Rotate List — Step-by-Step Visualization

Algorithm Pattern

Find New Tail + Reconnect

Key Idea

Rotation = cut list at n-k and reattach the back to the front.

Step-by-Step Approach

1. Find length n
2. k = k % n
3. Advance to node at n-k-1
4. Reconnect: new_tail.next.prev=tail, tail.next=old_head, new_tail.next=null