
Image credit to https://www.includehelp.com
Usually linked lists end with a node with no next reference, but we're looking for a sequence with a next pointer to a previous node. What might be the brute force solution here?
xxxxxxxxxx// 1 -> 3 <-> 5//      |//      7OUTPUT
:001 > Cmd/Ctrl-Enter to run, Cmd/Ctrl-/ to comment

