🔗 Linked List — nodes & pointers

Nodes joined by next pointers. Insert/remove at a known node is O(1) (rewire), but finding one is O(n). Reverse flips every pointer.

length

head

tail

index access

O(n)

head → … → null

head→1next→2next→3next→null

what just happened (say it out loud)

Run an operation to see it step by step.

사상: a linked list trades O(1) index access for O(1) structural edits: because nodes are separate allocations wired by pointers, inserting/removing is just rewiring — but there's no address arithmetic to jump to index i, so search is O(n).

▶ deep-dive videos — “linked list reverse pointers explained”