LinkedList vs. DynamicArray

get is $O(1)$ on DynamicArray, since it computes the slot directly, and $O(n)$ on LinkedList, since it has to traverse from an end. add to the end is amortized $O(1)$ on DynamicArray, since most adds are cheap but an occasional grow copies every element, and $O(1)$ every time on LinkedList, since it allocates and links one node without ever copying. remove(index) is $O(n)$ on both, but for different reasons: the array shifts every element after the gap to close it, while the linked list’s cost is the traversal to find the node. Once found, unlinking it is $O(1)$.

DynamicArray. Its get and set are $O(1)$, while LinkedList’s are $O(n)$, and the program’s access pattern is exactly indexed reads and writes.

With a direct reference to the node, the linked list skips the traversal entirely. Unlinking is just two reference reassignments, $O(1)$ regardless of the list’s length. The array has no equivalent shortcut: even given the position directly, it still has to shift every element after the removed one to close the gap, so it stays $O(n)$.