What is the time complexity of the copy constructor in the LList class?

• A. O(1)
• B. O(log n)
• C. O(n)
• D. O(n^2)

Answer: (C)

Copying a linked list requires creating a new node for each existing node and linking them in the same order. To achieve a deep copy, you must visit every node in the original list, allocate a new node, copy its data, and connect it to the new list. Since this work happens once per node, the total effort scales linearly with the number of nodes, n. So the copy constructor runs in O(n) time. For an empty list the time is constant, but with n nodes the behavior is linear. The other options imply faster than linear or superlinear behavior, which doesn’t match the straightforward one-pass creation and linking of each node.