What does push_front() method do in the LList class?

What does push_front() method do in the LList class?

• A. Inserts at the end.
• B. Inserts at the beginning.
• C. Removes the last element.
• D. Clears the list.

Answer: (B)

Push_front inserts a new element at the beginning of the list. It creates a new node, makes its next point to the current head, and then updates the head to this new node. If the list was empty, you also set the tail to this new node. This operation is constant time since it doesn’t traverse the list. In contrast, inserting at the end, removing the last element, or clearing the list involve different link updates or traversals.

Push_front inserts a new element at the beginning of the list. It creates a new node, makes its next point to the current head, and then updates the head to this new node. If the list was empty, you also set the tail to this new node. This operation is constant time since it doesn’t traverse the list. In contrast, inserting at the end, removing the last element, or clearing the list involve different link updates or traversals.