How to maintain multi-level skip list properties when insertions and deletions are done?

What is the time complexity of inserting an element at the beginning of a linked list?

A. O(1)

B. O(n)

C. O(log n)

D. O(n log n)

Which of the following is a disadvantage of linked lists compared to arrays?

A. Dynamic size

B. Random access

C. Ease of insertion and deletion

D. Memory overhead

What is a circular linked list?

A. A list where each node points to the next

B. A list where the last node points to the first node

C. A list where each node points to itself

D. A list where the nodes are in a circle

Which of the following is true about a doubly linked list?

A. Each node has one pointer

B. Each node has two pointers

C. It is a type of tree

D. It can be traversed in one direction only