Data Structures · Question 17 · Easy
What is the time complexity of inserting a new node at the beginning (head) of a singly linked list of n nodes?
- O(n²)
- O(1)
- O(log n)
- O(n)
Answer and explanation
Answer: B. O(1)
Explanation: The new node's next pointer is set to the current head and head is updated to the new node. No traversal is needed, so it takes constant time.
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