💻 Coding Interview Questions

1️⃣ What is a linked list?
Answer: A linear data structure where elements point to the next element.

2️⃣ Singly vs Doubly Linked List?
Answer: Singly points forward; doubly points forward and backward.

3️⃣ What is a circular linked list?
Answer: The last node points back to the first node.

4️⃣ What is a stack?
Answer: LIFO data structure (Last In, First Out).

5️⃣ What is a queue?
Answer: FIFO data structure (First In, First Out).

6️⃣ What is a priority queue?
Answer: Elements are dequeued based on priority, not insertion order.

7️⃣ What is a deque?
Answer: Double-ended queue, insert/delete from both ends.

8️⃣ What is a hash map?
Answer: Stores key-value pairs for fast retrieval.

9️⃣ What is collision in hash tables?
Answer: Two keys map to the same index; resolved using chaining or open addressing.

🔟 What is a binary tree?
Answer: Tree data structure where each node has at most two children.