CS/IT Questions

What is the time complexity of inserting a node at the beginning of a singly linked list?

• O(1)
• O(n)
• O(log n)
• O(n²)

Which data structure uses LIFO (Last-In-First-Out) principle?

• Queue
• Stack
• Heap
• Graph

What is the worst-case time complexity of QuickSort?

• O(n log n)
• O(n²)
• O(n)
• O(log n)

Which protocol is used for secure communication over a network?

• HTTP
• HTTPS
• FTP
• DNS

What does ACID stand for in databases?

• Atomicity, Consistency, Isolation, Durability
• Availability, Consistency, Integrity, Durability
• Atomicity, Concurrency, Isolation, Durability

Which layer of the OSI model handles routing and IP addressing?

• Transport Layer
• Network Layer
• Data Link Layer
• Application Layer

What is a primary use case for a B-tree?

• Storing hierarchical data
• Database indexing
• Graph traversal
• Sorting algorithms

Which sorting algorithm has a worst-case time complexity of O(n log n)?

• Bubble Sort
• Merge Sort
• Quick Sort
• Insertion Sort

What is the purpose of a semaphore in operating systems?

• Manage file systems
• Synchronize threads
• Allocate memory
• Handle interrupts

Which normal form eliminates transitive dependencies in a database?

• 1NF
• 2NF
• 3NF
• BCNF