CS Fundamentals Rapid-Fire

Problem Rapid-fire questions across operating systems, networking, and data structures fundamentals, asking the candidate to explain each concept concisely rather than dive deep into one.

Be ready to discuss

• OS — processes and threads: the difference, context-switch cost, and when to reach for each.
• OS — scheduling and memory: common scheduling algorithms (round robin, priority, multilevel feedback), the four Coffman deadlock conditions and how to break them, and virtual memory, paging, page faults, and thrashing.
• Networking — the model: OSI versus TCP/IP layers and what actually lives at each layer.
• Networking — the request path: DNS resolution end to end (recursive resolver, root/TLD/authoritative, caching and TTLs), the TCP 3-way handshake, and HTTP versus HTTPS including what the TLS handshake adds.
• Data structures — complexity: time and space cost of arrays, linked lists, trees, hash maps, and heaps for insert, delete, search, and iterate.
• Data structures — selection: justifying one over another for a given constraint (hash map versus balanced tree when order matters; heap versus sorted array for top-k; array versus linked list for cache locality).
• Delivery: answers are expected to be crisp and correct across breadth, so practise stating the core idea in two sentences before elaborating.