Continued from Part 5. All earlier FastPrep links will be added after those parts have approved live URLs.

Coverage: Detailed timelines 33–36, covering the remaining 2019–2020 campus reports. This final part then turns the full 37-report set into a preparation order and checklist.

36 detailed candidate timelines, loops, and screens — continued

33: 2020 campus drive — four concrete OA tasks and three technical interviews

Report date: September 3, 2020 · Process: Campus placement · Result: Selected

Online test — HackerRank

1. Twenty MCQs on Networking, OS, and Linux/Unix.
2. Four coding questions. Two were worth 50 points and two were worth 70.
3. Binary grouping: move all 0s to one side and all 1s to the other by adjacent swaps. Return the minimum swaps. Either final order was allowed.
4. Bad index: start at 0. At step i, stay or move forward by i. Never land on one forbidden index. Return the largest position after k steps.
5. Ancestral sorting: sort names first, then sort their Roman-numeral suffixes numerically.
6. Repeated string: decide whether repeated copies of one string form another, then return the smallest string whose repetitions generate it.
7. About 430 students took the test. Twelve were selected for interviews.

Technical interview 1

1. Explain Quicksort complexity and how to guarantee O(n log n). This followed from a sorting-visualization project.
2. In a single-core system with 1 GB of RAM, three processes of 526 MB each are running. Explain how virtual memory allows this and discuss page replacement.
3. Explain DHCP, TCP versus UDP, what happens after entering a URL, what happens after connecting an Ethernet cable, and dynamic IP.
4. Return the maximum value in every subarray of size k.
5. Evaluate an expression tree.
6. Explain how to build the expression tree; time ran out before the candidate finished that discussion.

Technical interview 2

1. Discuss an online multiplayer game project: server choice, login authentication, database, and why MongoDB instead of MySQL.
2. Given comma-separated keys and comma-separated values stored in strings, parse them into a vector of key-value maps.
3. Explain parent, child, and zombie processes.
4. Compare a process and a thread. The candidate became confused, and the discussion continued for about ten minutes.
5. Return to the Bad Index OA problem and optimize repeated calls by saving results in advance.

Technical interview 3

1. Discuss the DevTest role.
2. Create a function pointer. The candidate could not remember the syntax.
3. Explain “virtualization” in C++; the candidate could not answer.
4. For char *ch = new char[10], explain heap and stack allocation and how to create ten character pointers.
5. Compress the input string in place. Maps and extra arrays were banned. The only spare space was at the end of the same buffer.
6. Example: aaaabbbca becomes a4b3c1a1.
7. The candidate worked for about an hour but did not finish.

HR

1. Reflect on the past two interview days.
2. Say what you remembered from Zscaler’s presentation.
3. Judge your own performance.
4. Discuss the DevTest role.

Three students received an internship plus full-time offer.

34: 2020 ASE / Cloud Operations — four OA problems and 35 fundamentals MCQs

Report date: September 14, 2020 · Roles: Associate Software Engineer and Cloud Operations Engineer · Process: On-campus · Result: Three offers

Online assessment

1. Four coding questions and 35 MCQs on OS, Networking, DBMS, and cloud services.
2. Presentation scheduling: given talk start/end times, choose the largest number one person can attend.
3. Wheel cipher: letters sit on a wheel; decode each character by moving k places anticlockwise.
4. Reverse function arguments: in Python, return a function that performs the same operation as a supplied function but reverses the argument order.
5. Equalize piles: piles have different heights. In one step, lower a taller pile to the next lower existing height. Return the minimum steps to make all piles equal.

Technical interview

1. Explain TCP and/or the OSI model.
2. Explain the full data flow after clicking a link.
3. Explain Python iterables, decorators, and generators.
4. Discuss common network commands.
5. The report says two coding tasks were also given but does not preserve them.

Managerial interview

1. Explain your role in each project.
2. Discuss ambitions and where you see yourself in three or four years.
3. Explain why you want to join Zscaler.
4. Say whether you prefer coding or testing and why.
5. Answer follow-ups about a habit mentioned in the introduction.

Seven students reached this round. Three received offers.

35: 2020 Associate Cloud Engineer — one long webcam interview

Interview date: August 26, 2020 · Role: Associate Cloud Engineer · Process: Campus recruitment · Result: No offer

1. Round one was online aptitude and coding. The report does not give the questions.
2. Shortlisted candidates then had an 80-minute webcam interview.
3. Explain thrashing and preemption.
4. Explain the C++ friend keyword.
5. Compare static and dynamic binding.
6. Explain a proxy server.
7. Answer questions about resume projects.
8. The report does not describe a separate HR round.

36: 2019 Cloud Operations — HackerRank, technical interview, then HR

Interview date: September 4, 2019 · Role: Cloud Operations Engineer · Process: On-campus · Result: No offer

1. A HackerRank test came first.
2. Candidates who passed took a technical interview.
3. Those who passed the technical round moved to HR.
4. The only preserved technical question is: explain how a TCP handshake works.
5. No OA prompt, duration, or follow-up was published.

What repeated often enough to prioritize

Tier 1: Practice until automatic

1. Medium DSA while speaking. Arrays, strings, linked lists, intervals, binary search, trees, heaps, and basic graph/DP tasks appear across recent and older reports. State assumptions, start with a clear baseline, and test the code.
2. Computer Networks from packet flow upward. Be able to connect TCP/UDP, DNS, DHCP, ARP, HTTP/HTTPS, TLS, IP/subnet/CIDR, gateways, routing, VPNs, and proxies. Several interviews kept asking follow-ups until the candidate’s model broke.
3. Operating Systems. Process/thread, synchronization, deadlock, virtual memory, paging, scheduling, context switches, and Linux basics recur across C, SDE, QA, DevTest, and SRE reports.
4. One interview language in depth. For C/C++, prepare memory and object internals. For Java, prepare OOP, collections, memory, and concurrency. Frontend candidates need JavaScript execution and React, not only DSA.

Tier 2: Be ready to explain deeply

1. Projects. Prepare two projects you actually know. Cover architecture, data flow, APIs, storage, testing, bugs, tradeoffs, your own work, and what you would change.
2. Optimization. Several candidates were asked to move from brute force to a better method, prove complexity, or fix a partly working solution.
3. Role-specific tools. DevTest and SRE reports add Linux, Git, SQL, Postman, API behavior, logs, and troubleshooting. UI reports add DOM, browser storage, JavaScript async behavior, and React edits.
4. SQL and DBMS. These are not in every SDE loop, but they appear repeatedly in Java, QA, DevTest, and older ASE reports.

Tier 3: Useful differentiators

1. Security context. Know why TLS, certificates, proxies, VPNs, and zero trust matter to Zscaler.
2. Low-level reasoning. Pointer arithmetic, allocation, endianness, padding, vtables, maps, and custom memory work mattered in the C/C++ tracks.
3. Honest behavior stories. Prepare concrete examples of failure, conflict, ownership, teamwork, learning, and a difficult tradeoff. Do not turn them into slogans.

Final checklist

Online assessment

☐ Do two timed 90–120 minute mocks with three or four coding problems.

☐ Do one mixed-language mock if your campus notice mentions Python plus Java/C++.

☐ Review arrays, strings, maps, linked lists, binary search, trees, heaps, graph traversal, and medium DP.

☐ Write original code and test edge cases. Several reports mention strict plagiarism checks.

Live coding

☐ Restate the input, output, and constraints before coding.

☐ Say what the first simple solution would cost.

☐ Explain why the optimized solution is correct.

☐ Test empty input, one item, duplicates, negative values, and boundaries when they apply.

☐ Practice coding while talking in a plain shared editor without autocomplete.

Computer Networks

☐ Explain the complete browser-to-server flow.

☐ Draw TCP setup and TLS setup as two separate sequences.

☐ Explain DNS, DHCP, ARP, routing, subnetting, CIDR, gateways, VPNs, and proxies.

☐ Practice one troubleshooting story using ports, ping, traceroute, DNS lookup, and logs.

OS and Linux

☐ Review processes, threads, scheduling, memory layout, virtual memory, synchronization, deadlock, and IPC.

☐ Know Linux boot and common commands if the role is SRE, DevOps, QA, or DevTest.

C/C++ or Java

☐ C/C++: pointers, allocation, storage classes, structs, padding, maps, virtual dispatch, compilation, and endianness.

☐ Java: interfaces, abstract classes, collections, exceptions, concurrency, synchronization, memory, and Singleton variants.

Resume and values

☐ Prepare a two-minute introduction.

☐ Prepare two projects that can handle ten minutes of follow-ups.

☐ Prepare six real stories: failure, conflict, ownership, teamwork, learning, and a hard tradeoff.

☐ Explain Zscaler in your own words, including proxy-based security and zero trust.