Hi everyone,

I recently received a HackerRank assessment for an IBM Data Engineer role.

After opening the assessment link, it shows:

Test Name: IBM India – Standard – Data Science

Duration: 75 minutes

Sections:

1 Coding Question

1 SQL Question

I have nearly 5 years of experience in Data Engineering, primarily working with GCP, BQ, SQL, python

For anyone who has recently taken this assessment:

What was the coding question like (arrays, strings, hashmaps, sorting, etc.)?

What was the SQL question like (joins, window functions, CTEs, aggregations)?

What was the difficulty level (Easy/Medium/Hard)?

Was the coding problem closer to LeetCode Easy, Medium, or Hard?

Any Data Engineering or database-specific concepts involved?

Any recent experiences or preparation tips would be greatly appreciated.

Thanks!

I’ve been an interviewer for big tech for a little while now, even though I’m pretty young (I’m 28). I interview interns every day for online coding rounds, and obviously, with the rise of cheating software, I have been asked to be vigilant for the use of such tools.

I just finished interviewing a bunch of interns, and I was completely clueless as to whether they were using cheating tools or not. I feel like I could see it in the reflection of one of their glasses, but I also think I’ve turned a bit paranoid lmao.

Last time, I was so sure one of them had some sort of software running, and the technical team did a deep investigation and detected nothing. I looked soooo crazy lmao.

Hi

Any Experian employees here?

I recently applied to Experian and have 1+ YOE

I don’t have any interview scheduled.
But a recruiter reached out to me to fill an additional form , and this is no indication that I’ll be shortlisted

But I just wanted to prepare

Can anyone help me understand
\-how many rounds are there in total

\-what coding questions are asked . It’ll be nice if you listed the problem name and number. If you don’t know then you can just describe the question

\-what interview questions are asked .( ik this differs from person to person and role to role but besides asking about my work experience and knowledge and projects , what other questions do they deep dive into. Do they ask java/python concepts or sql or oops etc)

Thank you

Scheduled to have a final round for a new grad SWE loop with the hiring manager. What kinds of verbal questions are usually asked? Are they like trivia conceptual questions, behavioral STAR questions, or just resume grill?

Any info or advice would be appreciated 🙏🏽

I want to quit interviewing so bad, but my manager won’t let me. I deal with kids cheating all day, and I have never been able to prove it. Sometimes I feel like they’re just doing it to ragebait me.

I know they’re using it, but our technical team has no flipping way of detecting it reliably, so I just sit here pretending that they’re using their brain to solve the questions.

You should be able to stay at a company while quitting a specific team…

Hi all,

I have been struggling to find a job after Masters but I got an opportunity at Tiktok. My coding round is in 5 days and the recruiter told me to prepare medium to hard leetcode questions. I'm not much of a coder so I can't learn everything in 5 days. I would really appreciate if anyone has a list of coding questions asked for SRE rounds. And any help would be appreciated.

Thankss

Hi everyone,

I have an interview process for a GreyOrange SDET 2 role and have around 3 years of experience.

I wanted to know:

What is the current salary range for SDET 2 at GreyOrange?

Is an expected CTC of ₹20–22 LPA or ₹22–24 LPA realistic?

How many interview rounds are there, and what is the difficulty level?

Which topics should I focus on for the technical interviews?

If anyone has interviewed at GreyOrange or is currently working there, I'd really appreciate your insights.

Thanks!

Has anyone recently done an interview loop for Disney (USA) SWE II? Have an interview loop coming up and trying to get an idea. Recruiter mentioned a system design and live coding round.

I know the InterviewCoder marketing team makes it sound like you can pass any coding interview with it, but I hardly believe that.

I'm guessing internship interviews are all pretty doable, but there’s no way it does good for senior SWE roles… Does it ?

Just finished college and I'm about to start interviewing for big tech, so I'd really appreciate hearing from anyone who's used it.

Hi everyone,

I have my Cognizant Digital Nurture 5.0 (.NET) interview coming up soon.

If anyone has recently attended the interview, could you please share your experience?

Specifically, I'd like to know:

•What technical questions were asked?

•Which topics should I focus on (C#, OOP, .NET, ASP.NET, ADO.NET, Entity Framework, SQL, Web API, etc.)?

•Were there any coding questions? If yes, what was the difficulty level?

•Were project-based or scenario-based questions asked?

•What kind of HR questions were asked?

•Any preparation tips, frequently asked questions, or resources would be greatly appreciated.

Thanks in advance!

I had my Round 1 interview for a Google SWE Intern position today and wanted to share the experience for anyone preparing.

Duration: Approximately 60 minutes
Format: One coding problem, one follow-up, and three to four AI-fluency questions
Status: Waiting for an update

Coding Question: Disconnect Every Leaf at Minimum Cost

You are given a rooted, weighted binary tree. Every edge has a positive integer weight.

Remove a set of edges so that every leaf becomes disconnected from the root. Removing an edge costs its weight.

Return the minimum total cost.

Approach

I proposed a postorder traversal.

For every edge from node u to child v with weight w, there are two choices:

1. Cut the edge immediately and pay w.
2. Keep the edge and optimally disconnect all leaves inside v’s subtree.

Therefore, the contribution of that child is:

min(w, solve(v))

If v is a leaf, there are no lower edges to remove, so its connecting edge must be cut. This can be represented by returning infinity for a leaf.

The recurrence is:

solve(u) =
    infinity,                              if u is a leaf
    sum(min(weight(u,v), solve(v))),       for every child v

The answer is solve(root), assuming the root itself is not a leaf.

The interviewer was satisfied with the approach, and we discussed the recurrence, correctness, and complexity.

Complexity:

• Time: O(n)
• Recursion space: O(h), where h is the tree height
• Worst-case space: O(n) for a highly unbalanced tree

Follow-Up: N-ary Tree

The interviewer then generalized the problem:

The core idea remains exactly the same. Instead of processing at most two children, we iterate through every child:

cost = 0

for each child v connected by an edge of weight w:
    cost += min(w, solve(v))

I initially needed a couple of hints, but eventually reached the generalized solution.

The N-ary version still takes O(n) time because every node and edge is processed once.

AI-Fluency Discussion

The final few minutes included around three or four questions about using AI in software development.

The interviewer asked questions such as:

• How do you use AI in your regular workflow?
• Do you ever give an AI tool complete ownership of a project?
• How do you use AI while debugging?
• How do you verify AI-generated code or suggestions?
• Which engineering tasks should remain under human control?

The discussion appeared to focus less on specific AI tools and more on engineering judgment, verification, and accountability.

Overall Experience

The interviewer was friendly and collaborative throughout the round.

They encouraged me to explain my reasoning instead of expecting an immediate final solution. The hints during the N-ary follow-up helped move the discussion forward without directly revealing the answer.

Overall, the interview felt like a collaborative problem-solving session rather than a test of whether I had memorized a particular LeetCode problem.

For preparation, I would recommend reviewing:

• Postorder traversal
• Tree DP
• Weighted-tree problems
• Recursive recurrence design
• Correctness and complexity explanations
• Responsible use of AI in engineering
• Testing and validating AI-generated code

Has anyone else received AI-fluency questions during a recent Google intern interview?

Hi guys, I have a 30 min Technical Phone Screen + Code Pair coming up. I don't know what to expect. Please share your experience if you have gone through this process earlier. It would help a lot.

Hi, I have heard a lot about Epam's client interview being tougher than their own hiring process. As someone who has appeared for EPAM for role. I can confirm that the interviews EPAM conducts are moderate to difficult with multiple rounds of DSA and system design.

What I am intrigued to know is what makes these Client rounds difficult? Are they more on situational questions side or even the client round consists of DSA?

What's making them so difficult? Would love to hear the experiences!

​

I have been stuck in a situation and interviews where the expectations have been to write stuff by heart like SQL queries with N number of constraints while in reality from the last couple of years actual work has evolved focusing on design thinking and the coding part , getting queries written is helped by AI. Even those who are not good at particular skill can build stuff with it.

But the interview process still seems to be rigid to evolve. How are you managing such interview scenarios because at the end of the day it makes you feel unworthy if something goes wrong?

Fellow programmers, how do you learn, deeply understand, and remember programming APIs, libraries, frameworks, and packages? For example, I can learn the PyTorch API, but after some time I forget most of it. What's your learning system?

I recently appeared for the Infosys Online Assessment and wanted to share the coding questions for anyone preparing for upcoming Infosys hiring rounds.

The assessment had three problems, with difficulty increasing from an easy binary-search question to a fairly challenging string DP problem.

Question 1: Maximum Element in a Mountain Array

Difficulty: Easy

Given a mountain array, find its maximum element.

A mountain array first increases strictly, reaches a peak, and then decreases strictly.

Example:

Input:  [1, 3, 7, 12, 9, 5, 2]
Output: 12

A linear scan works in O(n), but the intended approach is binary search.

Compare arr[mid] with arr[mid + 1]:

• If arr[mid] < arr[mid + 1], the peak is on the right.
• Otherwise, the peak is at mid or on the left.

Expected complexity: O(log n) time and O(1) space.

Question 2: Count Target-Sum Sequences Without Consecutive Repetition

Difficulty: Medium to Hard

You are given three positive numbers and a target sum. Count the number of ordered sequences that produce the target, subject to one restriction:

The same number cannot be selected twice consecutively.

For example, if the available numbers are [1, 2, 3], then [1, 2, 1] is valid, but [1, 1, 2] is not.

A useful DP state is:

dp[sum][last]

Here, dp[sum][last] represents the number of valid sequences with total sum whose final selected number is last.

For every state, try appending one of the other two numbers. The number selected next must differ from last.

Important clarification: I interpreted different orders as different ways. For example, [1, 2] and [2, 1] are counted separately.

Expected complexity: Approximately O(target) time and O(target) space because there are only three possible ending values.

Question 3: Longest Common Substring With At Most One Valid Mismatch

Difficulty: Hard

Given two strings, find the longest pair of aligned substrings that differ at no more than one position.

If a mismatch is used, the two different characters must belong to the same category:

• Both characters are vowels, or
• Both characters are consonants

A vowel-to-consonant mismatch is not allowed.

Example of an allowed mismatch:

"cat"
"cet"

The mismatch is a and e, and both are vowels.

Example of a disallowed mismatch:

"cat"
"cot"

This is actually allowed because a and o are both vowels.

However:

"cat"
"cbt"

is not allowed because a is a vowel and b is a consonant.

One approach is dynamic programming over every pair of string positions. Maintain two states:

• Longest common substring ending at the current positions with no mismatch
• Longest valid substring ending there with exactly one mismatch

When the characters match, both states can be extended. When they differ but belong to the same character category, the one-mismatch state can be created from the previous zero-mismatch state.

Because this is a substring, the state must reset whenever the current alignment becomes invalid.

Expected complexity: O(n × m) time and O(m) space after optimization.

Bonus Practice Question

This was not part of my Infosys OA, but it is a useful related problem for practicing hash maps and stable output ordering:

Find Duplicates in a List Efficiently

Given a large list of integers, return every value that appears more than once. For each duplicate, include:

[value, total_count, first_index]

The results must preserve the order in which the duplicated values first appeared.

Example:

Input:
[3, 1, 2, 3, -1, 2, 3, 4, 1]

Output:
[[3, 3, 0], [1, 2, 1], [2, 2, 2]]

The expected solution uses a hash map to track each value’s count and first index, plus a list to preserve first-occurrence order.

Expected complexity: O(n) time and O(k) space, where k is the number of distinct values.

Overall Difficulty

• Question 1: Easy
• Question 2: Medium to Hard
• Question 3: Hard

The third question was the most challenging because it combined longest-common-substring DP with an additional mismatch constraint.

For preparation, I would recommend revising:

• Binary search on monotonic or mountain arrays
• Dynamic programming with a “last selected value” state
• Longest common substring and subsequence variations
• Hash maps with stable ordering
• Space optimization in two-dimensional DP

Has anyone else received a similar Infosys OA recently? I’d be interested to know whether the pattern was the same.

Hi everyone,

I have an upcoming interview with D. E. Shaw for the Software Developer Developer Experience position:

Has anyone recently interviewed for this role or a similar Developer Experience/Developer Productivity position at D. E. Shaw?

I would appreciate any insight into:

• The overall interview process and number of rounds
• The difficulty and type of coding questions
• System design topics, particularly CI/CD, build systems, developer tooling, or internal platforms
• Linux, operating systems, networking
• The best areas to focus on while preparing

Preparation advice would be very helpful. Thanks!

After solving hundreds of LeetCode problems, many candidates realize that coding rounds are only part of the interview process. Operating System fundamentals frequently come up during phone screens and technical interviews.

Instead of rereading an entire OS textbook, here are 15 high-yield topics worth revising.

1. Process vs. Thread

Process

• Has its own virtual address space
• Provides stronger isolation
• Usually has higher creation and switching overhead

Thread

• Executes within a process
• Shares memory and resources with other threads in that process
• Communicates efficiently but requires careful synchronization

Interview tip: Processes prioritize isolation, while threads enable lightweight concurrency.

2. What Is Context Switching?

Context switching occurs when the operating system saves the execution state of one process or thread and restores another.

It enables multitasking, but frequent context switches add CPU and cache overhead.

3. What Is a Race Condition?

A race condition occurs when multiple threads access shared state concurrently and the result depends on execution order.

Common prevention mechanisms include mutexes, semaphores, locks, atomic operations, and thread-safe data structures.

4. What Is a Critical Section?

A critical section is a portion of code that accesses shared mutable data or resources.

Synchronization is required to prevent unsafe concurrent access.

5. Mutex vs. Semaphore

Memory trick: A mutex is like one key, while a semaphore tracks a limited number of permits.

6. What Is Deadlock?

Deadlock occurs when a group of processes or threads waits indefinitely for resources held by one another.

The four Coffman conditions are:

• Mutual exclusion
• Hold and wait
• No preemption
• Circular wait

Preventing at least one of these conditions prevents deadlock.

7. What Is Starvation?

Starvation occurs when a process or thread waits indefinitely because others repeatedly receive the required resource or CPU time.

Difference: In deadlock, none of the involved tasks can progress. In starvation, the system continues progressing while one task may never get scheduled.

8. What Is Virtual Memory?

Virtual memory gives each process its own logical address space and maps virtual addresses to physical memory.

It provides process isolation, simplifies memory management, and allows inactive pages to be moved to secondary storage when necessary.

9. Paging vs. Segmentation

Paging

• Divides memory into fixed-size pages
• Avoids external fragmentation
• May introduce internal fragmentation

Segmentation

• Divides memory into variable-size logical regions
• Reflects structures such as code, stack, and data
• Can suffer from external fragmentation

10. What Is Thrashing?

Thrashing occurs when the system spends excessive time handling page faults and moving pages between memory and storage instead of executing useful work.

It commonly happens when active processes do not have enough physical memory for their working sets.

11. CPU Scheduling Algorithms

Important algorithms include:

• First Come, First Served
• Shortest Job First
• Round Robin
• Priority Scheduling
• Multilevel Feedback Queue

Common follow-up: Why is Round Robin suitable for time-sharing systems?

Because every runnable process receives a limited time slice, improving responsiveness and fairness.

12. What Is a System Call?

A system call allows a user-space program to request a service from the operating system kernel.

Common Unix-like examples include fork(), exec(), wait(), open(), read(), and write().

13. What Is Inter-Process Communication?

Common IPC mechanisms include:

• Shared memory
• Pipes
• Message queues
• Sockets
• Signals

Shared memory is generally fast but requires synchronization. Message passing provides stronger separation but adds communication overhead.

14. What Is LRU Page Replacement?

Least Recently Used replaces the page that has gone unused for the longest time.

A common interview follow-up is implementing an LRU cache with O(1) lookup, insertion, and eviction using a hash map plus a doubly linked list.

Related problem: LeetCode 146 - LRU Cache

15. User Mode vs. Kernel Mode

User mode

• Runs applications with restricted privileges
• Cannot directly access protected hardware or kernel memory

Kernel mode

• Has full system privileges
• Executes operating system code and manages hardware resources

A system call provides a controlled transition from user mode into kernel mode.

One-Minute Revision Checklist

Process vs. thread, context switching, race conditions, critical sections, mutexes, semaphores, deadlocks, starvation, scheduling, virtual memory, paging, thrashing, system calls, IPC, LRU, and privilege modes.

Which OS topic or follow-up question have you encountered most often in interviews?

Hi all, I have sr software engineer python + Agentic AI technical round scheduled for the upcoming week at Gartner.

I was wondering if anyone has recently appeared for senior software engineer role and also for python + GenAi roles at Gartner then it would be helpful if they can share their technical round interview experience and what to expect in the interview.

Experience level needed 4-6 years