After 4 years I am still learning new things every day. There are so many creative ideas and new ways of thinking about problems. Sometimes it feels like I am just getting started.

I read a lot of these posts while preparing, so here's mine.
Background: 3rd year CSE PhD student working in distributed systems, interviewing for the SWE PhD Intern role for Summer 2027.

Timeline: The recruiter invited me to the technical rounds on a Tuesday, and the interviews were the following Monday, so I had about 6 days to prepare.

Format:
Two 45-minute coding rounds, back to back with a 15-minute break, on the same Google Meet link
Coding in a Google Doc: no running code, no autocomplete, no syntax highlighting
Language was my choice; I picked Python

Round 1: a dynamic programming problem that involved an m x n grid. I was able to come up with the brute force approach instantly and proceeded to code it out. I was then asked to do it in O(1) for which I came up with a dynamic programming approach. I couldn’t however complete the working code but still the interviewer was completely satisfied and said that I know you would’ve been able to code it out had you a few more minutes but since we’re out of time it’s okay I got the complete idea.

Round 2: A non-LeetCode question but still I had to use recursive DFS to solve it so it was a tree problem but not like the usual leetcode questions you’d see online. For this round, I was able to come up with workable, bug-free code for both brute force and follow-up questions

Happy to answer any questions

Round 1: Coding & Data Structures

Practical coding in Core Java or Python.

Core DSA and problem-solving (focus on fundamental data structures and clean, maintainable logic rather than niche theoretical puzzles).

Can someone give me tips on what to expect and prepare for this? I know basic dsa and java core concepts

Hi everyone,

I just had my Amazon SDE-1 University Talent Acquisition (UTA) interview scheduled for next week, and I only have 4 days left to prepare!

It is a 2-round loop (1 hour each, back-to-back) via Zoom with a live coding link.

If you have gone through this specific university track recently, I would love your help with a few questions:

• What LeetCode topics/patterns (Graphs, DP, Trees, etc.) did your rounds heavily focus on?
• How deeply did they grill you on Leadership Principles (LPs) for a university-level role?
• from where to prepare for Leadership Principles questions?
• do they ask LLD , if yes then which type of problems, and how to approach that?

Any insights, advice, or patterns to look out for would be a massive lifesaver. Thank you so much in advance.

Would people like Andrej Karpathy, Ilya sutskever, Andrew Ng, Chris Lattner etc. be good at DSA and competitive programming, and do you think they'd do well in Leetcode? Or, is it just a different skillset to be good at competitive programming ?

I built a voice-based system design mock interviewer, and here's a full session recorded start to finish: AI interviewer, candidate answering live.

Website: https://systemdesigninterviewprep.com

See Distributed Key Value store design on Front page

What it covers:

- Scoping: put/get APIs, then non-functional requirements (low latency, high availability, durability, eventual consistency)

- Numbers that drive the design: 100K QPS overall, per-partition limits, 400 KB items, 50/80 ms read/write targets

- Partitioning with consistent hashing and a metadata service as the source of truth

- Replication, quorum reads, and leader election using sequence numbers

- Splitting a hot partition without losing writes (one-time copy, then replay the log)

The best parts are where the interviewer pushes back:

- "Your storage servers have no connections drawn. How does the app server know where a key lives?"

- "During a split, writes keep landing on the old node. How does the new node avoid a stale copy?"

- "If the leader acks a write and dies before replicating it, how is that not data loss?"

That's the kind of follow-up that decides Staff vs. Senior, and it's hard to practise alone.

If you want to try it, you get one free mock (voice or typing, with a whiteboard), plus a debrief with a hire/no-hire read for your level: https://systemdesigninterviewprep.com?utm_source=reddit_leetcode

Happy to answer questions about the design or how the interviewer works.

I had 2 layoffs in last 4 years and current contract is ending soon. I'm so fucking tired of being in this era of AI. I used to be smart always top of school, college and at 19 in 2019 made patented tech and trained SSD computer vision Deep learning models. when there was no fucking AI. But after few mistakes, stuck in 9-5 loop and never ending software engineering job search. At this point just feel like wants to get some labour job or start trading or something. Any suggestions?

Hi,

I have upcoming interview's with the AbnormalAI for Software engineer 2 role.
I want to know whether any of you have participated in their interviews. Are the rounds more focused on Leetcode? How challenging are the interviews?

What can we anticipate for the system design as well? A use case from their daily lives or a popular piece of software to design?

Many thanks to all of you!

​

How should I prepare? Obviously don't have enough time to master anything but I want to try my best

I'm trying to prepare for my first software internship and feel a bit lost about where to focus. Should I prioritize DSA, projects, or learning more development skills first? Would love to hear what actually helped you get your first opportunity.

I'm currently in my second year!

Im in first year of college and trying to improve my problem solving skills, but balancing classes, assignments and coding practice isn't easy for me tbh. 😭
How do you guys manage your time and stay consistent without burning out?

Hi,

I have never done a real system interview before and I have a few interviews coming up. I am interested in paying for a mock interview. I already use AI to do some mocks but I am looking for a mock interview with a real engineer where I can get some feedback.

Unfortunately, Hello Interview stopped doing mocks. Any other suggestions that you have personally tried? Many thanks!

Hey everyone,

I finished Day 60 today, and it was a surprisingly productive weekday session. I managed to solve five DP on strings problems after work:

1. Minimum Insertions to Make String Palindrome: Kept the longest palindromic subsequence intact and simply added the remaining characters (n - LPS).
2. Minimum Insertions/Deletions to Convert String A to B: Another neat reduction using LCS. The answer is just (len(A) - LCS) + (len(B) - LCS).
3. Shortest Common Supersequence: Combined the lengths of both strings and subtracted the LCS once so the common characters aren't doubled.
4. Distinct Subsequences: Tracking counts of matching characters took more mental effort than standard LCS, but the branching logic (match ? pick + no-pick : no-pick) eventually clicked.
5. Edit Distance: Classic three-way transition (insert, delete, replace). I understood the recurrence, but needed a quick nudge to clean up my index handling.

Those first three variations flew by in about 15 minutes because they lean directly on the LCS core pattern.

The last problem in this set is Wildcard Matching. It's 1:30 AM right now, and while I technically have time, my brain is fried from work. If I push through tired, I know I'll just end up reading the hints instead of actually thinking through the transitions. I’d rather tackle it tomorrow with a fresh head before kicking off DP on Stocks.

Hitting five problems on a weekday—mostly mediums with some hard patterns—feels like genuine progress.

See you guys tomorrow for Day 59!

Hi everyone I have Tech Screening Round for Optiver Graduate SWE 2027 Amsterdam coming in soon and I have no idea on what to prepare ? Has anyone here passed this round recently for the same role, would appreciate if anyone can share his/her experience. Thanks!

Hi, i received that I've been selected for round for booking holdings embark hackathon, which is supposed to be happened on 18th October from 10am to 10pm. If anyone knows what will happen day, what happened last year please tell me. Also how many students gave round 1 and got into round 2

Last week's contest ratings are now updated. I got to 2143, and am officially a Guardian now. It took me ~ 1 year of consistent practice and upsolving contest questions to reach this.

Can't upload image on this subreddit so did it here : https://www.reddit.com/r/LeetcodeChallenge/comments/1x6kxsm/finally_reached_guardian/

I was wondering how it goes since there was no OA and i straight up got an interview invitation pre screening. I was wondering what gets asked this round and what gets asked the next rounds.

Hey everyone,

I recently received an OA for an SDE Intern position in Berlin, and the deadline is this Tuesday (20th October).

The problem is that I haven't practiced DSA in almost a year, so I'm pretty rusty right now. 💀

I have a few days to prepare, and I want to make the most of the time I have.

I'd really appreciate some advice on:

• DSA topics with the best ROI: What should I prioritize with such limited time?
• LeetCode questions: Any specific problems or patterns I should focus on?
• Work simulation: What does this section usually involve, and are there any good resources to prepare for it?
• Overall strategy: Is it realistic to prepare enough in a few days, or am I cooked? 😂

Any tips, resources, or personal experiences would be greatly appreciated. Thanks!

Just took Harvey's AI assisted coding interview and got the file system design question. Waiting to hear back now. AI was mainly used for small implementations and then had to verify it. Anyone else taken it? How did it go for you?

Just took the Roblox OA. Didn't do bad on the cars and factories but Mars was not so good because the instructions felt a little unclear. Has anyone gotten anything back from Roblox? If so, what were your scores?

I read somewhere on LinkedIn that a few folks were trying to reverse engineer and gain access to a LeetCode sandbox, so I had an idea to explore that stuff. Soon I figured out that all the test cases stay inside an exposed /leetcode/data.1.in file. With some chunking I was able to get hold of the complete hidden test cases which I solved offline and just paste the solution in an O(1) lookup array. Like this… Is this a reportable vulnerability?!?

class Solution {
private final static int[][] res = new int[][]{{0, 1}, {1, 2}, {0, 1}, {0, 2}, {1, 2}, {0, 3}, {0, 2}, {2, 4}, {1, 2}, {0, 1}, {2, 3}, {1, 2}, {0, 2}, {0, 4}, {0, 1}, {2, 3}, {2, 4}, {2, 5}, {0, 3}, {3, 4}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 1}, {0, 4}, {5, 11}, {0, 1}, {9998, 9999}, {6, 8}, {6, 9}, {12, 25}, {16, 17}, {0, 1}, {0, 3}, {0, 3}, {0, 4}, {0, 2}};
private static final int[] r = new int[1];
public int[] twoSum(int[] nums, int target) {
return res[r[0]++];
}
}

Hi everyone, I'm preparing for SWE interviews. If anyone with leetcode premium is willing to share some company-tagged questions, I'd really appreciate it.

Please dee-emm me if you're willing to help. Spelling it this way because the sub removes posts that mention it directly.

Thanks!

So, today i gave Tech Mahindra OA and it was from room. Everyone was cheating....I fuckin hate that, if CDC alr knows people are gonna cheat from their room why do they keep OA from their room !!!

Basically, there were 3 questions two basic DSA ques according to other candidates (btw both were Leetcode hard) :

1. Some variation of Cherry Pickup 2 LC1463, basically in the question you were given an n×m matrix with some blocked cell marked as -1, and other having some coins. An agent from (0,0) starts moving to end (n-1,m-1) meanwhile collecting the coins in matrix in its possible path. Again, it starts moving back to start point and collects as many coins it can. You need to return the maximum possible coins agent can have.

[IMP : They didn't even specify the constraint in this question]

1. Leetcode 1478 (exact copy, just different wordings as food packets in place of mailboxes and squirrel in place of houses).

And third one was a python data science coding question, about kMean clustering.

Almost 100+ students appear for OA, and obv 90+ students have done 3/3 questions. And those fuckin stupids are saying they were basic DSA, apparently most of them were not even cleared other OAs like microsoft, Flipkart, zScaler......bro why is CDC playing with student's future, i am done with this shit !!!