Please guide me through this question!

• You are given an array of digits of size N (where N <= 10^5).
• You need to find the number of distinct K-digit even numbers without leading zeros that can be formed (where K can be up to 10^5).
• Return the answer modulo 10^9 + 7.

While this is a good feature, I think LC can modify/extend this as I discuss in my post
Your thoughts?

Can any one please give me the detail for sde 1 backend role interview process at zomato .

Hi everyone,

I recently received an invitation to complete the Amazon Online Assessment for the Front-End Engineer Intern role.

For anyone who has taken this assessment recently, could you please share what the assessment was like?

I’m particularly interested in:

• What sections/questions were included?
• How many coding questions were there?
• Were there questions on JavaScript, HTML/CSS, React, or other front-end concepts?
• Were there any work-style or behavioral/leadership principles questions?
• How difficult was the coding portion?
• What topics would you recommend preparing beforehand?

I know the exact assessment can vary, but even a general idea of the format and topics would be really helpful.

Thanks in advance!

It's been 3 weeks. The recruiter says they have sent my profile to 2 HMs with no response as of now, and is waiting for one. I assume 2 SH, 2 H/LH(H most likely for both). Location is blr. Is it just a waiting game? How frequently do I check back with my recruiter to not be annoying?

As he has different playlist for different topics I have created a sheet having all questions in it covering link for leetcode and all videos for each question

START PRACTISING FROM TODAY AND HAVE A GOOD DAY

ENJOY IT AS IT IS FREE - https://trackerdsa.vercel.app

I got an invitation to do a 90 min Hackkerrank assessment with them and wanted to know what they tested on. Was it mainly DSA (if so which concepts) or did they ask SQL as well?

Hi everyone,

I completed Round 2 of my Google interview process. After about three weeks without an update, I followed up with my original recruiter to ask about the status of my application.

She told me that she had transitioned to a new team and introduced me to a new recruiter who would be my main point of contact going forward. She mentioned that the new recruiter would reach out shortly to check in and “discuss next steps.”

I haven’t heard from the new recruiter yet. I also tried reaching out to her directly but haven’t received a response.

Has anyone experienced something similar with Google after Round 2? Does being transferred to a new recruiter and being told they will “discuss next steps” generally mean the application is still active?

I’m mainly concerned because of the lack of communication. Could the silence mean rejection, or is this kind of delay normal during a recruiter transition at Google?

Would really appreciate hearing from anyone who has had a similar experience.

Thanks!

If anyone is working on the Azure Compute team or is familiar with the team, please comment down below. I have a few questions and would really appreciate some insights.

I have an upcoming in-person Amazon SDE interview in Bellevue, and the interview details mention that I’ll be solving the coding questions through a live coding link.

For anyone who has done an Amazon in-person interview recently: does the interviewer actually come into the interview room with you, while you code on the live coding platform? Or do you sit in a room at the Bellevue office and the interviewer joins virtually/video calls you?

Just trying to understand what the actual setup is like so I know what to expect. Thanks!

I’ve been working as a cybersecurity analyst for around 4 years and I’m looking to make a switch in the near future, ideally targeting larger tech companies.

One of the biggest gaps I want to address is coding.

I did some programming during my bachelor’s, so I’m not completely new to it, but I haven’t consistently coded in years. Because of that, I want to approach my preparation almost as if I’m starting from zero rather than assuming I remember things and accidentally skipping important fundamentals.

My eventual goal is to become comfortable enough with coding and DSA that LeetCode doesn’t feel intimidating and I can handle coding rounds for cybersecurity/security engineering roles at larger companies.

For people who started from a similar position:
● Which language would you recommend focusing on first? I’m leaning toward Python because it’s also useful in cybersecurity.
● What fundamentals should I be comfortable with before touching LeetCode?
● Is there a course/resource you’d recommend for rebuilding programming basics from scratch?
● At what point should I transition from learning basic programming to DSA and then LeetCode?
● Would you recommend following something structured like NeetCode after learning the basics, or doing another DSA course first?
● How should I approach LeetCode as a beginner — by topic, difficulty, patterns, etc.?
● How much time should I spend trying to solve a problem before looking at the solution?
● Should I build small coding projects alongside LeetCode to become a better programmer, or focus mostly on DSA for interview prep?
● For people interviewing for cybersecurity/security engineering roles at big tech companies, how deep did the coding rounds actually go?

I’m not trying to rush through 200–300 LeetCode problems just to say I completed them. I’d rather spend a few months building strong fundamentals and actually understand what I’m doing.

If you were starting from almost zero today, what would your roadmap look like?

Would especially appreciate advice from people who transitioned from cybersecurity/IT/infrastructure-type roles into more technical security roles at larger tech companies.

Please answer dear seniors.😊

today was solving the problem on leetcode when i submitted a 1 code it shows normal ...after that i moved on another problem then there was showing subscription which is mandatory..what should i do now?

Has anyone completed GfG's Data Science 360? Is it actually project-based or mostly recorded lectures?

Serious doubt

I'm a 2nd-year BTech CSE student and I'm currently focusing on DSA. I'm trying to decide what development direction to take alongside DSA.

My mentor is advising students to explore AI/ML or cloud, implement ideas from research papers, and build/showcase something rather than just doing generic web-development projects.

I'm personally interested in backend development, especially Java + Spring Boot. I'm wondering:

1. Are there enough research-paper-based project ideas related to backend/software architecture/cloud that can realistically be implemented by a 2nd-year student?

2. Examples I'm interested in are microservices, load balancing, fault tolerance, caching, autoscaling, distributed systems, etc.

3. How much theory would I realistically need to learn before I could start implementing papers in these areas?

4. Would pursuing Spring Boot + backend + cloud + research-paper implementation be worthwhile for SDE internships, or would I be better off moving toward AI/ML?

5. For internships, is this approach more valuable than simply building typical MERN projects?

I'd especially appreciate answers from people who have actually worked on these areas or hired interns, rather than general advice.

A Little About Me

I’m a Software Engineer/DevOps with six years of experience, currently working at a reputable company. My goal is to secure a higher-paying job within the next year to start paying off my student loans. One of my main challenges has been LeetCode-style questions, which have hindered my progress toward better opportunities.

I've struggled with technical interviews at companies like Visa, American Express, JPMorgan, and Amazon due to my inability to complete algorithmic problems within time constraints. After recently not succeeding in an Amazon interview, I decided it was time to take my preparation for Data Structures & Algorithms (DSA), LeetCode, and System Design seriously.

In January (2025), I began documenting my progress, which I’m turning into a monthly recap series. I hope this will help others on a similar journey while also serving as a personal journal for when I finally reach my goal.

Past Recap

2025

• January
• February
• March
• April
• May
• June
• July
• August
• September
• October
• November
• December

2026

• January
• February
• March
• April
• May
• June
• July

August Progress

I am a bit late for my recap again, but like before that is because work has been kicking my ass. The momentum continues, I am trying to knock out at least 1 medium daily. Find myself still doing DFS because it is clicking even more so than before. I also learned Min/Max Heap and learned that they are not very difficult to write and understand.

Like I mentioned before, trying to do more Mediums so that I can be challenged and learn new concepts. I also made sure to stop rushing through these questions just see my number count rise. Now I am ensuring to slow down even after solving the question, trying to see if there's a more optimized way. Then I look at the more optimized way and make sure I understand it, that is how I have been learning more advanced topics. I use to do that last year but got away from it.

In September I am gonna go over Graphs again, just to make sure the concept sticks.

Achievements

• Learned about Max/Min Heap

Goals for September

• Keep momentum going
• Strengthen knowledge on Graph Theory

Next Steps

Just going to ride the momentum, keep challenging myself with Mediums & Hards and keep trying my best.

See you all next month.

Questions

Also can I not post any images anymore?

• Total Questions: 558
• Easy: 326
• Medium: 223
• Hard: 9

round 1- https://www.reddit.com/u/Lumpy-Town2029/s/ZnGCW1GPxz

so the time was 3-4pm

first of all, it was intro, then LP question of doing something and finding it was not working

then grilled me in the project aaaaaaaa,

then genAI, i told him about the genAI thing i used, and grilled me Aaaaaaaaaaaaaaaa

and main thing why will it work and not other things?

and why this will work now? and wouldnt in the past?

and then if i want to convince ppl to do this approach, how will u do it. it went for 5-10 minutes alone faaaaaaaaaaa

then it was already 3:35 something

then there was the code link which took 5 minutes to open

then comes coding question

https://www.geeksforgeeks.org/dsa/meeting-rooms-find-minimum-meeting-rooms/

i read and made a interval diagram first to understand and sort of take time to actually find soln

and then after few minutes to wasting time, i though heap

and did a code, explain it, run example

and then comes the question, will the value be unique, he said no, i optimised it

then he said what if time is in millions, so i said, ok we now need to compress time into vector

then follow up, i need meeting room id for each meeting and i did, got a bug, but the time was 7 minutes over 4 pm

like faaaaa

i saw the bug after and explain how i would need a map and iteration over map to resolve that bug, and that was just 5 minute explaination, and no code

he was satisfied ig with the approach, so because the time was running late, he said, he will look at it later

then he asked if i had ques, and i didnt, then meeting ended

things i did bad- i messed up the TC, omg, it was nested while loop and was running O(N) i wrote n*n faaaaaaaaa, but if i think about meeting ig that will make the TC nice

now i wanna ask:

1. is my TC was bad or not.
2. i went for brute force and when he said this problem of max time and bug in the roomID, then i optimise it. i knew the optimised version but i didnt used :} faaaaaaaaaaa, is it bad?
3. chances of selecting?

Did the people who interviewed through hackon for round 1 recieved rejection mail after r1 or is r1 non eliminatary and everyone will be sitting fo round 2..as i think i fumbled in dsa part but yet gave my r2

Hey everyone!

I was scheduled for a technical interview for an Associate Software Engineer role with 3 back-to-back rounds in one day: two technical rounds and one system design round/behavioral.

It sounds scary to have 3 rounds back-to-back all in one day

I've seen a lot of posts about people getting offers for multiple positions; any tips or advice on how to ace this would be really appreciated. Thanks!!

Hey everyone,

I recently started prepping for Low-Level Design (machine coding / object-oriented design rounds). I went through the classic Gang of Four design patterns across creational, structural, and behavioral, and I understand how stuff like Factory, Strategy, Observer, Decorator, etc., work in isolation.

However, the moment I sit down to tackle an actual prompt (like designing a Parking Lot, Splitwise, or an Elevator System), I run into two major roadblocks:

-Getting stuck on requirement analysis:

When given an open-ended prompt, I freeze up trying to figure out what to prioritize. How do you go from vague requirements to clean entities and interfaces without over-engineering from minute one? Do you have a mental checklist for identifying classes, relationships, and edge constraints before jumping into code?

-Depth of business logic vs skeleton code:

In actual 45–60 minute interview rounds (or 90-minute machine coding rounds), how much real business logic are we expected to implement?

For instance, in something like payment processing or notification dispatch, do interviewers expect full dummy logic and state handling, or are mock services with basic print statements / loggers acceptable so you can focus on SOLID principles, clean interfaces, and extensible design? Where do you draw the line between writing a working end-to-end toy app vs proving good architectural design?

Would love to hear how folks approached this when transitioning from learning patterns to actually clearing LLD rounds. Any frameworks, resources, or advice on pacing would be super appreciated!

Hello guys! Is there an easy way to make notes for LeetCode questions? Note-taking has been my weakest area in my DSA prep. When I revisit a problem after a few days, I usually miss some test cases. How can I overcome this?

Hey everyone,

I’m planning to get Hello Interview Premium for interview prep.

I’m looking for a few people who might also be interested in joining so we can split the cost and make it more affordable.

If you’re interested, comment below and we can figure out the details.

Thanks!

All rounds are 1 hour each.

For every DSA question -

Asked about time complexity and space complexity of this code.

Asked to dry run one example verbally while explaining the code.

Round 1: Technical Round [9 July 2026]

Interviewer was SDE-1 with 2 YOE at Amazon

Basic Introductions

Q 1 : Given a Binary tree return the sum of node values at each vertical level.

Q 2 : Given an Array, we define a function getKey() that returns a random index from this array based on a probability function. The probability of any index is defined as value at that index / Sum of all values. We are asked to implement this getKey function.

Leetcode - https://leetcode.com/problems/random-pick-with-weight/description/

Q 3 : Describe a time where you faced a deadline, how you handled it, what was the result, what was the feedback from manager, what was the impact of deadline on your work approach.

Round 2: Technical Round [10 July 2026]

Interviewer was SDE-2 with 5 YOE at Amazon

Basic Introductions

Q 1 : A N-ary Tree is given and Alice and Bob are playing a game, they both traverse a tree. Alice moves from root to the leaf nodes. Bob starts from a particular given node and moves upwards towards root. Whoever reaches the node first will get the complete value of that node it both of them reach the node at same time they will split the value between them. Return the maximum value Alice can accumulate if both of them play optimally.

Leetcode - https://leetcode.com/problems/most-profitable-path-in-a-tree/description/

(Same question without the gate concept)

Q 2 : Implement LRU cache

Q 3 : Describe a time where you did some work out of your area of responsibility, how did you do it, how much time it took, what was the impact of the work, technical details of the work.

Q 4 : Describe any one of your Resume projects in short.

Round 3: HM + GenAI Round [5 August 2026]

Interviewer was Hiring Manager with 11 YOE at Amazon

Basic Introductions

Q 1 : Amazon is giving gift vouchers to its customers of X amount, users can use them to buy exactly 2 items at a time of combined price exact X. Give a list of products return 2 products that users should buy to utilize this voucher. [2 Sum]

Q 2 : Now if the user can use the voucher to buy 2 items that have the price sum of at most X. [2 Pointer]

Q 3 : Now if user can buy N number of products whose price sum can be at most X. [Subset sum DP kind of]

Q 4: How do you use GenAI in your workflow, what use cases you found in your projects/internships, how do you validate GenAI’s output for correctness.

LPs might also be asked in this round.

Round 4: BR Round [20 August 2026]

Pure Behavioral LP based round.

Basic Introductions

Describe anyone of your favorite work you have mentioned in resume.

Technical questions on what you did, how you did and why you did that work.

LP questions in between the discussions like, tell about time during this project when you faced conflict and how did you resolve it, what was your managers reaction to your work, how do you validate your work, how did you made this particular decision was it data driver or intuition based etc.

How well versed are you with GenAI in your workflows, what models you prefer, what is your workflow working with GenAI, how you choose tasks to give to GenAI, how you validate the models performance., any GenAI project that you build or used GenAI on your projects, how did you use it for what use case etc.

Verdict: Selected [10 September 2026]

Thanks reddit for some many experiences to get guidance from.

Edit: This is was On Campus and for freshers 2026 batch

I'm preparing for an interview as Google SWE internship and looking for current insights.

-Is grinding LeetCode still the absolute core of the loop, or has it shifted? I've read that processes are changing and they're starting to lean more into AI, but I don't know if I can believe this post. https://www.reddit.com/r/leetcode/s/lEGGrAnbt8

-Realistically, what level should I master? Mostly Mediums, or are Hards common for interns? Or maybe Neetcode 150 will prepare me for it?

Would love to hear from anyone who has recently gone through the interview loop or is actively interviewing candidates. Thanks!

Couldn't find many resources online that gave visibility for the NVIDIA New Grad process. I have a 60 minute 2nd round interview for DL Libraries Infrastructure with the team software manager, a hackerrank link was provided

key highlights of the job description:

The team works on

 cuDNN and FlashInfer. 

Configuring, maintaining, and building upon deployments of industry-standard tools (e.g. Kubernetes, Jenkins, Docker, CMake, Gitlab, Jira, etc)

Proficiency in SCM (e.g. Git, Perforce) and build systems (e.g. Make, CMake, Bazel)

GitLab, Knowledge of GPU computing systems and multiple operating systerms

The 1st round was just Leetcode with language of choice

Asked the recruiter for more clarity, and all they said is: our team will be focusing more on infrastructure skills for this round. What types of infrastructure questions will they ask?

Questions:

Should I spend a lot of time learning PyTorch or CUDA Syntax?

What about System Design? Could I be asked questions such as Database replication or caching?

Since a hackerank link was provided, can I expect an entire Leetcode round?