Hi everyone,

I recently appeared for the Cisco Technical Intern 2027 on-campus online assessment through my university recruiting process in the US. Sharing my experience for anyone preparing.

MCQs and Subjective Section

The theoretical section was more technical than I expected.

Topics included:

• Operating Systems
• Computer Networks
• Object-Oriented Programming
• Computer Architecture
• C/C++ fundamentals

The subjective section was not just short factual answers. Most questions required proper technical explanations, so they took considerably more time than typical MCQs.

Coding Round

There were 2 implementation-focused coding problems. The coding section was challenging mainly because of the time pressure. With 42 total questions, you have to move quickly and avoid getting stuck too long on any one section.

Both problems were solid DSA/data-structure questions, and the expected style was closer to clean C++ implementation using structs/classes rather than just plain functions and arrays.

Coding Question 1: Implement an LFU Cache

Related Cisco practice problem: Implement an LFU Cache

The task was to design a cache that supports get and put operations while evicting the least frequently used key when capacity is full.

If multiple keys have the same frequency, the least recently used key among them should be evicted.

Core idea:

• Use a hashmap for key to node/value lookup
• Track frequencies separately
• Maintain ordering within each frequency bucket
• Keep track of the current minimum frequency
• Make both get and put efficient

This was not too bad conceptually, but the implementation details can get messy under time pressure.

Coding Question 2: Solve max-subarray, min-unique, and grid-jump

Related Cisco practice problem: Solve max-subarray, min-unique, and grid-jump

This was a multi-part implementation-style problem. It tested whether you could quickly recognize common patterns and code them cleanly.

The parts were around:

• Finding a maximum subarray with indices
• Handling uniqueness/minimization logic
• Solving a grid-jump style traversal problem

Core idea:

• Kadane-style logic for the max subarray part
• Hashing/frequency tracking for uniqueness constraints
• BFS/graph traversal thinking for the grid component

The tricky part was not that each subproblem was impossible, but that the combined format required speed, clean structuring, and careful edge-case handling.

Difficulty

MCQs: Medium
Subjective: Medium-Hard, mainly due to length and technical depth
Coding: Medium-Hard

The biggest challenge was time management. The coding questions were manageable if you recognized the patterns quickly, but the subjective section consumed more time than expected.

Preparation Tips

• Revise OS, CN, OOP, Computer Architecture, and C/C++ fundamentals
• Practice cache/data-structure design problems like LRU/LFU
• Practice Kadane’s Algorithm and array implementation problems
• Practice BFS/grid traversal problems with edge cases
• Be comfortable writing clean C++ code using structs/classes
• Take mock OAs under strict time limits

Overall, the OA felt very implementation-heavy and CS-fundamentals-heavy. I would recommend balancing DSA practice with theory revision instead of preparing only LeetCode-style coding problems.

Hope this helps anyone preparing for Cisco Technical Intern 2027.

I’m working on a traffic generator to test my own XDP/eBPF filter in a controlled lab environment (my PC sending traffic to my Raspberry Pi on my own network).

I noticed that in some applications, two programs written in the same language can have vastly different performance.

For example, some software can only send a few requests/messages per second, while others can generate thousands per second even on relatively weak hardware.

What is this concept or optimization area called?
I’m looking for topics such as:
asynchronous I/O
multithreading vs event-driven architectures
lock-free programming
kernel bypass
zero-copy networking
batching
efficient socket APIs
packet generation optimization

If I want to build a high-performance TCP/UDP packet generator for benchmarking my own network stack and XDP filter, what technologies, algorithms, or papers should I study? For traffic generator i am using c# and for the XDP filter classic C. ( or should i use different for the traffic generator? I think its okey its console app )

I’m working on a traffic generator to test my own XDP/eBPF filter in a controlled lab environment (my PC sending traffic to my Raspberry Pi on my own network).

I noticed that in some applications, two programs written in the same language can have vastly different performance.

For example, some software can only send a few requests/messages per second, while others can generate thousands per second even on relatively weak hardware.

What is this concept or optimization area called?
I’m looking for topics such as:
asynchronous I/O
multithreading vs event-driven architectures
lock-free programming
kernel bypass
zero-copy networking
batching
efficient socket APIs
packet generation optimization

If I want to build a high-performance TCP/UDP packet generator for benchmarking my own network stack and XDP filter, what technologies, algorithms, or papers should I study? For traffic generator i am using c# and for the XDP filter classic C. ( or should i use different for the traffic generator? I think its okey its console app )

Hi everyone, I'm currently a sophomore Computer Science student, and lately I've been feeling like I've fallen far behind. I passed my introductory programming courses Python, C, C++, Java/OOP but over time I feel like I've forgotten almost everything because I rarely used those concepts consistently. One thing I've realized about myself is that I learn best with routine and structure. I don't do well jumping between random YouTube videos or constantly changing resources. I'd much rather have one high quality source for a topic, study it consistently every day, solve exercises, and gradually build my understanding.

So I have a few questions:

If you could start over as a sophomore, how would you rebuild your CS fundamentals?

What would your roadmap look like over the next 1 year of dense study?

What resources books, courses, websites would you choose for DSA, Operating Systems Computer Networks Computer Architecture Databases Linux Cybersecurity (just enough to understand the field before specializing).

How do you deal with forgetting? I constantly feel like I learn something, then months later I can't remember enough to use it confidently. Is this normal? How do experienced engineers retain knowledge without trying to memorize everything?

Is it realistic. or even useful, to aim for a broad understanding of all the major CS areas before specializing? Or should I focus deeply on one area much earlier?

I see NeetCode recommended everywhere, but it seems heavily focused on coding interviews and LeetCode. Is that actually a good place to build CS fundamentals, or is it mainly interview preparation? Should I first study algorithms from a textbook/course before using NeetCode?

If you've ever felt behind and successfully caught up, I'd really appreciate hearing what worked for you. I'm especially interested in advice from people who felt "late" compared to their peers but eventually became competent engineers.

Thanks in advance.

This is a piece of code I found while refactoring our insanely complex drag-and-drop component canvas that already went through several refactors for performance optimization in the past:

function refreshShape(shapeId: number) {
return shapeId;
};

I'm not even kidding. My teammate and I laughed so hard. It was probably written by someone at some point to do something and either got distracted or was multitasking. This was before LLMs were being integrated in our workflows.

Hi everyone,

Over the past few months, we've been building TadreebLMS, an open-source Learning Management System focused on enterprise and corporate training.

We've recently completed a major restructuring of the project

How can we use AI in our product and process to speedup the development, process and customer support ?

The project is built with:

• PHP / Laravel
• MySQL
• Bootstrap / JavaScript
• Docker

GitHub:
https://github.com/Tadreeb-LMS/tadreeblms

Issues:
https://github.com/Tadreeb-LMS/tadreeblms/issues

We have a huge roadmap like SCRUM Integration, UI upgrade as per FIGMA, Gap Analysis Module Integration, Integrations with HR Systems etc...

Please anyone experience or architect in PHP can give recommendation on best practices, gaps in the system etc..

While doing a lot of vibe coding( not straight vibe coding, but spec driven-architecturally designed) and building full fledged application hosted on AWS and publishing to playstore, I generated an interest in agent memory and then built something around the memory, but still I wasn't convinced with the way coding agents explores the codebase by ripgrep or get-content.

So, I went deep into data science - basically graph database, gremlin, GraphSAge, A*, and many other. The thing I noticed was that " A model doesn't know what it doesn't know".

Which means, a function might have been changed or updated for 100 times, and each change carries some info, coupling, architectural descions(few times), and many such. But the agents at the time of exploring it sees the function as a static image without any layers beneath it. Sometime it might do - git diff but, a function being designed in that way carries a huge coupling with other functions over different commits. The agent barely figures out these relationships and concludes its descions merely on calls, imports, indexing of the other functions, docs, git log... But a developer trying to fix or update to accomodate a newer update, it first understands what and why of class, file, functions and related then updates.

This is why, Agents prefer on building a completely new functions, methods rather than just updating a small change in the same function.( the reason behind is that, an agent doesn't know that it doesn't know). Yes, I read github repo - ponytail which tells similar but it is mostly a smart prompting to compell the agents to grill before writing.

But, what if we provide the exact info that it misses, what if we provide, which functions are structurally similar, what if we traverse from commit -follow the edge(might be descions, update, fix, or such) land to some function states of those functions, understand them, traverse to that function, understand the clusters of those functions, read which functions are co-changed with that particular on which specific problem - then traverse the vector aided traversal with the edges leading to other functions... and so on.

I mean yes I am talking about embeddings of nodes, edges on some graph database and providing tools to the agent to explore the codebase, not only exploring, grill the codebase, understand the each bit of things before concluding any descions and recursively traverse between interconnected nodes with the help of multi-weighted edge between nodes.

I know 30% of the graph data should be populated by LLMs, but these can be done by any lightweight models or even self hosted ollama models on 16GB VRAM Mac or so.

If it sounds any good, then I have been building and had been testing for past 2 months, and results are way more efficient and effective. Token consumption literally reduced by 5x and effectiveness is still not as good as it should be because models are trained to use the cli commands, but working on that as it needs more depth knowledge of data science.

I reallly need you guys to put me on right boat if you have any things to say, grill, the comment section is all yours. - Pardon for my English

Hello! I just started Programming like 4 months ago and yes i started from web development, learned how to program in js and typically in html and css too did some normal and easy projects because i really didn't like Designing at all still i don't like designing. I started Programming in Python and after getting to know what "OOPS" is, i did write some programs using the stuffs i learned before. I was really interested in C++ and i started programming in C++, it was so fun and i did learn till some STL ( Standard Template Library ) of C++ then my friend suggested me to continue back on python as its mostly used right now, its easy, used in variety of tasks. I am back in python learning the use of some libraries and hosting backend on FLask. I am doing these but dont know what do i do now. Can anyone give me some advice, i would love to hear all of your guys Opinion.

I have a couple files on my computer that are dedicated to documenting CLC INTERCAL. Some of those are HTML files, and grouped with those files are a couple HGEN files. I've never heard of them, but from it looks like it's just HTML with a couple of slightly strange additions.

I'm guessing it works a bit like the C preprocessor, and probably references some other docs. Very strange.

Here is a snippet of the parsers.hgen file that illustrates what's weird about them. I just want to be able to properly read it.

    In addition to registers and constants, the following are valid expressions:
    <UL>
@@MULTI EXPRESSIONS NAME@@
        <LI><A NAME="op@@NAME@@">@@NAME@@ - @@DESCR@@</A><BR>
        @@DOC 76 HTML@@
@@MULTI@@
    </UL>
    </P>

    <H3>Statements</H3>

    <P>
    The following opcodes are valid statements:
    <UL>
@@MULTI STATEMENTS NAME@@
        <LI><A NAME="op@@NAME@@">@@NAME@@ - @@DESCR@@</A><BR>
        @@DOC 76 HTML@@
@@MULTI@@
    </UL>
    </P> 

Heyy all, I've recently started learning programming and I've already covered the basics and I think I'm now ready to start learning my first language properly. I have a very little tiny background on C and python because I took some courses a while ago but ended up not finishing them.

I ha've asked some people for advise, some said you should start with C++ to have a good foundation and it makes it easier later to learn new languages, while others said you should start with JavaScript because its faster and easier to learn. And I'm completely lost now.

Also, I'm starting my high school senior year in September so I'll need to balance school with learning to code so I can't 100% focus on coding. And I'm also still lost in what field I want to get into but Ai and web development seem pretty interesting to me. I don't want to start with something and ending up not finishing and regretting it like what I did a while ago.

So my question is what would you do in my situation?

Thanksss!!

i dont really know anyone else more "experienced" than me to talk in person about this, but basically is using AI´s / LLM´s to learn bad? on my college course i use claude/gemini to teach me some things, like concepts, error messages etc.

lately i´ve been thinking that by doing that im not really "learning" in the sense that without AI i´d likely spend hours or even days trying to figure out a problem and then i would learn it? i think that makes sense but i could likely be wrong. What i want to know is if im right or wrong and what i should do about it

Basic project to learn more about Linux system calls and C programming. I accept any criticism.

Im someone who made a program that disables the enhance precision pointer when you play league of legends and when the league closes it turns back on this thing i want to sell it for 1-2 euro but i want someone who can teach me how to sell it i know is small but a lot of people complaining about this on lol community is anti cheat free doesnt inject to anything how i can make this happen i dont want to be milionaire but i think is a smart idea please dont laugh at me

By the time I graduated in December 2025, I'd already been laid off from my brand new IT job in September. I never got a chance to do an internship because I was working full time in food sales and then IT for food sales. I spent time building projects while laid off, but I did also take some time to travel, put some energy into my music, work on my Spanish, and other things I haven't had time to do in years, so it's not like I've had a straight 7 months of coding and interview prep (far from it).

I'm good enough at leetcode and my projects are good enough that I could've probably landed a job *somewhere* in 2019, but it seems like to stand out now, I'm going to need much bigger and better projects, which could take me months from now still (and maybe people will just assume I vibe-coded it anyway). So far I've made a Chinese learning app (vibe-coded), and a faux-social media app (mostly coded by my own fingers, though with some help from AI). They're solid as beginner projects, but they're not "MIT material" yet imo if that makes sense. Which is significant to me, because it's those 22 year old kids from MIT with 3 internships and very flashy projects who are posting about not getting jobs. They are who I'm in competition with. I suppose I need to be on their level and then some, but I'm not even sure if that's realistic on the current timeline.

I'm not sure how long it's going to take to finally get into a company, and I'm not sure at what point I should just accept the sunk cost... I recognize that I'm doing a lot of unpaid learning right now, which is fun, but also feels like a waste of time if I'm simply barking up the wrong tree as the ladder gets pulled up, and I should be focusing my energy on working at this point, since I'm running out of money. Fun is something you can do when you already have money coming in imo.

I'm increasingly relying on AI to make flashier looking projects quickly and make myself look more prolific, and because many job descriptions actually want you to use AI tools. There's also this pressure to demonstrate the use of so many technologies even as a beginner, as if you've been in the business for a few years. While I'm sure other employers view AI as a huge red flag, it could go extreme in either direction depending on what the actual person hiring thinks about AI. It's hard to predict, and I'm not curating my website for individual jobs, it's just one website.

It's starting to make me think that this path might be so difficult, that it's actually on par with some of my "stupid ideas" like being a famous musician, or a youtuber or something. And in that case, it seems like I need to come "back to earth" and pick a completely different path besides SWE... Which is tough. Back to the drawing board yet again after trying to fight my way in for so long.

We’re building Extra, an open-source AI agent framework, and we’re looking for contributors.
If you enjoy solving hard engineering problems, we’d love to have you.
We care about code quality. Every PR gets a real review—not just a quick approval. We discuss architecture, challenge design decisions, and aim to keep the codebase something we’re proud of.
We’re working on problems around AI agents, orchestration, MCP, memory, approvals, and developer experience.
If you’re looking for an open-source project where you’ll actually learn from reviews and work on modern AI infrastructure, check out the issues and pick one.
Contributions of all sizes are welcome.

Basic project to learn more about Linux system calls and C programming. I accept any criticism.

I want to learn something related to Computers and AI, or something like that. But there are too many things popping up in my head (Backend, Frontend, Full-stack, Cybersecurity, AI, and of course the coding languages, plus a bunch of open-source things on GitHub (I don't even know how to use it, lol)), and I don't know which one I should start with first.

The problem in my head is:

I value traditional coding, because it gives me the mindset about the way algorithms work. But if that's all I do, it's not enough, because still from my mind, I still need to do the quizzes or sth like that. And if I just use AI for vibecoding, then maybe I won't understand the system.

FAQ: What do you want to do in the future?

• My target is Mechanic, but I still want to stay informed about coding and AI stuff.

FAQ: Then if you know the problem, what will you do next?

• I know that I'm supposed to move into the unknown first, even if I don't understand where it leads. Maybe I'll download some cool open-source code, look at all the components, and try to understand them — draw out the system. And from all the components, I'll see if I can change them, and why I can't.

Hello, yes i know this question has been asked thousand times and its gonna get asked thousand times more, but i just want to know if its still worth trying to get in?

Im from EU but not a developed country... Im in my early 20s and i've been seeing all this news about companies laying off experienced developers cuz of AI...

Since i started a normal 9-5 job at 18, my paycheck was never enough, i had to help my family and i just never thought of my future untill now... I just feel stuck and i dont know how long can i stay at minimum wage 9-5 job....

I would lie if i said that i was always passionate about coding, no, but i cant see myself anywhere else...

Lastly ive seen and read tons of post in this community about same topic but im still 50/50.
Idk what im looking for after this post goes through but hopefully i will find something....

Edit: I've little beginner experience, so ik how AI works and how it makes mistakes and it needs someone to check the code(so far), but i still dont understand will it replace humans or the paychecks will decrease in a long term...

where should i start if i want to learn coding?

I'm finding it really hard to write code. While loops are especially confusing I don't know when to use them or how to decide what condition to write. I'm also struggling to build logical thinking for programming. Do you guys have any suggestions on what I should do to improve

And I fixed my target to learn java completely in 20 days

You know, I recently discussed the topic “How to Code on Your Own” or rather, how to actually learn to program without AI in this thread. I tried everything people recommended. And nothing… I don’t know if I’m just a nutcase, since I tried all those methods in a single month. And yet, I still can’t program. I’ve always enjoyed the whole learning process of the IT world problem-solving is also incredibly fun but unfortunately, one thing is holding me back here… programming. And no, it’s not because I wouldn’t enjoy it, but most likely because I just don’t have the IQ for it.

I’m pretty creative when it comes to front-end development it’s my passion and I understand some of the concepts behind back-end development too, but when it comes to programming my own algorithms from scratch, it’s just a huge gap. I don’t know what to blame I blame my brain and my IQ. Unfortunately, I was born with developmental dysphasia. A lot of people say it only affects my ability to express myself, but there are many types, and I think it also affects part of my prefrontal cortex. Which, in part, doesn’t quite fit with the fact that I’m pretty good at memorizing patterns pattern recognition. I recall a lot of things from school based on visual patterns. I can go into my head and literally create a mental image of the object, and then I just write it down. I simply think that, unfortunately, I’m an idiot. I used to have big goals and visions, and I looked forward to contributing to society in some way. Now, the most I can do is sit in a corner and wallow in depression over the fact that I’m a worthless person.

That’s also why I’ve been researching lately, using MIT and Harvard studies, to see if there’s any way I can somehow That’s also why I’ve been researching lately, using studies from MIT and Harvard, to see if I can somehow influence my brain before I turn 20 if I can generally improve it to a higher level of logical thinking when it comes to programming through daily learning. I enjoy everything so much it’s so fascinating. I think it’s great to contribute to humanity through open-source projects, technology, and rocket engineering… Unfortunately, programming (or maybe my intelligence is holding me back, I guess) just doesn’t come naturally to me. I can’t write code, or I write something absolutely terrible, or I don’t know where to start, so AI has to help me. Why? Because I’m probably just an incompetent idiot.

It’s not self-pity I just wanted to vent. I don’t know what to do. My parents are worried about me, too, just because sometimes I struggle with abstract things in practical life. For example… I was supposed to unfold a cardboard box lengthwise, but I unfolded it widthwise because I just couldn’t picture the result at that moment I don’t know. What should I do? Will I end up on the street? Sure, my parents are rich I don’t need anything. But I’d hate to do nothing, not be independent, and not contribute. It’s awful.

I don’t know if it’s actually possible to train my brain through daily study to a level where I could program normally or do rocket engineering in the future I really don’t know. And it makes me sad that this is blocking me from my dream career.

And not to program? In IT? I can’t afford that look at the job market: people are fighting over only the very best, and the rest are either discarded, given a totally crappy salary, or not hired at all.

Obviously, I’m just going to be a disappointment because I don’t even want to do anything else this is a world that fulfills me so much, and programming is ruining it, most likely because of my intelligence. It’s a shame I can’t have a family and be self-sufficient I just don’t know. It’s a shame my parents can’t be proud of me for having gone far in my career. But with this GPA, I won’t get anywhere these days.

I am cooked. Just one thing.. HOW TO CODE IF I KNOW WHAT I NEED TO CODE. AND KNOW THE LOGIC IN PSEUDOCODE BUT STILL CANT TRANSLATE TO THE CODE.

thanks for listening and sorry.
I love my life I have a great family and close friends but this just pisses me off because I want to pour my heart and soul into my career; it’s practically the whole point of my life. Sort of. And it bugs me when I can’t be really good at what I do, even when I give it my all.

And most importantly, a lot of people say, “Try Haskell or Lisp to learn it,” but my friend, who’s the same age, programs without all that extra stuff… I guess people just show us these methods to reassure us—the less skilled ones who aren’t cut out for it. I don’t know people don’t like to admit things they can’t change.

I cant just do this: public static void InPlaceMergeSort(int[] arr)
{
int n = arr.Length;
for (int size = 1; size < n; size <<= 1)
{
for (int left = 0; left < n - size; left += size << 1)
{
int mid = left + size - 1;
int right = Math.Min(left + (size << 1) - 1, n - 1);
int i = left;
int j = mid + 1;

while (i <= mid && j <= right)
{
if (arr[i] <= arr[j])
{
i++;
}
else
{
int value = arr[j];
int index = j;
while (index != i)
{
arr[index] = arr[index - 1];
index--;
}
arr[i] = value;
i++;
mid++;
j++;
}
}
}
}
}