TL;DR: 2 months into DSA as a uni freshman. I can solve (80% of easy), but I hit a hard wall on Mediums (problems attached, was trying to do them yester day night) and always end up checking the solution( i HATE LOOKING AT THE SOLUTION AND GIVING UP). Is this normal? Looking for advice since I want to get into competitive programming.

I just started university and have been grinding DSA for about two months. While I can solve roughly 80% of Easy problems (mostly just troubleshooting edge cases), I get completely stuck on Mediums.

For example, I couldn't do the two problems I tried yesterday including the matrix spiral traversal in my screenshot. I can usually brainstorm different approaches, but I rarely find the right one and end up having to look at the solution, which I really hate doing.

Is hitting a wall like this normal at mediums? I want to build strong fundamentals for competitive programming, so any advice from experienced folks would be greatly appreciated!

Hey guys I started doing dsa and I am following strivers a2z sheet and I am having a really bad time implementing the actual code i use c++ even if i could write the pseudocode i still have trouble writing the actual code please give some advice on how can I improve it

So I just started my first semester. And I went through a lot of recommendations to start DSA.

So, how does this preparation for DSA starts. Like what we learn, is there any definite syllabus. Where do we get the course material from? How do we test... etc.

Your response would be helpful.

Thankyou :)

Hi a little about me, I have around 5 years of experience in tech and mostly working in service based MNC. So I was doing DSA at my clg time and in the initial days of my job, like after 2022 I just stopped doing DSA. I did a decent around 300 questions on different topics but everything seems difficult now.

Now I want to start it again and I feel a little lost as this whole AI thing has come so it feels like, is DSA even worth starting again or should I focus on something else. I am seeking some advice on what I should do now and if DSA is still relevant how to start again and how much time will it take because I want to leave this service based switching again and again.

I was able to switch my tech from a support role to Java developer in the first 2 years of my career and now have decent things to write on my resume, but still as the exp is increasing so is the level of interviews and along with all other things starting DSA seems impossible.

Hello everyone, are there any IT working professionals who can help me? I will share what I need in a direct message, so please take out some time and message me. Thank you!"

Hey everyone,

I'm a 2026 graduate, currently working full-time, and trying to transition into Software Engineering.

I've been struggling with DSA for quite some time now, and I genuinely need some advice from people who have been through this phase.

My DSA journey so far:

Like many others, I've started DSA multiple times, but somehow I always ended up stopping around arrays.

This year, I decided to take it seriously. I started around mid-May and managed to cover topics up to Trees by mid-August. Unfortunately, due to some personal circumstances, I discontinued my preparation.

Recently, I had a technical interview that made me realize how important DSA still is for cracking good software engineering roles, regardless of what people say online.

Now I want to restart properly, but this time with a sustainable strategy rather than repeating the same mistakes.

Here's my current plan:

Weekdays (Monday–Friday): 3 hours daily

\\- 1.5 hours: DSA lectures

\\- 1.5 hours: Problem-solving practice

Weekends (Saturday–Sunday): 4.5 hours daily

\\- 1.5 hours: Continue lectures

\\- 1 hour: Revise previously learned concepts

\\- 1 hour: Reattempt older problems

\\- 1.5 hours: Practice new questions

I'm currently following Rohit Negi bhaiya's Coder Army DSA lectures, and I genuinely enjoy his teaching style.

Here's where I'm struggling:

Whenever a new problem appears during a lecture, I pause the video and try solving it independently. If I get stuck, I resume the explanation, understand the solution, and continue.

But here's my biggest mistake: I rarely revisit older problems or lectures.

My mindset has always been to finish the lectures first and then start solving problems from LeetCode or a structured sheet.

I think this approach is hurting my retention and problem-solving ability.

I can often understand a solution when someone explains it, but coming up with that approach independently is a completely different challenge.

I'm also confused between Striver's A2Z DSA Sheet and NeetCode 150.

I've tried following Striver's sheet, but I somehow struggle to get into a proper flow with it.

I'm not sure whether I should:

\\- Follow Coder Army lectures alongside Striver's A2Z sheet.

\\- Complete the lectures and then start NeetCode 150.

\\- Use one sheet exclusively and focus on revision.

\\- Stop watching so many lectures and spend more time solving problems independently.

My goal:

I have around 4 months to prepare seriously for software engineering interviews while continuing my development and AI learning.

I'm not trying to become a competitive programming expert. I want to develop solid problem-solving skills, recognize common patterns, and confidently approach unseen interview questions.

Questions for people who have successfully learned

DSA:

1. How did you balance lectures and actual problem-solving?

2. How do you revise older questions without forgetting previously covered topics?

3. Should I follow Striver A2Z or NeetCode 150 alongside Coder Army?

4. How much time should I struggle with a problem before looking at hints or solutions?

5. Is restarting from scratch a good idea, or should I revise what I've already covered and continue?

I know consistency is ultimately my responsibility, and I'm ready to put in the hours. I just want to make sure I'm spending those hours effectively.

Would genuinely appreciate advice from people who have faced similar struggles and eventually

improved.

Thanks in advance!

Setting node = nil inside a recursive call deletes nothing. The caller never sees it. A node can't remove itself because it has no reference to its parent.

A node survives if its subtree holds a 1 anywhere, which, recursively, is almost the definition read aloud. Post-order, because a node can't answer that on the way down.

So the child reports "nothing worth keeping here", and the parent clears the pointer. That leaves the root, which has no parent, and that's the only reason the wrapper function exists.

Have you ever nilled a local variable and expected the caller to notice?

Day 73/365 of my LeetCode challenge: 814. Binary Tree Pruning. Problem link and full breakdown in today's newsletter.

https://www.linkedin.com/pulse/leetcode-binary-tree-pruning-archit-agarwal-g6lsc

#LeetCode #DSA #BinaryTree #Golang

title

Hey everyone! Is anyone here using Leetcode Premium / Striver A2Z Plus and willing to share access so we can learn and practice DSA together?

I'm at an intermediate level in DSA and would be happy to help you with problem-solving, concepts, and discussions in return.

We can learn together and make the most of the subscription. Feel free to DM me. Thanks! 😊

Collecting every value and sorting works here, and it ignores a rule that hands you the minimum for free. Every node holds the smaller of its two children's values, so the root is always the global minimum.

That one rule does a lot of work. It also means you can skip a whole subtree as soon as you reach a value above the minimum, because nothing below it can be smaller.

One DFS pass, no collect-and-sort.

What's the strangest invariant a LeetCode tree has handed you?

Day 72/365 of my LeetCode challenge: 671. Second Minimum Node In a Binary Tree. Problem link and full breakdown in today's newsletter.

https://www.linkedin.com/pulse/leetcode-second-minimum-node-binary-tree-easy-archit-agarwal-eolmc

#LeetCode #DSA #BinaryTree #Golang

I am preparing for the infosys sp/dse in person coding assessment which is on Dec 6..and I want a guy to prepare seriously whose target is to crack l3..

Let's study together..dm me

Hi folks! About a year ago, I was in your place, struggling quite a bit with DSA. I was particularly weak at identifying patterns in problems, and on top of that, I couldn’t find enough questions to practise each pattern thoroughly.

To make things easier, I built [DSASheeeet](https://dsasheeeet.vercel.app/home), where you can practise almost every possible problem-solving pattern with a carefully curated set of problems to help you understand each topic inside out.

Apart from that, it also features 423 companies, so you can prepare for upcoming company assessments without spending hours researching questions. Whether you’re preparing for placements, planning a job switch, or struggling to identify patterns in DSA problems, DSASheeeet is here to make your life easier.

Check it out: [DSASheeeet](https://dsasheeeet.vercel.app/home)
No Auth Required.

Everything you need, all in one place!

The tree in this problem is a boolean expression with its parentheses drawn as branches. Leaves are True and False. Internal nodes are OR and AND, waiting on their two children.

Post-order recursion evaluates both children first, then the parent combines them. That's the same order you'd use to evaluate nested parentheses by hand.

Nothing fancy here. Get the order right, and the recursion does the rest.

Where else have you seen an expression stored as a tree?

Day 71/365 of my LeetCode challenge: 2331. Evaluate Boolean Binary Tree. Problem link and full breakdown in today's newsletter.

https://www.linkedin.com/pulse/leetcode-evaluate-boolean-binary-tree-archit-agarwal-ag7sc

#LeetCode #DSA #BinaryTree #Golang

My solution compares node values, and it only works because LeetCode promises they're unique. The follow-up allows repeated values, and then a value match can point to the wrong node.

The idea holds either way. cloned is a structurally identical copy of original, so there's nothing to search for independently. Walk both trees in lockstep with one recursive call, and the answer is waiting at the same position.

What changes for the follow-up is the test. Compare the original-side pointer with the target instead of comparing values, and duplicates stop mattering.

Would you have spotted the duplicate-values follow-up in an interview?

Day 69/365 of my LeetCode challenge: 1379. Find a Corresponding Node of a Binary Tree in a Clone of That Tree. Problem link and full breakdown in today's newsletter.

https://www.linkedin.com/pulse/find-corresponding-node-binary-tree-clone-archit-agarwal-dkvsc

#LeetCode #DSA #BinaryTree #Golang