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How to Find the Right View of a Binary Tree

Here's a mistake that's almost too easy to make: you've just solved left view of a binary tree, the interviewer nods and asks for right view next and since the two problems look so similar you reach for the same code, flip a comment or two and submit it. Except if you didn't actually flip the traversal direction , you've just handed back the left view a second time, dressed up as the answer to a different question. This article walks through exactly that trap and how to build a right vi

~ DevSniper

⏱️28 August 2026

Left View of a Binary Tree: DFS and BFS Approaches Explained

There's a specific kind of interview moment that catches a lot of people off guard: the interviewer asks for the left view of a binary tree, you write a solution that looks completely reasonable, run it mentally against the tree on the whiteboard... and it quietly returns the right view instead. Not a crash, not an obviously wrong answer just a plausible-looking list of numbers that happens to be exactly backwards. This article walks through why that mix-up happens so easily a

~ DevSniper

⏱️28 August 2026

Top View of a Binary Tree Using BFS and DFS | Complete Guide

If you've spent any time prepping for interviews at product-based companies, you've probably noticed that binary tree "view" problems top view, bottom view, left view, right view show up constantly. They look deceptively simple on a whiteboard, but the moment you start coding one under interview pressure, it's easy to write something that looks right, passes on the example the interviewer drew and then quietly falls apart on a slightly different tree shape. This article

~ DevSniper

⏱️28 August 2026

Python Interview Questions for Freshers

If you're getting ready for a Python interview as a fresher, you've probably already found a dozen pages listing the same 15-20 questions. This guide covers those, but goes further it's organized by topic, every code example was actually run to confirm the output shown is real (not just typed out and assumed correct) and a couple of explanations that are commonly gotten slightly wrong elsewhere have been written the accurate way here. I ran every single snippet in this guide t

~ Harshit Kapoor

⏱️27 August 2026

Sorting Algorithms Explained: A Complete Guide

Open any shopping app and sort products by "price: low to high." Open your email and sort by date. Open a spreadsheet and sort a column of names A to Z. You do this so often that it feels like a basic feature, almost too simple to think about. But behind that one click, some algorithm had to actually rearrange thousands, sometimes millions, of items into the right order, fast enough that you never notice it happening. That's what sorting algorithms actually are: step-by-step meth

~ Jack Wilson

⏱️27 August 2026

System Design Interview: How to Prevent Duplicate Payments Using Idempotency

You order food for ₹500 and tap Pay . The app spins for a second, then suddenly goes white and shows, “Something went wrong, please try again.” At the same time, your phone's network briefly dropped right when the payment was being processed. Now you're left with a simple decision: Do you tap Pay again? You probably do, because you don't want your food order to disappear. But the system on the other side has a much harder problem to solve: Did that first payment actually go through o

~ Rajat Chaturvedi

⏱️26 August 2026

Bottom View of a Binary Tree: DFS vs BFS Approach

You are given a binary tree. Imagine standing directly below it and looking straight up the bottom view is the set of nodes you'd actually be able to see. More formally: for every possible horizontal position in the tree, the bottom view keeps only the deepest node sitting at that position. Nodes that are hidden behind a deeper node at the same horizontal position don't make the cut. Given the root of a binary tree, return its bottom view as a list of values, ordered from left to rig

~ DevSniper

⏱️26 August 2026

Longest Playlist With No Repeated Songs : Brute Force to Optimal

You are given a user's listening history, where songs are stored in the order they were played: Song1, Song2, Song3, Song1, Song4, Song2 Your task is to find the longest possible playlist that can be created from this listening history. The playlist must follow these rules: The songs must remain in the same order as the user's listening history. The playlist must contain a continuous sequence of songs. You cannot skip any song. No song can be repeated within the playlist. Retu

~ DevSniper

⏱️25 August 2026

PostgreSQL Interview Questions: Fundamentals, Performance and Advanced Topics

Preparing for a PostgreSQL interview? This guide covers PostgreSQL interview questions from the basics to advanced database concepts, with simple explanations and practical examples. You’ll learn about SQL queries, PostgreSQL data types, constraints, indexes, joins, transactions, ACID properties, normalization, query optimization, execution plans, partitioning, concurrency, locks, stored procedures and performance tuning. The questions are explained i

~ Gaurav Bhasin

⏱️24 August 2026

Top SQL Interview Questions and Answers: A Complete Guide for Beginners

This guide covers the most common SQL interview questions , explained in simple language with practical examples you can actually run and understand. Instead of switching between unrelated datasets for every question, we’ll use the same small set of tables throughout the guide. This makes it easier to follow the queries and focus on understanding the SQL rather than figuring out a new schema every time. Sample Tables Used Throughout the Guide Students ID , FirstName , Last

~ Garima Puri

⏱️24 August 2026

My Adobe SDE Interview Experience (Aug 2026) 5 Rounds, Selected

I want to share my Adobe interview story. I will tell you what happened in each round, what I got right, where I got stuck and what the interviewer said to help me when I was stuck. I will also show the code for every DSA question, starting from my first (slow) idea and ending with the best idea. I hope this helps you if you have an Adobe interview coming up. Result: Selected. Detail Info Company Adobe Role SDE (Backend Developer) Total rounds 5 Coding problems 4 Overall Difficulty ⭐⭐⭐

~ Tanvi Deshmukh

⏱️23 August 2026

Searching Algorithms: The Complete Beginner to Advanced Guide

You do this dozens of times a day without thinking about it. You type a name into your phone's contact list. You hit Ctrl+F on a long page to jump to one word. You ask Google Maps for the fastest way home. Every one of those is a searching problem and every one of them is solved by an algorithm that someone had to actually design, because "just look through everything" stops being good enough the moment the amount of data gets large. That's the whole story of searching algorithms, real

~ Jack Wilson

⏱️23 August 2026

System Design Basics: High Level Design (HLD) vs Low Level Design (LLD)

Let me tell you about a project where skipping this distinction cost us real time, not a hypothetical one. A team I was part of needed to build an automated campaign service, something that would listen for events (like "a customer joined a segment") and trigger a chain of downstream actions across several other services. Everyone was excited and everyone wanted to start coding fast. We split into two groups. One group started writing the event schema and the database tables f

~ Rashmi Khatri

⏱️22 August 2026

Functional vs Non-Functional Requirements (With Real Examples)

I want to start with something that actually happened, not a textbook definition, because that's how this topic actually clicked for me. A few years ago, I was part of a small team building an internal service that sent out automated notifications think order confirmations, delivery updates, that kind of thing. The product manager gave us a clean, well-written list of features, send an email when an order is placed, send an SMS when it ships, let users choose which notificati

~ Mayank Saxena

⏱️22 August 2026

Binary Search Explained: A Beginner's Guide With Real Examples

Think about the last time you looked up a word in a physical dictionary. You didn't start from page 1 and flip through every single page until you found your word. You opened it somewhere in the middle, saw you landed on words starting with "M," and if your word started with "R," you flipped forward straight into the second half, completely ignoring the first half. Then you did it again and again, narrowing down faster and faster, until you landed on the exact page. You already knew

~ CodeWarlord

⏱️22 August 2026

DFS vs BFS: Graph Traversal Explained with Examples

Let me start with something that has nothing to do with code. Imagine you're at a family gathering and you're trying to figure out how you're related to some distant cousin you just met. You could do this in two very different ways. You could pick one side of the family and go as deep as possible your dad, his dad, his dad's brother, that brother's son following one branch all the way down before checking any other branch. Or you could go layer by layer first check all your direct sibli

~ CodeWarlord

⏱️17 August 2026

Availability in System Design: A Beginner-to-Advanced Guide

Think about the last time you tried to book a train ticket the moment tickets opened or grab concert tickets the second they went live and the site just... didn't load. Or gave you a spinning wheel forever. Or showed "Something went wrong, please try again." That's not a bug someone forgot to fix. That's availability or rather, the lack of it showing up in the one place everyone actually notices: right in front of them, at the worst possible moment. Availability is one of those sys

~ Chetan Vashisht

⏱️16 August 2026

My Microsoft SDE-2 Interview Experience (2026) : Paused, Closed and Then Reopened Two Months Later

This one didn't go in a straight line and I think that's exactly why it's worth writing down. I interviewed for an SDE-2 role on the Windows team as part of a hiring drive. Three rounds in, everything just... stopped. Not rejected. Not moving forward. Paused. Then the role got closed entirely. Then, almost two months later, a completely different team reached out because they'd read my old feedback and wanted to pick up where it left off. I want to walk through all five rounds, inc

~ Sameer Kulkarni

⏱️15 August 2026

Backtracking for Beginners: The Complete Guide from Basics to Advanced Patterns

The first time I saw a backtracking problem in an interview, I remember writing a solution that technically worked, but it took me nearly the whole 45 minutes and I couldn't explain why it worked. I had basically copied the shape of a solution I'd seen before and hoped the interviewer wouldn't ask me to explain it. He did. I fumbled. Years later, sitting on the other side of the table, I see this exact same thing happen almost every week. Someone writes a backtracking solution that

~ CodeWarlord

⏱️13 August 2026

File Management in Linux: What's Really Going On Under the Hood

Here's a scenario that's confused almost everyone who's spent real time on a Linux box: you delete a huge log file with rm , run df -h expecting the disk to breathe again, and... nothing. Same 98% full. You didn't imagine it and the file isn't hiding somewhere. Something else is going on and understanding it is really the whole point of this article. Most people learn Linux file management backwards. They learn cp , mv , rm , maybe chmod and call it done which is fine, until the day som

~ Himanshu Rawat

⏱️12 August 2026

Linux Commands in DevOps: The Complete Practical Guide

Somewhere around 3 AM, a pager goes off. The deployment that looked fine in staging is now throwing 502s in production. There's no dashboard open, no fancy GUI , just an SSH session into a box, a blinking cursor and whatever Linux commands you actually remember under pressure. That's the real test of "knowing Linux commands." Not whether you can recite ls -la from memory, but whether you can find the process eating all the memory, tail the right log file and roll back a bad deploy b

~ Deepali Saxena

⏱️12 August 2026

CAP Theorem in System Design: Consistency, Availability and Partition Tolerance Explained

Imagine a database cluster running across two data centers :- one in Mumbai and another in Singapore. Data is replicated between them so that either location can continue serving users if the other goes down. Now imagine the network connection between the two data centers suddenly fails. The servers in Mumbai are healthy. The servers in Singapore are healthy. Applications in both locations are still receiving requests. The only thing that has changed is that the two sides c

~ Neel Mishra

⏱️12 August 2026

My Oracle Interview Experience (July 2026) : Round 1 (Senior Platform Engineer)

I'll be honest, I went into this round expecting mostly systems and infra questions, given the "Platform Engineer" title. Instead I got one array problem that looked deceptively simple and one SQL question that looked deceptively simple in a completely different way. Both of them had a trap sitting just under the surface and I walked into both traps before I found my way out. This is the write-up of Round 1 exactly as it happened, mistakes included. I'll add the later rounds as s

~ Nishant Verma

⏱️12 August 2026

Dynamic Programming for Beginners: Thinking in Subproblems

I remember the exact moment DP stopped scaring me. I was solving the coin change problem for maybe the fifth time, still not really understanding it, when my mentor at the time asked me one simple question: "Forget the code. If I gave you the answer for a smaller amount, could you use it to build the answer for a bigger amount?" That's it. That one question is the entire idea behind Dynamic Programming. Everything else the tables, the recursion, the dpi arrays is just bookkee

~ CodeWarlord

⏱️11 August 2026

My Microsoft SWE Interview Experience (July 2026): 4 Rounds, Real Mistakes and the Offer

I got the loop invite on a Tuesday and spent the next week and a half in that specific state every engineer knows well half preparing, half pretending you're not nervous about it. Four rounds, roughly 45 minutes each, back to back over two days. Coding, low-level design, high-level design and a managerial round to close it out. I'm writing this the way it actually happened, not the polished version. I got things wrong in every single round except the last one. The interviewers di

~ Lana Rose

⏱️11 August 2026

Harness Engineering Explained: What It Is, Why It Matters and How It Works (With Real Examples)

If you have followed AI news in 2026, you have probably seen a new term everywhere harness engineering . It is being called the next big skill after prompt engineering and context engineering. Big companies like OpenAI and AWS are building products around it. Engineers on LinkedIn and X are debating it every week. But most articles on this topic use heavy language and skip the basics. This article explains harness engineering in plain words, shows the real problem it solves, w

~ Rahul Singh

⏱️10 August 2026

My Teradata SWE Intern Interview Experience (Full Story, Real Code, Real Mistakes)

I want to share my Teradata SWE Intern interview experience in a simple and honest way. I made mistakes. The interviewer gave me hints. I fixed my answers live. This is exactly how it happened, round by round, with the real Java code I wrote. If you are preparing for a Teradata SWE intern interview or any Java + DSA interview, this post will help you know what to expect. Detail Info Company Teradata Role Software Engineer Intern (SWE Intern) Number of rounds 2 (both technical) Roun

~ Janhavi Rajput

⏱️10 August 2026

My Adobe Interview Experience for Android MTS-2 (SDE-III Level) ~ Full Breakdown

If you are prepping for an Android interview at Adobe, this one is for you. I recently gave the interview for the MTS-2 Android role and I want to share what happened, round by round, in plain simple words. Quick intro: I have 2 years of experience and I currently work as an Android Engineer at a startup, at the SDE-III level. Result is still pending as I write this. There were 4 rounds: Android Basics Deep Dive DSA Round System Design Hiring Manager Round Let's get into it. Round 1: An

~ Ekta chaudhary

⏱️09 August 2026

How to Approach Any DSA Interview Problem : A Complete Step-by-Step Guide

I have sat on the other side of the table for more than 2,000 coding interviews. Not two hundred. Two thousand. And here is the thing that still surprises new interviewers when I tell them: most people who fail these interviews know the algorithm. They just don't know how to use it in a room with someone watching them think. I have watched a candidate who had 500+ LeetCode problems solved freeze on an easy array question because the interviewer asked one follow-up he wasn't expect

~ Jon Chu

⏱️07 August 2026

I Got Rejected by Google After 5 Rounds : Here's Everything I Learned (L4 Backend Engineer)

I still remember opening the rejection email. Three and a half weeks of prep, five rounds and one line that said "we've decided not to move forward at this time." No specifics, no feedback, just silence wrapped in polite corporate language. If you're reading this because you have a Google interview coming up, I want this to feel different from the usual "here are the questions I was asked" post. I want to walk you through how I actually thought through each problem brute force, th

~ Gagan Bansal

⏱️06 August 2026